Biology 1AL - Lecture 7: Lab 7: Anatomy

>>INSTRUCTOR: Let's get started. Complete shifting gears. Complete shift in
gear. So a lot of people said the first part was very hard, very conceptual, etc., etc.,
I know the lab exam was hard. Very challenging you will get them back in lab this week.
And if you don't want to look at it, don't look at it, okay.
Tell the GSI I'll get it from you next week, the reason being is if you think you're going
to be so disheartened depressed, that it's going to do you irrevocable damage, on lecture
exam 2, which are the e mails I usually get, don't then look at it. You can hold off, but
the bottom line is we're going to move on. Soﾊ
>>STUDENT: [Indiscernible] >>INSTRUCTOR: The average was I believe around
60.7 or so. Percent. The exam was worth 100, so of 0.7
is the same as percentage. What was the A? I don't remember the cut off, but I think
I printed it out you will get a detailed answer key, which I will type up after the GSI meeting
tonight. So either you'll get a sheet that you'll print
out just the like lecture exam is, and it will show for each grade. The class has been
curved it has always been curve and you will see that reflected in the scores, for example,
the A range, goes down to 71 points. Okay.
Anyway, you'll see this, you'll get this, okay.
All right. So, let's move on.
As I mentioned the second part, should we just chitchat for a little bit?
I'm more than game. Okay, so the bottom line is first part is conceptual, the second part
is a lot of memorization I've been getting e mails from students who are concerned about
oh there's so much material there's no way I can learn all of this, etc., you actually
know a fair amount of it in especially the rat can your own anatomy, there are a few
differences, we'll point them out. When you think about humans and they're wonderful physiology
and anatomy, various heartbeats and how the heart works and all of that, I would like
you to realize for every organism you can say the same thing.
Whether it's a bacterium you wouldn't necessarily be talking about organ systems but you would
be talking about gene expressions. Whether you're talking about a fungus growing, etc.,
so I know sometimes you got bogged down on tall of the details, and it's hard to see
the beauty of it, but keep track of all of the intricacies and the amazements there that's
there. The rats within the chordata that's the phylum,
deuterostome, I'll talk about protostome and deuterostome. And organ systems you've heard
about the kidney excretory system you will get a lot of this in the 1A lecture, so I
won't spend a lot of long time on various things like what's the liver doing, etc.,
because you will get that repeatedly in the 1A class, realize that realistically, for
biology, oops why did it notﾊ keep in mind that biology just to learn a bunch of facts
doesn't make sense unless you look at evolution there's a student asked a question couple
of days about are want to gene duplication with the current population size of that,
how this ever become represented in the population so it becomes integrated into that species?
It doesn't take much of a percentage over thousands or ten of thousands of generations
to be selected for, and certain mutations might have a average rate of 5 to 10%, that's
huge. So for 10,000 generations you see how it easily be incorporated that species. So
that's how evolution is working. Realize that evolution may be considered to be very cruel
there's a mutation, if it's selected for, it doesn't survive it's no longer in the population,
no longer in species, those genes, those traits so key thing is, with evolution we're donating
genes. Grades I had some of you are officeﾊ maybe on Wednesday, student talked to me about
grades how they don't think they're fair, how adjustments aren't fair, so let me go
over again how I did this adjustments here, because I know that some GSIs grade much more
harshly than others and if you're in that section you may think it's unfair so if I
didn't do some sort of adjustment in the end, if you're in section, you would get penalized
because as you know at the end I take a make a distribution, and I they is where the A+
is, the A, the A ﾊand that's the range. Well, what we do is that's your total scores
so you're total score also be based upon lab exam 1, it will be based upon your quiz scores.
And we'll drop the lowest of the quiz scores. So I think that 11 quizzes or 10, I can't
remember how many we have this semester but we'll drop the lowest and then you'll have
lab exam 2. And then I'll tell you the format for lab
exam 2 this semester verses what we've done in the past. All students will take the lab
exam 1, you did this, all students this semester, which is unique to this semester, will take
the same lab exam 2, so I'll tell you how that will work, but I have to adjust for quiz
scores so the way I'm going do this, I went over the first lecture, I can will do it again.
I do it like this, when I take the plot lab exam 1, okay.
And then I do, quiz scores here. And you'll see that some sections of course
areﾊ yeah, they have low quiz scores but other sections have done well on lab exam
1 but they're way down here on this graph, so what I will do is do a linear reaction,
I will move the slope up the easiest of the 26 lab sections. So indeed the slope is maintained,
I just move it up to the easiest. What I've done is given the GSI guidelines
as we go through the semester, and say, you know, shoot for a an average of this, etc.,
etc., now that we have the lab exam 1 scores we know which sections have done a little
bit better than others, and this is reproducible from semester to semester I looked atﾊ I
haven't done it this semester, but I've done it in past semester will I will take the students
in lab section 1, well, let's say 1, 3, we have different numbering system this semester,
so I haven't done 1, 1, 3, but in the past I did sections that were equivalent to 1,
1, 3 and say, 1, 17 and equivalent to 3, 2, 5 etc. and I would look to see what they're
scores were in 1A, these 28 students would have completely discussion GSIs, then I would
call how did this student do in lecture 1 A exam with completely discussion GSIs and
there would be a remarkable trend between how they did in this group, verses this last
class so it's a relevant thing to be doing. So that having been said, I'm going to put
up the next graph which youﾊdo not have because I just got the data and it will show
you the rank in the sections, let me tell you what this means. Because, I hate, I detest,
can't tell you how much I hate giving grades. The reason why is because most people aren't
happy with they're grades. I can't do a whole lot about that, okay.
Except help you work towards the grades you want, which is why I had so many office hours
lab exam 1, same with lab exam 2, I will hold office hours to help you, if this section
did really well on lab exam 1, even if they're there, once they do this graph and move it
up to the easiest they will get a large adjustment. If this section down here, has done poorly,
then again it will be moved to the graph, but they're adjustment will not be as large
as this adjustment because this position is further to the right.
This is lab exam 1, and this semester, once lab exam 2 is given, I will also use that
as a data point because it's the same exam. Okay, so having been said let's look at the
data, we'll warn you right now, what usually happens the students that are in the sections
here, think it's really unfair that I'm adding points to this section they got more.
But realize this is the fair way to do it, it's not fair to give everyone the same average
because they indeed don't earn the same average in 1A and they indeed don't earn the same
average on the standardized exams. So, I've spent many hours thinking about this, I've
spent time with statisticians, this is the best way that I know of to do this, I've been
told to just ignore quizzes tell you guys they're going to count and thenﾊ oops I
sorry I didn't meanﾊ I would never do that. That would just be wrong, okay. So the bottom
line is, here's the next graph, I'll give with you a couple of minutes to look at this
in terms of the rankings. Highest scores to lowest.
I know everyone's quickly looking to see where they're at.
Okay. We move on.
Okay here's why which move on, because I would use this system, I think it's a fairest way
to do it, it really does account for the differences in quizzes, okay. In the end, in the end,
when students are borderline, so if a student's right here, and they're borderline from the
Aﾊ ﾊto A I meet with the GSIs individually. Meet with them individually and go over section
by section, those two students who are close to the borderline, by this I don't mean 10
points I mean one or 2 points and I say did they help other students how did they do in
pre labs and worksheets, how did they do on these things so we have an individual discussion
about each student who is borderline so that's the best I can do to make it as fair as possible.
I think it should be done, I've talked to ombudsperson repeatedly they have told me
they like the system, they wish more professors with will do it. I will spend 15 minutes doing
this adjustment. I take a lot of heat doing the adjustment but it's the fair thing to
do, because it rewards the students here. It does not penalize these students. It only
penalizes these students relative to the system that is unfair.
Inherently unfair. So, not much as to be gained by discussing it more we can talk about it
individually if you want. I no ideal system I would like to tell you that grades are not
the most important thing. Okay.
They're not the best predictor of your future. But unfortunately, for many things, that's
what they use. It is not my call, okay.
But anyway, no one grade in one class will necessarily impact you unless it's with one
of the things where you must have this sort of grade, but a C, C +, that's not going to
ruin your life. Nowhere in Aﾊ ﾊor a A because you wanted
the A +, there's a question here. >>STUDENT: [Indiscernible]
>>INSTRUCTOR: So, will theﾊ the data I just be put up be on bSpace, I can put it up there
if you like. So let's move on. Yes?
>>STUDENT: [Indiscernible] >>INSTRUCTOR: Uh huh.
>>STUDENT: [Indiscernible] >>INSTRUCTOR: They're notﾊ so the comment
is, in the low sections where crippled, no. No what I hear this sort of thing I hear students
saying, my fellow students are losers, comment from them, I'm not saying that.
But I hear these sorts of comments from students it's not case you're not crippled, within
this section, students can still get A+s, in fact, the student with the highest grade
was in the section that had the lowest adjustment. They did that well in lab exam 1, lab exam
2. >>STUDENT: [Indiscernible]
>>INSTRUCTOR: It's not harder, what happens is, it is indeed true that your adjustment
will not be as high, wouldn't you say that's inherently fair? Because you're section did
not do as well this section. >>STUDENT: [Indiscernible]
>>INSTRUCTOR: Because within a section, you are taking the same quiz, and consequently
within the section I do the adjustments the same for that. With respect to the lab exam
1 and lab exam 2 I'm notﾊI don't go just those because you took the same one as all
of the other students, so you can still do really well in your section. But it is true,
if you're quiz averages are, you know, if your section is not doing as well here, then
indeed you're section will not get as good. But it's not necessary that your crippled
it's not that it's not fair. Now that having been said this, is what I hear and this is
going to be the end of the discussion, because I go through this, I hear from these students
all the time about how unfair this is. But you know, think if I didn't do it.
How unfair it would be to these students. Wouldn't you agree it would be unfair to these
students if I didn't do the adjustment? What would you want in this section, that just
rocked on the exam but your section average was so low would you think that's fair? They're
crippled they have a huge disadvantage baa we can talk about this later. But the bottom
line is no one, no one system is perfect. Every system is inherently flawed unless you
all took the exact same quiz at the exact same time every week.
That would be only way around it, which would be Monday night I could have at a quiz at
the start of lecture. Would you guys think that would be a good system? Some people say,
yes, some people say no. I use not have quizzes so I didn't use to have quizzes. The semester
I started quizzes, my GSIs who taught pre quiz and post quiz said my god it's a night
and day difference the students come prepared. When we did have quizzes, they wouldn't come
prepared because they would cop pre pre labs and worksheets, so it's helps in learning
aspect and coming prepare so I think it helps in that regard. I don't know of a more fair
system, I know that students within these sections always think itﾕs not fair. But
let's move on. Okay. And that is why I don't like talking about grades, last question.
>>STUDENT: [Indiscernible] >>INSTRUCTOR: I will post this on bSpace.
So, later it will be posted on bSpace and you can take 10 minutes to look at it. All
right. If you really want it now, right?
There. >>STUDENT: [Indiscernible]
>>INSTRUCTOR: Onlyﾊ this is the average that's the rank. 1 through 26 we have 26 lab
sections this is the lab number. So yes, only quizzes are adjusted because
all students take lab exam 1, so I don't think I should be adjusted lab exam 1. Lab exam
2 this semester all students will take the same. This is only about grades it has nothing
to do with learning. Time line, so, keep in mind the timeframes
we're talking here. We're not talking 10,000 years, if you think back it hasn't been that
many generations from the Roman Empire. Not many generations at all.
Not many generations took caveman. So realistically when we go back like we're thinking long timeframes
and it's hard for us to wrap our head around that, 4.6ﾊbillion years ago the earth formed.
So, there's been a long time for things to happen.
The most file low that we'll be by studding is 500ﾊmillion years ago. We use to have
a separate lab on vertebrates where we would look at them, we don't have that lab anymore.
We don't have as many lab exercises, with respect to classification, I had a question
on the lab about cladistics, knowing how the tree shows relationships and the closer the
branches are, the closer the relationships are.
This is showing a subsetting this is where the species it falls within a genus. We're
talking more and larger numbers of species or taxa.
They're multicellular, they're eukaryotic, they tend not to have cell walls and they're have
collagen as a protein. So if you find collagen it's unique to the group animals.
And I don't mean to disgrace, because I know grades are important, but I know sometimes
we don't ever come to an agreement on that. So, here just shows you this in terms of the
groups, so we looking at a lot of these various groups in lab, for example we will look and mollusk, annelids, arthropods. And cnidarias
so we'll look at a smattering of these we don't have time to look at all of these, and
we've chosen a few species for a various reasons we'll study, they're easy to obtain, we can
get fresh specimens of them and they show general aspects of the group.
This is not in your book unfortunately you have a kind of a similar diagram but not quite
the same. What shows here is just, showing the relationships that the [Indiscernible]
and the thing about cladistics I love, but the thing about cladistics I hate is, that
branch diagram really shows you the relationship and they should be evolutionary relationships
and sometimes we don't know how to draw them. But I do want to point out a couple of things
which is confusing for students, this will become more apparent when we do the arthropods
because we'll look at more subsets withinﾊhere, but when we have this sort of thing, we can
talk about the end points whether this is a genus level or species level, but within
here that's a collate as well, so I can remember this 5. This is a clade here. This is a clade
here. So reality is if we had a million species
here, we'd have a million branch points so in fact we would have way more taxa or clades,
because these two introduce a clade. These two introduce another clade, so in fact we
end up with, maybe 10ﾊmillions or 100ﾊmillion different clades now we never discuss but
that's the one drawback to clades so we tend to do these branch at large levels. So if
you study a particular family and you will do that and subdivide it and subdivide. So
section 1, in terms of the protocells, they're divided in three I groups.
We'll be looking at, I'll show an average of this. It refers to specialized feeding
dependence they have during development. And level development. And these things shed they're
outer skin they have molting so we'll see that with the arthropods, within the deuterostomes,
scar dish in a couple of weeks and the claw dates this week in terms of the rat. And this
shows you the [Indiscernible] the specific ones we'll look at. And then, here, in terms
of ecdysones, nematode are interesting you had an introduction to these in the 1A class.
There's an example of nematodes, during office hours today studentﾊ we'll do that with
lab. I'll introduce this, is another way of showing you this. Realize that at these branch
points there are names but what's useful for us potentially what has risen in terms of
evolution, so we have true fibers at this branch point. Three germ layers and we'll
talk about the three germ layers. And here's another example.
The lophotrochozoan, and you see this forms. Realize that we typically are looking at the
dealt organisms and not often at the larva forms. But we will occasionally look at the
larva forms. Larva means they're not able to make viable gametes. When they reach puberty
and they make gametes, biologically we say they're adults.
May not be allowed to vote but they take viable gametes.
All right in terms of this is this is our page 155 in the lab manual. Students complain
about this part to memorize in the part of the course. I think this clade here is very
useful it shows you, you know, some aspects by [Indiscernible] it shows that within this
clade we have two branches and within here, for our purposes we'll have two clades, we
yield [Indiscernible] and there's various features there. This a great way to organize
the material. In terms of trying to rememberﾊ I'll show you some charts. If you fill those
charts out for yourself, if you take the time, you'll learn a lot better. It forces you to
go through the lab manual, read it again and fill out the charts, okay.
This tree here is also very useful because it gives you images of things.
And that's going to be helpful because the lab exam will be a lot of images. We'll talk
about hierarchy, we've talked about before, in this case, we'll talk about cells going
into tissues, there's various tissue types. There's 4 primary tissue types.
Mr.ﾊWeisblat will talk about this on Monday. The four primary tissue types.
And within here we have different subtypes, within muscular, we have cardiac for the heart,
we can skeletal, and smooth muscle. Okay.
So, terminology, axis verses plane, I just think of this way, within this laser, I'm
expected to make an axis, because it's line so, right now, this laser would be going,
it would be going from ventral to dorsal, so an axis is just a line of direction. If
I have a plane it's two axes. And sometimes people have difficulty understanding
what the two axes are. If this is a plane and you're trying to figure out the axes it
consist take your hand and go around the perimeter of the paper, so this would be axis? Transverse
and this would be what axis? Dorsal ventral. What axis would this be?
Dorsal ventral and superior inferior or potentially anterior, posterior.
Okay. So be familiar with those planes, often time
in the lab exams in the past we would have an organism and if have a plane and ask you
to identify this plane and in terms of humans, this illustrates here, so there's that midsagittal
plane that's right in the middle. The frontal plane is here, so it would be
transverse and superior, inferior. Transverse plane is across a section is here.
Includes dorsal ventricle and transverse, so be familiar with those, terminology that
people have familiar with. So let's first talk about a see loam. We're effectively a
tube within a tube, so woe took a chain saw to myself, we would get the outside body wall.
And then we goat my GI tract, so this is the tube, and this the outer tube. And the case
of humans and that we are what's called coelomate which means we have a cavity between those
two tubes and in the case ofﾊus we're true see low mates, so it's epithelial derived
from mesoderm we have a lining like this and this comes down and surrounds the GI tract.
The average of being a true coelomate, it gives you a cavity, it your heart is in a
cavity, it's called the pericardia cavity, that cavity allows your heart to expand, as
it fills up with blood and when you contract it shrinks within that if you have a solid
pack it would be hard to do. It would be embarrassing if didn't have a [Indiscernible] cavity, you
compress that bladder and have urine squirt out, very embarrassing that's a minor thing.
The other thing is if you think about this, we have this GI tract, go from mouth to anus,
we can have the stomach muscular conﾊtraction and it can [Indiscernible] so a see loam is
like this it means there's a cavity between this tube, the GI tube, where there's a [Indiscernible]
cavity, or whether its the GI tract and we'll talk more about that, but if there's a cavity
here, it's a coelom it is a true coelomate this is lined with peritoneum, or with the
mesoderm with the development. This GI tract can be suspended it's not flopping around.
So you can have blood vessels, lead to this, to take [Indiscernible] of the GI tract, distribute
it to your liver so your liver can process it you can have blood going to this, to nourish
the GI tract things like that. Okay.
So coelom is illustrated in the next slide here, just kind of color coding it with a
solid packing between theﾊ in this case a [Indiscernible] cavity because there's one
opening it does not have a mouth and a separate anus it has just one structure we call the
mouth anus so that he is a gastric [Indiscernible] cavity there's no coelom. In a true coelomate
there's a cavity between the outside wall and it's lined with mesoderm, and the coelomate
but it doesn't around the GI tract. Okay. So let's go over a few times.
[Indiscernible] cavity, so there's no way to get specialization along the GI track.
We have two openings and mouth and anus so we can specialization along the track, so
certain parts will be specialized for storage, or fragmentation or absorption.
The other cool aspect of that is that, by doing this, you can eat nonstop.
If you think about it, it's kind of good per certain organisms or the advantage is you
can take large of amounts of food socially and then escape predation, you're susceptible
to predation when mete feeding, you've probably seen this before, [Indiscernible] fill up
they're cheeks and runoff to a tree so they're protected so there's behavior modification.
And metamerism, we've seen that repeated many times.
Closed verses open circulatory system. I'll use the term blood for that fluid within
the vessels is always contained within the vessels, open means there is actually a break
in those vessels you still have a pump, it's just means that when we do have a pump, and
there's vessels that lead away they often have to call those arteries but there's fluid
there's a break there, so if you have a cell here, that fluid immediately surrounds those
cells. So, this is called: An open circulatory system.
And the fluid is called: Hemolymph. HEMO like blood, lymph like the lymph system.
The blood is contained within the vessels all the time.
Now, we can create a open circulatory system in yourself and I do this demo every semester,
this time not as dramatic. Might take a hammer to my hand.
Just kidding it's always an accident happens this time of year. But you can see that underneath
my fingernail there, basically bruising. I've converted capillaries that were closed to
open system, and I spilled the blood out to my interstitial space, so in that case, I
know I would have all of my Bachelor's degree within the vessel, it's now immediately surrounding
the cells. The average in a system that has it open, less distance to diffuse the disadvantage
loss in pressure, every system has advantages and disadvantages.
But the close system the advantage we can maintain pressures, the disadvantage with
a closed system if this fluids always within a vessel, if I want to exchange to this cell
I have to cross the membrane of that vessel, I then get to that cell.
So the distance is going to be greater and I have another membrane to cross.
So that's the disadvantage. So, everybody has advantages and disadvantages
few terms we'll go over right now. Hyper verses hypo.
There's always a reference there. HyperﾊA means is hyper to B, means something
more than relative to B, if A is hyper to B, let's say hypertonic, if I want to use
that term. In terms of tonicity, in terms of solutes, I can also say B is hypotonic
to A. of they mean the exact same thing, you always have to have the reference.
Okay. So, A is hypertonic to B, B is hypotonic to
A so there's always a reference there. When you're using that sort of terminology.
Systems, integument tear nervous, endocrine, skeletal, muscular, immune. Illustrate this
tube within a tube, we sometimes have in pocketing or invaginations, like leading to the lungs
for gas exchange. So increase surface area. Reproductive gametes going outside.
This just in shows you GI track, mouth, leading to the anus, here this distal part is called
the cloaca because gametes from the gonads excretory [Indiscernible] from the kidney
feces all merge in the cloaca and the anus, in terms of the systems I know all of you
have seen them before, I'm not going to read through the list, I would like you to just
take a minute or two to think about some of the requirements you've learned or think about
that a cell must do, the requirements that a cell must meet and then extrapolate it into
the organism that is multicellular. So think about what cells might need and then I'll
have a few some of you come up and put a few thing tons board. Question do this all night
long. So to make this go quick. What I'm going to do is just ask the students far right here,
to come up on this board, and put a cell requirement and the first one up is the easiest job, because
nothing else is on the board. So come on it. That's the incentive to come up quickly, right.
You need chalk? Here.
ATP cell, there has to be some mechanism to activate the ATP, we have to have feeding
behavior, we have to have GI tract. We have to have a way to distribute the nutrients.
Water so we have to have a way to ingest the water whether it's through feeding or drink
mechanisms we have to have ways to maintain the tonicity, the proper osmotic balance.
Waste; whether those are nitrogenous waste, or nucleic acids because of the nitrogen or
whether we're talking about feces, okay, so we need oxygen for cellular respiration, and
we have to have a system distributed to distribute it appropriately. Nutrients acquired through
the diet. That's notﾊ let me put the one that's really
important. Reproductions.
How could you guys forget that one? Right.
Distributing the gametes. Distribute the gametes making offspring getting those genes into
the subsequent generations right. You are a effectively a biological failure if your
genes don't get into the next generation, unless you some howﾊ I don't want you to
think about this too much, unless you help your brother or sister to have more kids because
they're related to you, right. So there'sﾊ I don't know if any of you ever
had partners who say, if there is a burning fire would you grab me or your mom or dad?
Anybody have that? I always say, I would grab my mom or dad because
they have the same genes you don't. It doesn't win me points. No, I actuallyﾊ
I don't answer the question. All right. Anyway.
So, what I did here was try to show you the things that a cell needs you know we could
have done any level, we can talk about DNA synthesize, various levels like that, there
was immune here, no one brought up immune, defense, there's all sorts ofﾊthings that
we can be here, we have to have ways to separate inside from outside. So the things that a
cell has to contend with, but at the multicellular level, if it's a multicellular organism. So
they have the systems to do it. In terms of chordata. So what this means in the cladogram.
In lab exam 2, or in lab exam 1 was saw if there's unique features it will pin it to
the point of the can I not gram. Things like multicellular does not pin it
to particular clade it's not unique it's shared through out many other organisms so the 4
unique features. And this is sometimes during development or
in the [Indiscernible]. Sometimes during development or in the adult
this, is idealized diagram will have some slides in lab you can see this more clearly
it's stained here's the anus, here's the tail here so that's post anal tail here's pharyngeal
slits here. We'll talk about this more during the lab.
And dorsal to that is the dorsal hallow nerve cord. The spinal cord is hallow what fluid
is it filled in? Cerebral spinal fluid, leads to the brain, it's also hallow, what the do
you think is a good name? Ventricles. So if you're fun facts here.
Number cells in the human body. Anyone know?
But 200ﾊtrillion. Okay. Number of cell types in the human body about
200 cell types. In terms of number of [Indiscernible] I need
to explain what I mean by this. Inside verses outside. To be inside you're
body, you have to cross a cell membrane. So, when I took that drink I took liquid into
my oral cavity and then went to my stomach it has not crossed a cell membrane yet so
that effectively outside of my body, I can stick that, I could stick my finger down my
throat and regurgitate. Won't do it. Likewise if I took dental floss, tied it to my tooth.
Swallowed it and 3 days, do not visualize, I have the other end, right?
And you can floss. You'd feel it tight in the tooth. Now, what I have to say is please
do not come to me and say, would you give me extra credit points if I do it.
Do not do it it's dangerous. How many [Indiscernible] anybody want to be
a vet? Okay, so veterinarian haves to do with this a lot. People take they're dental floss
they put it in the trashcan the cat or dog gets into it they swallow it and the dental
floss it's sharp. If you're a baker, you want niceﾊcookie doe, pull.
The other thing you can use is piano wire it's stronger so if you're to do there's a
likely chance you would cut your GI tract. So no extra credit.
Okay. ﾊSo don't do it. But it is outside your
body and the reason it's important because everybody always says you have, all of these
200ﾊ I think it's aﾊ you have 20ﾊquadrillion bacterial cells and they always say its inside
of your body, they're not inside your body. They're typically on the surface of your body,
if they're inside of your body your immune system is attacking them that's why you have
the immune system. Okay. You certainly have lots of bacteria in your
body, you're fighting infections all the time, you lots of worms in you, etc., etc., your
immune system a always dealing with the stuff. Link the blood vessels the key thing here
is when we talk about exchange and I have haven't worked with Dr.ﾊWeisblat before
so hopefully he'll spend time on this, we'll talk about diffusions and we'll talk about
how the rate is proportional of some constraint which you can't change for that compound x
a surface area, over the distance it has to diffuse, so sometimes you to have high rates
or gas exchange so we'll have large surface area for the exchange so when they there's
100,000ﾊmiles of blood vessels they don't mean there's 100,000 of arteries, the length
of the arteries would be rather limited but they subdivide and subdivide into capillaries,
and so that's where we get that huge distance. And in terms of the surface area, in this
case just a distance of the blood vessels, but we're having a large amount of surface
area for exchange of nutrients and gases a and the distance gets smaller and smaller
so we increase that rate. So, there's about 100 thou miles there.
Surface of the lungs 300ﾊmeters squared. Now what is the total length of the DNA in
the human body this is not compacted as Dr.ﾊFischer if he mentioned it's about 2 [Indiscernible].
Then I realize that always they do these sorts of things, is the distance as circumference
of the earth, how many of you paddle around the earth? Not many. So the moon and back?
100 times is the answer. But I don't think I o anybody been to the moon and back, how
many times would it be from here to here and VLC and back? And it's 400ﾊmillion trips
from here to [Indiscernible]. That's the length of DNA. Anyway it's huge.
Excretory system, you're familiar with this. Elimination is coming from your diet. Nitrogenous
waste from the amino acids, from the proteins and to a lesser expends nucleic acids usually
there's more proteins than nucleic nucleic acids. Not only does this deal as many put
up here the water balance, water balance is one aspect of this, but within here is the
balance of specific ions too. Calcium, potassium, you know, phosphorous,
those sorts of things so you have to balance each of those.
The difference between osmoconformer verses osmoregulator is in the next slide. And then
this, people always ask how I can study for you, we have your make drawings the drawings
are for our purposes the better your drawing is the better it is for your study guide.
Checklist each lab there's a checklist you go and say yes I saw this I can visualize
it if you can visualize it and say I know where the cladengram is, I know what it looks
like you should do well on the exam. So there's checklist to help you in the lab.
Osmoconformers match the external environment. They do not extend energy to maintain they're
tonicity. So, I'll say that again, because it's a little
twisted they don't extend energy to maintain they're toe necessity they match they're environment.
That doesn't mean they have the same ion concentration, all of tonicity is the same, matching the
environment but that doesn't mean they have the same levels of sodium as the external
environment or the same levels of potassium. They specific ions but over all they match
tonicity. For osmoregulators, they have sort of a set
point and Dr.ﾊWeisblat will talk about hemostasis. And for those that are osmoconformers they're
ranges that end up being lethal. Okay.
So in terms of nitrogenous waste. If you're aquatic, typically you get rid of
your nitrogenous waist in the form of pneumonia, it's toxic so you can't have high levels of
it in your body but you can use the external environment to dilute it. So things that are
aquatic they excrete it as ammonia. Yourselves and other organisms we often excrete it adds
urea because it's not toxic so we can have high levels of urea, for example in the kidney
to regulate this, and if it's not toxic. We also have two nitrogenous molecules there
so we're excreting more nitrogen per molecule but it takes steps to get there. So we're
expending energy to form the urea. Uric acid is better yet. But nitrogens but
more steps, 10 steps to get here. The big average of uric acid it will precipitate
out of solution so you haven't to lose much water to do it. Urea you still have to make
it soluble and it is toxic. You still have to use water for that. But with uric acid
you don't have to. Bird droppings when you see white you're seeing the uric acid it's
crystal and come outs of solution. In terms of some things we'll be looking at, the flat
worms we'll talk about the gastrovascular cavity and just like the GI tract when something's
in the GI tract it's outside of your body we're absorb nutrients, so what happens this
is a solid packing of cells there's no cavity here, but there's fluid between cells, so
everyone though we say its a solid packing and the indeed the cells are packed in there
tightly but they're there's still interstitial fluid, so what happens interstitial fluid
gets pulled into this tube here, and once it's in this tube, it's effectively outside
of the body well see this over and over again, once it's outside of the body we have it pass
along this tube and we can modify that contents. We can take things [Indiscernible] up like
sugars or amino acids, etc., with that's in that interstitial fluid or we can excrete
things into it, basically to get rid of it. It is exact seining sail thing as for your
excretory system it won't be [Indiscernible] it will be a nephron and you'll see the same
mechanism. This just illustrates this is from Campbell, so this opening this leads to the
outside body wall to that interstitial fluid gets pulled in here. It eats effectively outside
of to body you take things up and you can actively secrete into it but the things you
don't pick up will go outside and be excreted. In terms of [Indiscernible] there's menﾊ
where they have on opening in the coelom, so it is the coelomic fluid in here. Once
it's in the metanephridium things are actively taken up or excreted into it. And since things
being being taken up. We have capillaries beds toﾊ
In terms of the cockroach that we'll be dissecting later. In this case, coelomic fluid is pulled
in, and it actually gets excreted into the GI tract it will be released with the feces
in terms of the kidney I'm sure you've seen this before. Towards the end of the rat dissection,
take the kidney cut it out, and then do a section through it so that you can see the
cortex out here, and the medulla here, and they will look different at the gross level,
you don't need to microscope, you see there's a difference between the cortex and the medulla
and that's because of the microscopic structure we have these structures here these nephrons
and that, and close up of this shows you this, Dr.ﾊWeisblat will spend 20 minutes on this,
I'll just mention briefly what we do here is we have arterial, you're probably aware
that we have arteries branches to our arterials and then they go to capillary beds so we have
arterial approach this capillary bed, called glomerulus, but not all of it goes to the
capillary bed some is released into the arterial right here, so a subset goes through here
and it gets pushed under high pressure in the capillary bed and out and then into this
tube, this caps lair here called Bowman's capsule so that food is being forced into
the tube and once it's in the tube, we selectively take things up or secrete things into it and
then we process it and the waste will go be collected by the kidneys and out through the
urethra. There's lots of ways to tend time op YouTube
checking various things there's interesting, some things in cystoscopy, if you have time
look at it. Probably not before Friday. I know you're busy so I wanted to remind you
again there's a question/answer review, 7 to 9, and 100 GPB. Reproductive system. Function,
producing gametes but also housing those gametes, supporting the gametes, hormone bro duction,
whether it's for secondary characteristics or maintains gamete, for the rat again there
will be various things there. I do want to point out oval duct and fallopian tube are
interchangeable. So in terms of theﾊ here's the kidney here, we will talk about anatomical
position so in humans this is anatomical position that makes this right, this left.
So if you're a surgeon and you know you need to operate on the right arm you know it's
this way, it doesn't matter how the patient is laying this is right anatomically.
So, in this case this is the left kidney. Produces the nitrogenous waste, close to the
[Indiscernible] and out through the urea and the penis. But we have the epididymis here
and here so the testees will be producing the sperm. This will produce the sperm, they're
mature in the epididymis, [Indiscernible] and then out through the urethra.
And the bladder can be hard to find, if it's filled with urine it's easy, it's typically
yellow if it's not, it's this white color, okay. Now this is preserve rats, your rats
will be freshly euthanized please do not name them or play with them. When it comes to lab
exam 2 if you want to, purchase additional rats to do this section over again and that,
I'll give you a list of where you can buy them from, you have them kill them for you
if you want. Please do not take them to bathroom wall and
smack they're head against the wall, I've seen this stuff done it's not treating them
humanely, if you want to kill them on your own and you don't want to have the other group
do I we can kill them for you or you can do dislocation, which breaks the spinal cord,
it'sﾊ instant brain death effectively they feel no brain, etc. it's an approved method.
We'll talk more about that when we get that. In terms of the circulatory system, everyone's
heard of the heart you know that it's distributes bloody fluids, gases, etc., we've discussed
open verses closed diastolic verses diastolic, so systolic is the higher value generated
we can talk about atrial, we can talk about atrial diastole, but when peep talk about
systole and diastole they're talking about the vertical.
So, in they're rat you'll be looking at the rat heart towards the end of the lab, cut
open the rat heart, it is not arrive. When I did this dissection, the rat was arrived
and we actually would drop chemicals on the heart, and see how specific chemicals would
affect the heart rate we had a way to do depth of breathing we had to do a canalization,
they were still alive. We would doﾊ we put a lump of clay on they're chest, we can maybe
they're deep their rates of breathing were, the thing spun like this, your rat though
is dead. That doesn't mean the GI tract will not be
showing peristalsis, you still see it contracting those muscle cellsﾊwill be arrive for hours
but sit brain dead the heart will not be beating I do want to caution you a lot of people take
photographs in sometimes the electrostimulation from a photograph will stimulate the heart
to take a beat or two it has not come back to life. Okay.
No, Iﾊ I point this out to you because some people very [Indiscernible] by this. And it
happens occasionally, so let'sﾊgo over the heart you'll have a [Indiscernible] of this.
In terms of the blood system, heres the arterial capillary here's the venus end. We're having
resistance along this tube, the pressure will decrease, so the higher pressure here forces
fluid out into the interstitial space and that fluid will accumulate.
But what happens is, as that fluid gets forced out it's not cell it's not get forced out
we are effectively increasing the tonicity of the blood, and that pulse fluid back in.
But there is a net loss so we do have fluid always going into this interstitial space
and that's the role of the lymph system to take up that excess fluid, this is an illustration
of elephantiasis, the lymph vessels are plugged here by a worm and so you can't pick up that
excess fluid so you can see how huge body parts can get.
And that just illustrates the key reason for that willing the lymph system. In terms of
the heart, blood flow, let's start here. Anatomical position.
Left side, right side. I hope my rat comes shortly.
Left side, right side. So here's deoxygenated blood coming to the right side, at the upper
chambers, the upper chambers are the atria, the lower chambers, the verticals so when
I do this I'll talk about right side, left side. Anatomical position. Yes?
>>STUDENT: [Indiscernible] >>INSTRUCTOR: Oh, when did it come?
Oh, I never saw it Co. okay I've been involved with lecturing. So yes the rat's here so we'll
get to it. So, right side, left side. So of the right
side, the right atrium is receiving deoxygenated blood goes to the right vertical, and there's
a valve between the atria ventral on both sides and that promotes one way flow and the
AV valve is designed like this, so when it's open it's in this position. So as the fluid
enters the atrium it's free to freely move into the verticals.
Okay. The atria contacts so they have a systolic,
they force the blood into the vertical, and the vertical contacts left and right side,
we'll start with the right side and it contracts toward the apex and that promotes the squeezing
the blood out. Again, increase the [Indiscernible] and happens
is, that increases the pressure within the vertical.
And that causes the AV valve to close like this, it goes backwards like this, that promotes
blood flow not back to the atria, but out to the artery, so arteries lead away from
the heart and this case this artery is going to lead from the right vertical too the lungs
for gags exchange so it's called the pulmonary artery that contains deoxygenated blood and
there's valves there to promote one way flow. But they're designed with the opposite orientation
so the blood is free to move upward and when you don't have that vertical generating that
force in systole it comes to the gravity of that and it will cause the semilunar valves
to close off so that prevents backflow into the verticals so these valves promote one
way flow, this particular AV valve is called the right AV vertical valve or the tricuspid,
this is the pulmonary artery, semilunar valves are sometimes called [Indiscernible] trunk.
Gas exchange occurs we come back to the heart through veins or arteries? Veins these are
pulmonary veins they enter the left atrium, free to the left vertical. Forces residual
blood into the vertical, when it contracts it closes off the AV valve and particular
bicuspid flow, out through the semilunar valve through the aorta. And it gets distributed
to the body since the heart is doing this sort of thing, 60, 1230 times a minute it
does it 24/7, it's highly specialized it doesn't get exhausted but that means, oxygen rich
blood. True this left vertical is filled with oxygen rich blood we have a sheep heart dissected
for you, you can see that the septum is quite think and then you will see that the left
vertical is thicker than the right vertical wall, because it forces pressures to generate
out through out the body. This distance is way to great to have oxygen diffused from
here and I don't know what you do over here so when you have blood vessels that lead to
these to have capillaries blood within in here, those are called coronary arteries so
when you hear about a triple by passes there's three places within the coronary arteries
that are plug and they take another vessel and by pass that blockage it's a detour.
This just illustrates this, so again the left side, the left side is remarkablyﾊ I mean
dramatically thicker than the right side. Don't use the commonly septum use the outside
wall. So this shows you the C pluck here so, we have liver here, the liver is huge.
Lots of proteins for blood clotting. Because you don't want to go straight into
the bloodstream. So there's the liver here. Huge.
This is the diaphragm. Separate the abdominal and thoracic cavity. It gets pulled down to
cause inhalation, here's the lungs, here and stuff.
Here's the heart it was inside the pericardium so here you see the pin A and the past the
lab exam involved actual dissections with 30 stations set up you a minute and 45 at
each station when time was up you go to next station and then the next station, some Stiles
stations would require more time than others, we won't be doing that this time instead lab
exam 2 and we'll talk more about this next time will consist of 1 exam it will be a printed
exam. So I will have color imagine images you free to spend 20 minutes on one question
or you can spend 30 seconds on it and move onto next.
I'm not a huge fan of this because color images aren't nearly good as the dissection but we
can no longer set up and we can't set up 3 exams in 3 hours that's the limitation there.
So, here's a heart here, it wasn't inside of the pericardium which created the paracardial
cavity. Here is the heart dissected here this is left side this, is the right side you can
see this is dramatically thicker than this, this is the common wall. Leer's one of those
AV valves and in this case its on the left side, so what AV valveﾊ I know it's the
left AV valve but what's the specific name? Buy cuspid. Now if you want a way to remember
this, you can remember try before you buy. But keep in mind, that blood flow is occurring
in both sides of the heart simultaneously so it is not like, you know, this isﾊoccurring
before this, just happens in the pathway this is deoxygenated this is oxygenated if you
will making blood pressure measurements in the lab. That means you'll be taking the pressure
by the vertical we don't want you seated for this, we have a stethoscope please use the
alcohol wipes to clean the ear pieces. Both before you use it and after you use it. Okay.
And what you do is you have a [Indiscernible] there's a cuff here and you're going to take
an apply external pressure, increase the pressure and it's basically like squeezing you will
squeeze this artery here onto the bone and when the pressure equals the pressure within
the artery, you block blood flow so you'll raise the pressure higher you that and you'll
slowly release the pressure and what happens is when the external pressure just equals
the internal pressure blood will squirt through the opening and you'll hear that with the
stethoscope as turbulence so o that value you record as you're lower this is systolic,
when the value disappears that's the diastolic tick, is the blood flow [Indiscernible] so
realize when you do the pulse here, or here or wherever you want to do the pulse, you
measuring that pressure that pulse of blood, right?
Generated by the left vertical. So here, you're measuring the pressure here,
generated at that, we want you to seated because the standard values are taken at that position,
plus if you faint, and it's happen the distance to the floor is less.
So, it's the safety issue. Okay.
Lots of fascinating things, there are some hospitals when they do open heart surgery,
you canﾊ and I use to have a link that's no longer active anymore you can e mail them
during the open heart surgery and ask questions of the surgeons so the surgeon also narrate
this and then they take questions from people online and then answer them. So there's some
amazing things you watch, so if you have a chance spend time doing that, it's fascinating.
In terms of the lung this is showing you the gas exchange so air comes through the nasal
cavity or oral cavity goes into the lungs for gas exchange, this just shows you huge
surface area, for exchange occur at the alveoli, we'll spend a long time talking about in terms
of inhalation you'll see the diaphragm in the rat, I hope I can show you that, the diaphragmﾊ
if you go to grocery store it's called skirt steak, for fajitas it's called squirt steak,
how many have heard of term it's the diaphragm. When you inhale you pull this diaphragm down,
the lungs are effectively clued and they're not clued but effectively clued to the outside
when you change the volume, like if I had a balloon and I can pull on the balloons if
the balloon were glued to my fingers, if I do this I would stuck air in and if I do this
I would suck it out. We exhale through positive ventilation. Frogs,
are positive ventilator they fill up the chief executive and force the air in. We're negative
ventilator here are some questions, will ask you, you should be able to answer them. Skeletal
system, please be aware that you know, not only does it support generation of force.
Pivot points. Attachments of the muscles the other thing is, storage of calcium and phosphate
you should know the bones here, listed, I guarantee you I will have a diaphragm of the
skeleton on the lab exam and say, identify this bone, etc.
So, digestive system know the parts of that. Soﾊhere's some imagines that I'm going to
quick do the dissection. Male, female. Scrotum with testicle, nipples here.
Here's the dissection the rats will be warm, please dissect them this way you don't need
to wear gloves, I won't wear glove when he is I go this section. Take into the cut, do
not cut into the abdominal wall you're strictly cutting the skin and what you're going to
do here is you want to do skinning quickly. You do not want to use the blunt probe and
gently go back and forth like this. What it will do is raise a lot of fur off of this
and take you a long time and likely you will damage it. Take your fingers around separate
it. Little pressure, if you have known allergies, please tell us, we have respiratories in the
lab you can wear to minimize this, we want to do this the rats have been washed the alcohol
and they're slightly damp to minimize fur going around, one of my GSIs is extremely
allergic to rats we can't let her go into the lab rooms we can't have her students grade
papers that have been in the lab rooms sox if you have a known allergy, if during lab
you're feeling faint headed, really itchy, quick leave the premises and go outside we
have had some reactions occur. So anyway.
So the dissections are going to be like this. In the neck region I want to go other things
that students have trouble with. Some glands are easy to see.
Here's the medial line, this is the gland here's yellowish or green up here. Lack mow
gland or tier gland is here. Rats don't have tears for emotion, but they still have tears
to keep they're eyes moist for gas exchange, they have lysosome for [Indiscernible] but
lysine bacteria that will kill them so they produce tears.
They lymph nodes are up here there's small up here. Make sure you identify these structures
up here in the neck region. Okay.
When you go to the abdominal cavity the cecum is huge, here's the liver here you'll want
to pull the GI tract to the side this is the xiphoid process that's the landmark that you
use for CPR, right. So, once you pull out the GI tract to the
side here's the diaphragm here, separating the abdominal cavity from the thoracic cavity.
Here show it is female to remove the rib cage cut laterally, down to the midline because
if you do more than likely you'll puncture the heart or blood vessels, so cut laterally
to remove this rib cage. Okay. Here you can see we've cut into the thoracic
cavity we can see the heart here the lungs here you can do a cannulation, [Indiscernible]
later on you'll expose the trachea cut between some of the [Indiscernible] rings that prevent
collapse. Cut there, stick that plastic pipette in there and you can inflate the lungs, you'll
be able to do that, here shows this, when I took biology this is what we did on the
live rat. And we can put chemicals that absorb oxygen verses CO2, here we've inflated the
I think lungs here you, see the thymus here, that's kind of hard to see.
Here shows you the bladder. This is a male, this is apostate gland here.
These are fecal pet lets within the GI tract. Here shows a female [Indiscernible], females
have this uterine horn, humans don't have uterine horns. I'll tell you later of a student,
wife. Anyway. Ovary here, fallopian tube here.
Hereﾕs the pancreas, this is one otherﾊstructure that he is a hard to find. Put this on the
board the easiest way to find this and hopefully I'veﾊ so here's the stomach like this, the
esophagus going this way, it will pass through the diaphragm, we have the small intestine
here, the 3 parts of the small intestine, jejunum and ileum.
Small intestine here, the pancreas is right here, so if you look at the [Indiscernible]
and of the small intestine and stomach it's the pinkish tissue, once you see it you'll
see it's diffusion through out. So that's what this is illustrating here. There are
two parts to it. Here's the pancreas here, and then you see
it's diffused through out. Kidney is here, the spleen there.
The adrenal gland is here above the kidney, anterior and you'll see that the blood vessels
that lead to it. This is someﾊ things about adrenal tumor, affecting behavior, this shows
you the GI tract pulled out if you want at the end of lab feel free to pull out the GI
tract, you will pin the rat using dissecting pin we would like you to count the number
of pins when you start and also count the number of pins when you finish, so you don't
believe any extra pins in there, we are using these first as a teaching tool and then we
donate all of the dissected rats to an organism that rehabilitates wildlife. If you leave
a pin in there and the bird eats it you kill or injure the animal. These are common errors
done on humans where spunkings are left in space and stuff they do counts if we have
time I'll talk to you about some of those mistakes during surgery.
Here's the ureter, leading to the bladder down here, the way to kind it is here is the
kidney, the urea has to lead to the bladder so take the blunt probe, push back against
the body wall like this and pull to the midline and when you do that, when you get the ureter,
it's a nice thin like you'll see the kidney move a bit that's your clue where the ureter
is and you can pull it out. In terms of the reproductive system this is a frontal view
here this, is a side view here. The structures within the rat that you'll
need to know for the male will go over a view of them right now. Here are the similar vesicles
here they're easy to find. The coagulating gland is here, that is difficult
to find it's the darker structure at the base of the [Indiscernible] vessel.
Coagulating gland changes the viscosity of the semen. But it's to viscus the sperm can't
swim. Here's the bladder, filled with lots of urine. Here's the vesicle here, it was
inside the scrotum, what you need to do is squeeze on the scrotum, push the testicle
through the abdominal wall and out, males hate to do it they're squeamish.
I understand. Anyway.
Kidney here, I say kidney. Testicle. Here's the vas deferens, right there's the
prostate so within this, there will be two [Indiscernible] we'll talk about.
Cata and kaput. And cata is this one here, it's closest to
the vas deferens so on the lab exam, which part contains the most mature sperm would
be the cata epididymous. That's the vas deferens here. You see the vas deferens leading here,
lots of fat to cushion this testicle for protection heartiest cata, the kaput here, here's some
blood vessels that supply the vesicles with nutrients and that.
Here's penis pulled out. That keeps the bone within the penis with the female when it Capulets
it has a hook on. This is a preputial gland there, it secretes various scents like musk and that
say I'm male or female. And also if they're productively mature and if they're ready.
Okay. For the female, females going to be easier
to identify we have the ovary, leads to the fallopian tube, this is from a human, on the
rat there's two huge large uterine horns so on the rat, leer's the horns here, the ovary
is fallopian tubes the white tubes there and this is ordinary here and many embryos would
implant along the tract. Here's a close up showing you the ovary here.
Lots of fat here you can see all of the blood vessels clearly illustrating that this is
a true coelom. Because this organ here with that epithelium the peritoneal, we often call
this mesentery, around this just shows you this pulled up. And then this is a pregnant
female rat, here's the embryos implanted along the horn and vice versa. So,