1.1 what is biology-cc.mp4


Uploaded by tasneem6084 on 08.05.2012

Transcript:
Welcome to general biology for non-majors.This is the begining of our first week. Our first week is going to be mainly explorimg the term for biology
understanding of some of the key terminology system as to how we will start discussing the main concepts and in this class. Now let's look at
"biology" which has two parts and in it's word; the first part which has bio mean "life"
and "logy" means study so in real scenario biology does means
study of life.
Just as the word tell you: Biology
when we say life then what do we mean by life?
how do we differentiate
living organisms from non living organism there are certain properties or attributes given to living creatures
the greatest organism and we will explore them in a few minutes, before we go on keep in
mind that the knowledge of biology is mainly based on nature and nature is organized in a very unique pattern
and then it has because of various levels of organization
and various other organization we are talking about a small little bacteria which is invisible to the naked eye
as compared to a large tree or a large donkey or a monkey or small fungi or an algae. So there are different levels of organization in this unique
discipline and there are various
aspects of understanding biology. General biology for non-major is basically designed in such a manner that the semester long experience
will give you a sense of what is present in the discipline and how the discipline is explored.
we will began our discussion with mainly starting with the study of cells and get into the organization of cells.
we will come next look at the various
reactions or the metabolic processes that goes around the cells. We will then look at the growth or cell division that will study a little bit of
biotechnology you will study environmental biology and ecology and
conclude by the study of plants and animals. So the old thought that biology's is the study of plant and animals is not true anymore.
anymore because the discipline has grown and then exploded in the last couple of decades. So le'ts look at certain properties of LIFE.
the first property of life is the organization and this is so complex that I will skip for the minute and we will go the next slide
exploring this organization. Metabolism
is the sum total of all reactions that carried out by a living organism. Metabolim will also include the reactions which would help you to digest food
and energy that is provided for a movement for walking or for swimming or for hiking.
or how plants store, how they grow in size. and how they respond to certain stimulus about all going to be a lot of chemical
reactions that we will study within metabolism. Growth is the next property of life, if we see a rock vs a plant we will associate life with the plant
and not the rock. Why? Because the rock never really increases in the number or in size. It can get crush which is not really
increase in mass, while the plant however can
grow and increase in number and cell quantity and also an in size of the cell. I want to point out that of the cell line to point out to
there is a term called unicellular which means that
an organism is only composed of one cell. Now theoreticall this one cell is not going to grow humongous that it will be large
as this mouse overhere. Unicellular cells will then form
connections with more cells and will form what are called as multi-cellular organisms
and a multicellular organisms have thus increased the number of the cells
Yes, certain bacteria will grow from a tiny cell to a little higher dimension but the increase in size is relatively definitive. However more living
organisms will definitely grow in number and increase the number is going to be associated
with certain kind of cell divisions that we will explore within the semester.
The next concept is adaptability. Living organisms definitely have to adapt to the environment this pretty much leads us to the
next concept of evolution. By this we mean that certain birds are present in a certain region where there are more
stocky fruits to eat with then birds with the beak will not survive their better so they will have to fit better with environment and the
process of this is done through evolution and natural selection
However the adaptibility, can also be related to a certain changes in pH, certain changes in temperature, altitude and so forth.
Irritability is that living organisms can definitely respond to any kind of external stimulus so pretty much even if you take the
pin and poke yourself in your hand your reflex will
be the hand will pull back.
dogs and cats have a reflex as you can see the tail of the cats starts rising and many animals have very strong responses to
external stimulus. Certain organisms are very responisve to
changing in the climate for whether they will be able to relate to it to these are certain properties off living organisms and non-living
organisms would definitely be missing these. Now let's look at the first of terminology which I'd skip and that we decide which is the organization
of let's look at hall of organized the living creature are. The basic structure of the
basic fundamental block of many living creatures are cells but the cell is also organized
from the molecules and molecules are made up of atoms to let's go back and see how this organization is coming out, atoms would be
something like carbon that I can write out a atom of hydrogen and oxygen these are elements present in the environment and in our world
and that will be organized to form molecules to for example if I need that I'd written oxygen together of the
molecules that con be formed such as H2O or water, the hydrogen gas or I can have oxygen as O2 which is the molecular form
is the molecular form of oxygen to itself into an end to end a samples of oxygen
and hydrogen and water and these are all molecules because moleculees are made up of more than one atoms, now certain
molecules that we will learn in the coming chapters can be
form an chains of moleculesr larger molecules and are called as
macromolecules. Macromolecules than align to form
the the region that is present within the cells. The cell is a basic
structure of living organism, the cells of similar kinds will form
form to issue, is for example if you have of that of connective tissue that cells off your muscles will collect
and organize in one region and form tissues. for tissues. Different kinds of tissues for example cardiac tissue connective tissue
of bone tissue and then form of different regions which are causing organs organ start and end of the together in a more structured format before
organ system for example the digestive system is not just made up of his stomach it's an intestine, your mouth region of and
your osephoges and so forth. Organ systems then get organized to form
organisms and organisms of are definitely going to be made up of one or more cells now this is
a sort of a flowchart off all different levels off organization exists from a simple atom
two of the largest biosphere and the earth we call is biosphere one and of the becasue it has got a whole collection of not just the plants and animals
and microbes and environment so this is the sort of a biosphere one. Biosphere two for those of you were living there is Arizona you know
there's a biosphere two in Tucson, Arizona but but we will get ecology later in the semester.
for you to understand is a different terminology.
Different biosphere can then be grouped together to form different populations. A population for example can be a group of
collective individuals that are present in one specific areas for example if you're looking at the Marine ocean and then is that if
the author of a population of from various single cell or multi cellular organisms
that are very specific in the region of the ocean in this particular example is from the fish species in the Red sea. Now within the Red sea
not just the fish are present along with that we have the Corel reefs we have of other kinds of algae and this will form a community also a
different populations are present in a specific area.
Now the Red sea will be associated with not just what is present with the community but also look for the outputs of energy and materials
around it. and some pretty much how does a good flourished
where is it present geographically and you can look at the picture in the book in you can see that its present and in the Middle East from
around the red sea and and eventually all regions of the earth will hold together to form the biosphere
so we have of all these levels off organizations from Atomss to the largest which the biosphere,
So what is all these organism require? the most important requirement for all organism is energy and
because energy is not just required for a cell to grow all but also to a organize different kinds
of reactions, different activities within the cell .
Where is this energy comes? the energy is ready coming from the nutrient's that the organism is depending on so whether it's a consuming
indirectly or whether it's taking it from the environment
of certain nutrients are required for growth and survival now there are that two kinds of organisms
those that can produce their own food and those that depend on others
for example the first one are the producers and these are going to be your plants or certain bacteria that is also because
producers because they can manufacture their own
food. They take input from the sun or use carbon dioxide and some of them can take
of methane and they can survive and they can make their own raw materials
consumers are are on the other hand usually animals because consumers will depend on the
producers do then to form or gain the energy to this is a matter also of
continuous flow of energy
Organisms definitely respond to a change as there are various receptors present of that will stimulate cells within a certain region
and of the simulation can be taken into account even for something like bacterial cells that has certain receptors on the cell membranes
and cell walls. It can respond to stimulus for certain bacterial for example if I draw the bacterial cell over here from that is a pneumonial bacterial
it actually has a thick coating outside which is called as the as the cell capsule for the wall and it prevents the from
bursting
let me right the name of this bacteril, The coat will will help them that to survived because it will help but not respond to a
certain stimulation on the outside in this could be even a such as of a drastic effect of that of a change in pH.
either very high.
cells are continuously exposed to this display for responding to certain stimulus then it will be very hard for a cell to survive now of
it within our internal chemistry we do have a mechanism was called as HOMEOSTASIS which
means out we respond to certain conditions through a range.
Homeostasis will be how to respond to a stimulus to that is not drastically destroyed the cell. And they will also explore these in the subsequent
chapters but let's go on to the next slide. Pretty much you have seen that so far that I've been focusing on
organization of the living cell and it's a must. Organization is basically
present in the study called genetics, the genetic code is present in what is called as the DNA; which stands for
Deoxyribose nucelic acid.
and this is the genetic code and this is the code of life and this has all the information on what an organism shoudl be and what sort of reactions
the organism is going to undergo and what is the appearence of the organism what kind of diseases that the can
stored in the DNA and of course you can pretty much see that the DNA is inherited
from the parents to offer insights inherited a code of life that is coming
from the parens
Development is another term development means that how a cell
arises to an adult for example I can get a good example of this one for example if you
have eggs of some creature and this creature enentually turns into a butterfly
you can see it has gone from various stages of development and first formed a larva and from a larva to a state that is called as a
pupa stage and then into a butterfly. So development is the series off processes are
stages that the cell under goals to form an adult or
a organism
So looking at all this unity organization among the species and then gives us up a whole new dimension of how to
understand me some hope these organisms together
and these are grouped through a system that is causing classification system. Classification system is pretty much organizing
species and very exclusive groups.
The latest concept is about the domain system and I'll get into it in a little while.
Each organism is considered name to a specie name has two parts it's got the first part and the second part the first part is suing
the genus name and then you have the species name for example
of that only humans of policy Home Sapiens where homo is the genus and spaiens is the species name.
a tomato plant is called as Lycoperscicum esculentum
Lycoperscicum esculentum
let's get the right spelling of the real long names of calming a tomato idea has two parts
the first part of the genus name and the second part is species name.
I used previously the word Domain all the domain of all these organisms a grouped into three major domains of the end of the first domain is called as
the Bacterial domain and usually consist of all single cell and the single cell are all prokaryotes and we will spend good amount of time on them.
what they are? example right now from prokaryote is going to be a
cell that has no true strucutres inside so to comparet to a eukarotes carryout for example have structures
are causing carryout send out a nucleus inside the mitochondria plant cells may even hadve cholroplast.
all these membrane bound structures are present inside are eukaryotes. A prokaryote will be
a cell that does not have membrane bound structures. Cells of Bacteria and Archea of the two domains which are being studied for division
within kingdom division within these two domains. And we will spend the amount of time and then as a semester going through all of these
Archaea are the most primitive of creatures of these are present and for example
in Sulphur Springs and of very deep oceans, hot springs and
these are the most primitive kind of organisms, these are the prokaryotes and these will be the bacterial kingdom and the last domain is
called as the eukaryotes
eukaryotes
have lots of structures, if you think of a cell as a house a prokaryotes will have one large area with no differentiation between the
kitchen in the bedroom or a living out and the eukaryotes will have the organization of different compartimentliazaion with the cell.
and that is what a eukaryote is. Eukarytoes are divided into different kingdoms.
some of them are named here, the protist are the simpest over here, an image of euglena or
chlamyodmonas or it looks like a euglena or a paramecium, plants would be a something that are green fungi would be
your mushrooms and plants would be your kingdom that I think you already know in animal kingdom would be the ones that will
have all the animals with other birds and reptiles and mammals. So remember there are three main domains the first two domain
the kingdom are not yet studied so we don't know all the contents within that there's still the
research going on to put them into different kingdoms
Now we will explore up a different part of this because lecture and that is about critical thinking and science, earlier you understood what
biology is, any of you understood about discussion on domains now how all
this from thought process is carried out. Science is a way of gathering data, makingn observations
performing experiments coming up with cetain hypotehesis.
The study of science is based on critical thinking of getting goaltending is not just the gathering information is what you've learned and how
what you have learned can be applied to a certain scenario and I will try to help you develop this during class we're doing it quiz
will be taking more you just you often find certain questions may not be direct question to you have you have information and now is a time to apply
what you understood to so critical thinking is an important aspect of science. Science is based upon
judgments we almost have to have from a data that needs
to be analyzed. Researches of them do that by the less certain steps of the call is a scientific method and then
your first lab that you'll be doing is based on the scientific method the salsa or the coat lab!
We have something called observation observation is observing something
in nature of phenomenon and a after you have observed you pretty much collect what is called as
data so after observation you collect
data from the data that you will make certain of
the sensible guesses and the sensible guesses are called hypothesis now remember it is still a guess is an assumption to the
tested and these tests would come through experiments. Hypothesis have to be
experimentally tested so ones that experiment is successful then you can
call it a theory or a law as the result show up. Sometimes experiments are not succesuful if so
you have to go back and you change your hypothesis. One of the good examples I give to my classes is when you go to a doctor and you
have some sort of illness, the nurse pretty much takes your observation your vitals your blood pressure and temperature and
so forth from the Dr. comes and he gathers all the other observation that has been collected and may ask few more question
and then test the , with the hypotheses which is at a guess off once he assumes you
may be suffering from and will test you by giving you some kind of medication that of sometimes most of the time the test will work and
you'll be seeing better but if you not been getting well and you have to go back
then it's almost changing the hypothesis or in some cases or the nurse may call you next day and tell you that the Dr. would like to change
the medication that he puts you on she put you on so that is a way of scientific method.
Whenever we do experiments we alwayss have certain variables of variability is of for example something that needs to be measured against
changing. Now if you are having more than one variables in an experiment
it this very difficult to find effect of one item such as effect of temperature are on the growth of the bacteria for example if I keep
temperature and effective pH and the effect of from a solution and then try to see them grow the bacteria and it will be very hard to judge
whether the temperature really effect in this way or was it the pH. You have to have the measuralbe one variable.
Having many variables that can be very hard to do to experiment with from along with the variables you
must always have a control group of control group is pretty much something that will not change
so again when you do your exericse with the salsa lab pay attention to your variable.
is what your control group in there.
Biological systems of many variables as you can see and there are so many things that can affect the growth of an organism.
experiment will initially focus on one variable at a time. A lot of these experiments will result in a theory.
will even to results and eventually lead into some sicentific
thoeory
a scientific study will then be eventually proved over times, my favoriter examples of my favorite is the theroy of gravitaion objects will always fall
depending on how close they are from the surface of the earth.
that theory almost is a law because iit is always going to be correct. Theory of Evolution states and the changes can occur over a line of
descends, not something you will see right away to the lots of theory that with a pretty much
proven scientific experiments, this concludes our first week's lecutre. Hopefully you got familiar with camtasia any my recordings.
this way we will be listening to lectures every week
don't forget to attempt your quiz for this week!