What's coming up next in the world of bio?!?!?!

The next chapter we will be going through is on the structure/function of the cell membrane and cellular transport.  Here are the areas of the keystone exam we will be covering

To get a sneak peak at this weeks content - check out the video below.

Monday and Tuesday Daily Questions

Daily Questions  Monday October 22nd I look under a microscope and see rigid cell walls and green structures inside cells.  Because of this what can I infer about the cell?  That it is most likely a plant cell.  Just the presence of a cell wall does not automatically make it a plant cell because bacteria also have cell walls.  The presence of the chloroplast does that indicate that it is a plant cell. Some disorders are caused by a lack of lysosomes in the cells of a particular tissue, what would result from this? (what would happen in the cell?)  Since lysosomes aid in breaking down cellular "junk" and removing it from the cell the lack of those would cause a build up of wastes and the cell would become "toxic" If the golgi apparatus was out of order in a cell, what would the direct result of that be regarding protein production and transportation? Since the golgi apparatus is responsible for putting finishing touches on proteins that were made in the rough endoplasmic reticulum, it these were out of order protein that were meant to be shipped out of the cell would not. Tuesday October 23rd A Scientist observed a protein that had been processed in the endoplasmic reticulum of a cell and then entered the cytoplasm.  Where will the protein most likely go next?        A. It will move to a ribosomes that will release it outside the cell      B.   It will move to a ribosomes to be packaged in a vesicle for transport      C.   It will move to a golgi apparatus that will then release it outside the cell        D.  It will move to a golgi apparatus to be packaged in a vesicle for transport

Which statement BEST describes the role that is common to chloroplasts and mitochondria in plant cells?      A.The both use light to produce energy       B They both are involved in protein synthesis      C.They both convert organic compounds into ATP      D. They both are involved in energy transformations

Which structure and function are common to both prokaryotes and eukaryotes?      A.Mitochondria that generate usable energy for the cell      B.Mitochondria that control what enters and exits the cell      C. A cell membrane that generates usable energy for a cell     D. A cell membrane that controls what enters and exits a cell

Ribosomal subunits made of protein and Ribosomal RNA are assembled within the nucleus.  To which organelle will these ribosomal subunits MOST LIKELY be transported?     A.Vacuole      B.  Mitochondria      C.  Golgi apparatus       D.  Endoplasmic Reticulum

Which feature is common to all prokaryotic and eukaryotic organisms? a. Endoplasmic reticulum that stores fat reserves b. Ribosomes that produce complex carbohydrates c. Nucleic acids that code for genetic characteristics d. Mitochondria that are sites for cellular respiration.

Organelles Wrap Up

We started with daily questions from older material (on the introduction to cells and the cell theory)

Thursday October 18^th

The cell is the basic unit of Structure & Function in all living organisms.

The human body has about 200 different types of cells with VERY different functions.  What determines the function of a liver cell compared to a kidney cell? The structure of the cell.  Remember, all cells have similar structures found in them but they look incredibly different because they have incredibly different functions.  Below are some pictures of different eukaryotic cells.

Liver Cells

Kidney Cells

Lung Cells

 See how each of these cells have VERY different strcutres because they have VERY different functions!!




The main difference between prokaryotic and eukaryotic cells is the presence or absence of what? A nucleus.  The term prokaryotic literally means "Before Nucleus" or "Before Kernel" because have no nucleus and they are much more primitive than Eukaryotic cells.  Eukaryotic literally means "True Kernel/Nucleus" because it DOES contain a nucleus.What are three features of a cell that are common to both prokaryotic and eukaryotic cells?While prokaryotic and eukaryotic cells are very different, they ALL contain DNA, are enclosed in a cell membrane, are filled with cytoplasm and contain ribosomes

After this we had a brief discussion on the organelles and we answer the following two questions together as a class.

The structures found in a living cell can be compared to the parts of a factory that produces cars. Which part of the factory is most similar to the nucleus of a living cell?

(1) a conveyor belt that transports materials (Incorrect - that would describe either the endoplasmic reticulum or the golgi apparatus which transports proteins)

(2) a storage bin that holds the pieces needed to assemble a car (Incorrect - that would by the vacuoles)

(3) the computer room that controls the assembly process - Correct!!!  Since the Nucleus stores the DNA, it basically is in charge of EVERYTHING that happens in the cell!

(4) the generator that provides energy for the factory (incorrect - The generator would be the mitochondria which converts organic molecules into usable energy.)

Certain poisons are toxic to organisms because they interfere with the function of enzymes in mitochondria. This results directly in the inability of the cell to

(1)  store information (Nope - information is store in the nucleus)

(2)  build proteins (Nope - Proteins are built in the ribosomes)

(3)  release energy from nutrients (DING DING DING!!! That is correct!)

(4)  dispose of metabolic wastes (nope - that happens in the lysosomes!)

After this I passed out a worksheet that first made you match up organelles with their functions and then started to apply the function of those organelles with different disorders.  Using the examples I have done in class, i asked you to choose the correct answer AND tell me what is wrong about all the other statements!

DAILY QUESTION QUIZ TOMORROW!!!!!

Cell Structure and Function

Well it has been a WHILE since I have posted on here guys!!!  We are full force into our chapter on cell structure and function.  You have all the notes you need on the cell theory, the two types of cells (prokaryotic and Eukaryotic) as well as the different organelles and their functions.  We will spend a little more time going over these different organelles and how they all work together to make a cell run.

We did have daily questions today and last wednesday.

Wednesday October 17^th

These groups of cells represent different

(1) tissues in which similar cells function together

(2) organs that help to carry out a specific life activity

(3) systems that are responsible for a specific life activity

(4) organelles that carry out different functions

Which sequence lists the levels of organization in the human body from simplest to most complex?

(1) organ system >tissue >cell >organ

(2) tissue >cell >organ >organ system

(3) organ >organ system >tissue >cell

(4) cell >tissue >organ >organ system

Tissue is composed of a group of

(1) similar cells working together

(2) different organs working together

(3) organ systems working together

(4) nuclei in a cell working together

Humans require organ systems to carry out life

processes. Single-celled organisms do not have

organ systems and yet they are able to carry out

life processes. This is because

(1)  human organ systems lack the organelles found in single-celled organisms

(2)  a human cell is more efficient than the cell of a single-celled organism

(3)  it is not necessary for single-celled organisms to maintain homeostasis

(4)  organelles present in single-celled organisms act in a manner similar to organ systems

Wednesday October 10^th

If a cell is like a city, what part of the cell would be the: 

“control center” - The Nucleus

“Recycling Center” - The Lysosomes

“Post Office” - The Golgi Apparatus

Investigating Digestive Enzymes Lab

You guys were able to experience your first "read the procedure and DO it" kind of lab and we all managed to survive?!?!?  Friday we had the opportunity to share the results we observed in the three different set ups.  If will briefly detail the initial and final results here - but please go to Edline and click on the lab where I have uploaded a full presentation of your results.

Procedure A looked at the effect of temperature on the digestion of lipids.
Each test tube contained a pH indicator (that turns pink at a pH above 8), Olive Oil (a lipid), and a mixture of digestive enzymes.  Initial observations were the same for both tubes

One tube was placed at room temperature while the other was placed at body temperature (in an incubator) and set overnight.

Here were final observations

Procedure B also was testing the effect of temperature on enzyme action but this time it looked at enzyme activity on Starch.

Each test tube had a starch solution, a mixture of digestive enzymes, and an iodine solution.  The iodine solution turns a dark blue/black in the presence of starch.  Here is how all three started.

Test tube 1 placed at 5 degrees Celcius, 2 kept at room temp and
 3 placed in the incubator at 37 degrees Celcius (body Temp)

You can see that the one placed in ice is still a dark blue color
while the room temperature is a very pale blue and the body
temperature one is completely clear (meaning there is NO starch
left!!) 

And finally we had procedure C which looked at the effect of pH on enzyme activity.  In this case we looked at enzymes activity on proteins.

Each test tube received a piece of boiled egg white and pepsin (a proteolytic enzyme).  The changing variable in this case was the pH.  One test tube had an acid added to it (Hydrochloric acid), The second had pure water (neutral pH) and the third had a base added to it (sodium hydroxide)

Set up

The constant variable here was the temperature.  ALL of them made their way into the incubator to work at body temperature over night.

And here were final observations.  The protein which was placed in an acidic environment (like that of our stomachs) worked the best and completely digested the egg.  The one at a fairly neutral pH did not do much at all while the basic test tube had slight enzyme activity.

We will continue to draw conclusions about enzyme activity on Monday!!!

Continue with enzymes and pre-lab for digestive enzyme processes

Daily Questions from Wednesday were based around your notes on enzymes and their functions.  All of these were sample questions from the keystone exam.

Wednesday September 26th 

Which statement explains why large changes in pH can affect the functions of plant enzymes?

1.  Large changes in pH increase the rate of cellular chemical reaction.

2.  Large changes in pH provide the energy necessary to activate an enzyme

3.  Large changes in pH can denature an enzyme causing a change in its shape.

4.  Large changes in pH can cause an enzyme to react with a different substrate.

Z could be replaced with either pH or Temperature.
Both of these effect enzyme activity.

Molecule c would most likely be the substrate of this enzyme

 We continued the notes on enzymes yesterday and finished with how temperature effects enzyme function.  We then did some pre-lab work on digestive enzymes and today actually went through the lab.  This was the first time I had you guys actually READ through a lab and do it all yourself.  It was a BIT chaotic, and only one beaker was broken (my fault) but we were able to at least get the procedures done.  Once I have all the pics and we get final results I will post everything that happened during the lab.

NO DAILY QUESTION QUIZ TOMORROW!!!!!!! We will just continue to work through this lab!!

Enzymes - My kind of molecule! They are TOUGH and they are WORKERS!!

Tuesday September 25^th

Enzymes are CRUCIAL in allowing biochemical reactions to occur – How do enzymes aid these chemical reactions?

By LOWERING the activation energy required to start chemical reactions.  Without enzymes our bodies would not perform biochemical reactions quick enough to support life.

Enzymes have three main parts –

*What is the area binds a substrate?

 The "Active Site" - this is a restricted site on the enzyme where a SPECIFIC molecule involved in a chemical reaction bind.

By heating an enzyme up the shape of this site can be altered.  Why do you think this could this have a DRAMATIC effect on the function of the enzyme now?

If the shape of the active site is changed, the specific reactants that would normally fit  will not be able to bind any more.  For instance - take a look at the Enzyme Hexokinase (blue molecule) below.  This enzyme binds glucose (red molecule) specifically.  If after heating this enzyme, the active site changes, glucose will not longer fit and the enzyme will be inactive.

Using the graph below that displays enzyme action - determine which time interval the enzyme initially affects the chemical reaction.

It would have initial action during the 2nd time interval.  This is the point where activation energy is required for a reaction to occur.  The enzyme lowers the energy requirement for the reaction to them proceed.

After these daily questions we continued with the notes on enzymes.  Yesterday we focused mostly on what is required for a biochemical reaction to occur and the role that enzymes play in that.  Today we focused most on the different factors that effect enzyme activity.

**Just as a note - These were Friday and Monday's Daily questions if you didn't get those down!!  They were just wrap ups of proteins and nucleic acids.

Friday September 21^st 

Proteins are made up of what kind of subunits (Monomers)?  Amino Acids

Proteins are very complex and their functions are very diverse – what about proteins determines their function?

 Their Shape and how the amino acids interact with each other.

The last organic molecules we will be looking at are Nucleic acids – what are two examples of Nucleic Acids? DNA, RNA, ATP

Monday September 24^th

Nucleic Acids are made up of what kind of monomer? Nucleotides 

This monomer has three parts – what are they?   A sugar , a base (nitrogen base) and a phosphate group

What are two important functions of Nucleic acids?

Store hereditary (genetic) information - in the form of DNA and RNA.  They also act as energy carriers in the form of ATP.

Steroids, Jello and Cow Bones Oh MY!

Thursday September 20^th

Looking at the following chemical formula, what kind of biomolecule would you infer this to be?  Why?

               C₁₉H₂₈O₂              

 This would be an example of a lipid.  You can tell by the large number of Carbons and Hydrogens.  While there is a FEW oxygen molecules - it is not anywhere CLOSE to a 1:2:1 ratio.  This is in fact the structural formula of Testosterone which is a natural steroid hormone found in our bodies.

Proteins have MANY different functions – in fact proteins are pretty much involved in ALL cellular functions in one way or another.  The structures of these proteins are incredibly complex.  First, what subunits make up protein? Amino Acids

Next, what determines the function of different proteins?  The shape and how those amino acids are folded on top of each other.

After this we continued through the notes focusing this time mostly on proteins.  We saw that the range of proteins is ENORMOUS.  I had you jot down a couple of the following examples and let you listen to a podcast about the source of the protein found in Jello.  Here a link to the transcript of that Podcast

http://blogs.howstuffworks.com/transcript/what-exactly-is-jello-made-from/

Tomorrow I would like your "chemistry of Health" worksheet and writings.  We will also take a daily question quiz and finish up with organic molecules tomorrow.

Carbohydrates Vs Lipids

Yesterday we got through most of our discussion on Carbohydrates and that is why I based today's daily questions on that.

Wednesday September 19^th

Carbohydrates are made up of what three elements in what ratio? Carbon, Hydrogen, Oxygen in a 1:2:1 Ratio (Remember, Carbohydrate literally means "Water" of Carbon, for every Carbon atom there is 2Hydrogen and 1Oxygen (H2O) )

What could you infer about a carbohydrate that has 12 Carbons (such as sucrose)'s chemical Formula?

That it would be C12H24O12 (1:2:1 ratio)  We see that in fact sucrose's chemical formula is ACTUALLY C12H22O11 due to how it all bonds together, which is CLOSE to the 1:2:1 ratio but that will not always be exact)

Other than a source of energy – what other function do carbohydrates have?

It acts as structural support to plants (in the form of cellulose) and certain insect's shells.

It also acts as a "name tag" attached to the cell membrane of EACH of our cells identifying which cell's in our body they are AND WHOSE they are (which is why organ transplants are so complicated!!!)

Which can store more energy Carbohydrates or lipids?

LIPIDS!!! Why?!?!  Take a look at the following two molecules

Lipid

Glucose

You can see there lipid molecules are made up of MANY more Carbon-Hydrogen bonds and energy is released when bonds are broken.  Because of this, lipids have the ability to STORE more energy - than carbohydrates but the problem is, it is harder to GET to that energy and our bodies will work through our glucose stores FIRST.

To put this in "real" terms I mentioned to you guys today about my upcoming marathon and how generally I hit the "wall" around mile 21 or so (it STARTS around mile 18 and progressively gets worse)  The BIOLOGICAL reason behind the "wall" is, at that point I have pretty much used up ALL my glucose stores and my body is breaking WHATEVER biological molecules it can apart in order to release energy.  Which means PROTEINS (like in my MUSCLES) are getting tore apart to get energy. THIS is kind of what mile 21 sometimes looks like (this was my FIRST marathon - they have got much better since then ;)  Here is a link that describes it in even more detail. http://www.marathonandbeyond.com/choices/latta.htm 

Mile 21 in my FIRST marathon

Mile 23 in the last marathon I ran (yep - sporting
my Ellwood Gear!!)

After this we continued through the notes on lipids and started into the differences between saturated and unsaturated fats.  We will hopefully be starting a activity on this stuff by friday.

Great Job today guys!!

Importance of Carbon and start discussing Carbs

Tuesday September 18^th

Organic compounds that make us up are made up of many atoms of which element?  Carbon

Why is this element so useful in making macromolecules (large molecules)

It is relatively small - it is Kind (it likes to share it's electrons with many other atoms such as Hydrogen, Oxygen, other Carbon atoms and Nitrogen) and it can bond with up to FOUR other atoms at once.

How many valence electrons does this atom have that can be shared with other atoms?

4 - so therefore it wants to find other atoms that will fill that up (hence why it could bond with up to 4 other atoms)

The four primary biomolecules that make us up are:

Carbohydrates, Lipids, Proteins, Nucleic Acids

I had you guys watch the beginning of Hank Green's "Crash Course Biology" on Carbon.

Then we got through carbohydrates in the notes.  We will continue through these notes over the next couple days - remember - This friday we WILL have a daily question quiz!!!