Quiz 1 Q2 Review Sheet
Honors Biology
This is to be used for REVIEW
Quiz 1Q2 will cover:
Chapter 5: 5.10 through 5.18
Your Resources
1.
2.
3.
4.
5.
6.
7.
Your notes from class
Your textbook with bold words and figures especially
The powerpoint
Dr. T’s notes
The misc section of the website with assorted tutorials (watch these)
This review sheet
The internet in general
The Cell Membrane (animation under misc section)
1. Describe the structure of a phospholipid in detail.
2. Indicate how phospholipids align relative to each other in an aqueous solution (we
discussed two ways), explain why they do this, and be able to draw both. Which of these
ways is representative of a cell membrane.
3. This question will be on the quiz: Describe the structure of a cell membrane. What are
they composed of and how are they organized? Be able to draw a two-dimensional
membrane that includes all three types of integral membrane proteins discusses in class,
peripheral membrane proteins, IMP glycoproteins, ECM, cytoskeleton, glycolipids, nonglycosylated phospholipids and cholesterol (This is a combination of figures 5.12 and
5.13).
4. Describe the general functions of integral membrane proteins (Be able to explain Fig.
5.13).
5. Explain the terms enzyme, substrate, and product.
6. Explain the terms ligand and receptor.
7. Explain signal transduction beginning with a hydrophilic (amino
acid/polypeptide/protein) hormone. There is a great tutorial here:
http://bcs.whfreeman.com/thelifewire/content/chp15/15020.html
This tutorial is under misc section of website.
This specific pathway, which is triggered by adrenaline (epinephrine) released from the
adrenal medulla or the adrenal gland in response to some fight or flight external stimulus
(ex. A bear chasing you). Adrenaline is a amino acid based hormone. This particular
animation does not show genes being turned on and off, but remember that they usually
are in response to a hormone signal.
8. What is the difference between a ligand and a substrate?
9. Describe the functions of cell membranes. You should be able to come up with many.
What kinds of molecules are able to diffuse across a plasma membrane that lacks
proteins? How would other types of molecules like amino acids and Na+ cross? Explain
in detail on the molecular level. Do not just say hydrophobic or nonpolar. Saying that the
molecule is nonpolar and the membrane is non polar does not explain anything. Include
the electromagnetic force (charges) in your answer.
10. Describe what is meant by selective (semi-) permeability.
11. Using the analogy of the cell, how thick is the cell membrane? What is the actual
thickness is nm?
12. Describe the fluid mosaic model of membranes. What does “fluid” and what does
“mosaic” refer to? The inner life of the cell video shows this nicely.
13. Just because it comes up in the cell membrane animation, an oligosaccharide is
essentially a carbohydrate polymer ranging from 3 to 10 units long. Oligos is greek for “a
few”. Its a short polysaccharide.
Simple Diffusion (simulator under misc section)
1. Describe the process of diffusion on the molecular level. Why do substances diffuse
from “high to low concentration”? include random motion and Newton’s first law of
motion in your explanation. Draw a picture that shows this.
2. What is meant when one says that diffusion is “passive”? Explain why it is passive.
3. Explain how concentration gradients relate to diffusion. What is a concentration
gradient?
Passive Transport – Diffusion (tutorial under misc section)
1. Explain passive transport (Be able to explain Figure 5.14). Remember that once we say
“transport” we are implying across a cellular membrane.
2. Make sure you understand the difference between the movement of molecules across a
membrane and the NET movement of molecules across a membrane.
3. Looking at figure 5.14A, explain what is happening in the middle image. In which
direction(s) do the molecules of dye move? What is the NET movement? Explain why
this is in detail in terms of likelihood or probability, random motion, the 1st law of
motion.
4. What is meant by “dynamic equilibrium”? What is happening during dynamic
equilibrium and why does this happen? (again…probability and likelihood) Why is it
called “dynamic” “equilibrium”.
5. Explain why when two different substances are placed on either side of a semipermeable membrane they diffuse independent of each other as shown in figure 15.4B.
6. What is osmosis?
7. Explain the process of osmosis in terms of a U-tube (Be able to explain figure 5.15).
8. Compare hypertonic, hypotonic and isotonic solutions. Why can’t a solution be one of
these types if it is the only solution you have?
9. Explain why water always diffuses from hypotonic to hypertonic solution.
10. What does osmoregulation mean and give two examples in nature. Why is it
important that our bodies are able to perform osmoregulation?
11. Be able to explain figure 5.16 in detail. Basically, Compare and contrast what would
happen to an animal cell vs. a plant cell when each is placed in a isotonic solution,
hypotonic solution, or hypertonic solution. You should be able to explain why this
happens on the MOLECULAR LEVEL in terms of concentration gradients, probability,
why the solutes don’t just cross the membrane instead of the water, etc… Put the big
picture together.
12. You should know the terms crenate and plasmolysis and the cell types they refer to.
In which of the three states in this figure are plants most happy? What about animal cells
(most happy)?
13. Explain why if you drink salt water your brain will inform you that you are thirsty.
What is happening to your blood and why would you need to drink water to help
yourself? Also tell me why if you ever get an IV at the hospital the fluid is 0.9% NaCl
(0.9g per 100ml of water). If you were going to make an eye drop solution for people
with contacts, what salt concentration do you think you would use?
For more info read here:
http://en.wikipedia.org/wiki/Saline_%28medicine%29
14. Explain what would happen to a fresh water fish if you put them into a saltwater
aquarium and why?
Passive Transport – Facilitated Diffusion (tutorial under misc section)
1. Explain how a cell moves small hydrophilic molecules across its membrane? What is
the name of this type of passive transport?
2. Give three examples of different types of transport proteins involved in facilitated
diffusion and explain how each works.
Active Transport (tutorial under misc section)
1. Compare and contrast passive to active transport.
2. After a muscle cell contracts, it must remove the calcium from the cytosol back into
the smooth ER. Initially, facilitated diffusion will work until the concentration on either
side of the membrane is similar. However, the rest of the calcium needs to be cleared
from the cytosol. Explain how the cell does this. What is the term used to describe this
type of transport?
3. Compare passive transport to active transport.
4. Draw the structure of ATP? How is it related to active transport (what is the function
of ATP)? Explain why ATP has the ability to accelerate matter. Why do I usually refer to
ATP as a loaded gun? Does ATP have a high or low affinity for its third phosphate.
5. List the following in order from high to low affinity for phosphate: water, protein, ATP
6. After ATP has donated its phosphate to a protein or other substance, it becomes ADP.
If this happened without the reverse reaction, you would run out of ATP in seconds and
die. How does the cell, in very general terms, get that phosphate back on ADP to make
ATP again so that you can keep fueling your proteins?
7. What is the term we use to describe the addition of a phosphate onto a substance?
What about the removal of a phosphate from a substance?
8. New term I want you to know: KINASE. A kinase is obviously an enzyme (notice the
–ase ending) that adds phosphate to substances (catalyzes phosphorylation).
9. Be able to explain exactly what is happening in figure 5.18. Make sure you discuss
conformational changes and affinity for the phosphate. Explain why this allows
molecules to move from low to high concentration (against the concentration gradient).
STUDY WELL
“If you always put limit on everything you do, physical or anything else, it will
spread into your work and into your life. There are no limits. There are only
plateaus, and you must not stay there, you must go beyond them.”
-Bruce Lee
Life is just accelerating matter to your advantage.
-Dr. T.