1. Complete the following table to outline the structural differences between prokaryotic and eukaryotic cells.
Property Prokaryotes Eukaryotes
Nucleus
Cell size
Internal membranes
Cytoskeleton
Organization of DNA
Reproduction
2. Describe the basic composition of viruses. Are they considered to be living? Why/Why not?
3. A girl who consumes cyanide dies immediately because ATP production ceases. This medical problem involves the improper functioning of an organelle. Which organelle is affected? Is it underactive or overactive?
4. Draw a diagram of a phospholipid bilayer that indicates its overall structure and that includes the structures of the three types of proteins that are found in membranes. Discuss the mobility of lipids and proteins in the membrane.
5. For each of the following statements, indicate which of the following states applies. Note: Two of the statements have more than one correct answer.
D: simple diffusion
F: facilitated diffusion
A: active transport
N: none of the above
____ a. requires the presence of an integral membrane protein
____ b. involves proteins called ATPases
____ c. applies only to small, nonpolar solutes
____ d. applies only to ions
____ e. transport can occur in either direction across the membrane, depending on the prevailing concentration gradient
6. Describe how action potentials are propagated along a myelinated axon, and include a diagram to illustrate the mechanism. How does the process differ in unmyelinated axons?
7. Hypertension, or high blood pressure, is often treated with compounds called beta-blockers, which block -adrenergic receptors throughout the body. Why do you think beta-blockers are effective in reducing blood pressure?
8. Distinguish among the following processes: exocytosis, receptor-mediated endocytosis, and phagocytosis.
9. Outline the functions of the rough endoplasmic reticulum and the smooth endoplasmic reticulum. On which of the two are ribosomes present?
10. Distinguish between glycolysis and gluconeogenesis. How are these two pathways coordinately regulated? How does the concentration of ATP affect each pathway?
11. How is NAD+ regenerated through fermentation?
12. Define oxidative phosphorylation, and explain how the free energy of oxidation of NADH and FADH2 is used to synthesize ATP.
13. What are the light-dependent and light-independent reactions of photosynthesis? What is the function of chlorophyll, and what makes this pigment unique?
14. What are the substrates and products of the Calvin cycle?
15. Read the following article and answer the questions below. (2008). How cells clean house.
a. Define autophagy. What organelle carries out this function?
b. Describe a medical condition that results from the inability of cells to carry out autophagy.
c. Outline the process of autophagy in detail. You may use a diagram to illustrate what occurs.
d. Give an example of an organism that can exploit autophagy for its own survival, and explain how this is accomplished.
e. Explain the possible link between autophagy and lifespan.