Unit 4 Exam Study Guide
Cell Communication
1. What type of molecules can pass through the cell membrane without proteins? Examples?
2. What type of molecules need proteins to pass through the cell membrane? Examples?
3. Paracrine Signaling
a. What is it?
b. Short or Long Responses?
c. Near or Far distance?
d. Typical ligands used?
e. What is this useful for?
4. Synaptic/Neuronal Signaling
a. What is it?
b. Short or Long Responses?
c. Near or Far Distance?
d. Typical Ligands?
e. What is it useful for?
5. Endocrine Signaling
a. What is it?
b. Short or Long Responses?
c. Near or Far Distance?
d. Typical Ligands?
e. What is it useful for?
6. How does epinephrine lead to different effects in different parts of the body (ie: Blood vessel
constriction in the gut, and blood vessel dilation in the skeletal muscle)?
7. When is Insulin released? Glucagon?
8. Explain the phenomenon of Quorum Sensing.
9. What are the 3 stages of cell signaling?
10. What type of molecules can pass through the plasma membrane and bind to intracellular
receptors?
a. Give 3 examples of specific hormones
11. What type of molecules can not pass through the plasma membrane and need to bind to
extracellular receptors?
a. Give 3 examples of specific hormones
12. What is the purpose of the signal transduction phase of cell signaling?
13. Explain (in depth) how G-protein-coupled receptors work, including the reception, transduction,
and response stages.
14. What enzyme class is responsible for phosphorylating proteins within the signal transduction
pathway?
15. What enzyme class is responsible for deactivating proteins via dephosphorylation?
16. Explain (in depth) how tyrosine kinase receptors work, including the reception, transduction,
and response stages.
17. Explain (in depth) how Ligand gated/ion-channel receptors work, including the reception,
transduction, and response stages.
18. Explain how the secretion of insulin and glucagon utilizes negative feedback to maintain
homeostasis.
19. Explain the role oxytocin plays in two important positive feedback loops
a. Contractions
b. Lactation
The Cell Cycle
1. What phase of the cell cycle does a cell spend most of its time in?
2. What are the 3 stages of Interphase and what happens at each?
a.
b.
c.
3. What are the 3 checkpoints of the cell cycle and what is checked for at each?
a.
b.
c.
4. What happens when p53 is mutated and rendered ineffective?
5. What is the normal cell death process known as?
6. Explain how cyclins interact with cyclin-dependent kinases to progress the cell through the cell
cycle.
7. What is the end goal of mitosis? (Focus on diploid vs. haploid)
8. What is happening at each stage of Mitosis?
a. Prophase
b. Prometaphase
c. Metaphase
d. Anaphase
e. Telophase
f. Cytokinesis
9. How do prokaryotic cells divide? What is this process called?
10. How does cancer arise?
Meiosis
1.
2.
3.
4.
5.
6.
Why is Meiosis known as a reduction division process?
Why is it important for gametes to be haploid?
Which phase of Meiosis reduces the number of chromosomes from diploid to haploid?
Which phase of Meiosis produces 4 unique haploid daughter cells?
What is a homologous chromosome?
How is it possible that two people could have two children with entirely different traits? What
key processes are responsible for this?
7. Name the key differences between Mitosis and Meiosis.