Download Where is DNA in a euk cell?

Biol 211G, Cellular and Organismal Biology
Extra Practice & Review: Cell Overview & Enzymes
Don’t forget to add the section on Exergonic and Endergonic reactions (pages 120-121) to your
after-lecture readings for this topic. As usual, let lecture be your guide to the readings. We
don’t always cover everything in the readings, so use lecture to help you focus in on the most
relevant sections/information in the readings.
1. Don’t forget to go back and review your prep assignment questions as part of your review!
2. What type of cell do we have?
3. What is a characteristic feature of all eukaryotic cells?
4. What surrounds every cell?
5. What do ribosomes do?
6. What are most enzymes made of?
7. What do enzymes do to reaction rates? Are enzymes “recyclable”, or are they only
“consumed”?
8. Be sure you know what the following terms mean, and how they relate to one another:
-anabolic
-catabolic
-endergonic
-exergonic
-hydrolysis
-dehydration
9. What is the activation energy of a reaction, and what do enzymes do to the activation
energy?
10. If an enzyme is catalyzing an exergonic reaction, what will the enzyme do to each of the
following?
a. the initial energy of the reactants
b. the initial energy of the products
c. the activation energy of the reaction
d. the energy difference between the reactants and products
11. What kinds of things happen in the active site of an enzyme that contribute to speeding up
the reaction?
12. Compare and contrast competitive and non-competitive enzyme inhibitors. Which one looks
like the substrate of the enzyme?
13. We said that solutions of “non-optimal” pH can influence reaction rates of enzyme-catalyzed
reactions….
a. what is pH?
b. which solution is more acidic- pH 2 or pH 9?
c. which solution has a higher concentration of hydrogen ions: pH 2 or pH 9?
d. why does pH influence reaction rates of enzyme-catalyzed reactions?
14. Why does pepsin (a protein-digesting enzyme in the stomach) need to have a different pH
optimum than chymotrypsin (a protein-digesting enzyme in the small intestine)? What would
happen to protein digestion rates in the stomach if pepsin was shifted to a pH of 6?
15. Why can you “cook” seafood with both heat and acid?
Clicker Questions
Where is DNA in a euk cell?
A. nucleus
B. cell membrane
C. floating around in cytoplasm
D. euk cells don’t have DNA
Plant cell wall is made of
A. starch
B. glycogen
C. cellulose
D. hemoglobin
E. glucose
Which is made up of
A. amino acids
B. fatty acids
C. glycogen
D. glucose
E. starch
Which is responsible for protein synthesis?
A. microtubules
B. microfilaments
C. nucleus
D. ribosomes
Protein synthesis: Adding amino acids & forming peptide bonds
Which level of protein structure is being assembled?
A. primary
B. secondary
C. tertiary
D. quaternary
Microtubules and Microfilaments
What do they have in common?
A. components of the cytoskeleton
B. made of tubulin
C. only found in plant cells
D. only found in bacterial cells
Breaking down proteins into amino acids
a. hydrolysis
b. condensation
The reaction catalyzed by sucrase:
a. catabolic
b. anabolic
The reaction catalyzed by sucrase:
a. endergonic
b. exergonic
Figure 6.12: the reaction shown is
a. endergonic
b. exergonic
c. fascinating
*this one was more challenging in class today, so be sure you can explain the answer
What level of protein structure is lost with denaturation?
a. primary
b. secondary
c. tertiary
d. all of the above
e. b & c