Download Sample exam 2

Chemistry 256
Sample exam 2
1. What molecules could be considered storage for amino acids.
a.
b.
c.
d.
e.
Carbohydrate
Glycogen
Proteins
Triacylglyderides
Urea
2. What is the fate of the amino group when amino acids are degraded and excreted
from the body.
3. What is the product of a hydrolysis of a protein
4. Which enzyme can hydrolyze proteins?
a. Aminotransferease
b. Lysosome
c. Protease
d. ATPase
e. Dehydrogenase
f.
5. In what process is ubiquitin used? Breifly describe it action.
6. What are the fates of amino acids that has been degraded?
a.
b.
c.
d.
e.
The NH3 group is converted to Urea
The NH3 group is converted to Acetyl-CoA
The carbon skeleton is converted to Glucose
The carbon skeleton is converted to Urea
The carbon skeleton is converted to Ketone bodies
7. What are the products of the reaction below (transamination)
NH3+
-
O-
CO2-
O2C
aminotransferase
+
CH3
O
O
8 What process if the PLP enzyme important. Describe its action
9. a. What are major components of light harvesting antenna?
a.
b.
c.
d.
e.
Chlorophyll
Carotene
Protein
THF
Urea
b. What is the main functionality/functional group of the compounds you choose above
that gives rise to their ability to harvest light.
10. During Photosynthesis what event occurs in the OEC? What does it stand for?
11. Which part of the chloroplast do the ‘light reactions’ take place?
a.
b.
c.
d.
e.
Outer membrane
Stroma
Thylakoid membrane
Inner membrane
Chloroplast center
12. Which photosynthetic reaction center (PSI or PSII) is responsible for
ATP synthesis_________________
NADPH synthesis______________
O2 production.________________
Proton gradient formation________
13. Which Plastoquinone(ol) shown below is oxidized and which is reduced.
14. Which events take place in the stroma of the chloroplast?
a.
b.
c.
d.
ATP synthesis,
OEC
Reduction of NADP
Formation of oxygen
15 a. What is photophosphorlation?
b. Where does it occur?
c. What other process from chem 255 does this mimic?
16. What is the important product of the Calvin cycle that goes on to produce
carbohydrates?
17. What 2 reactants do photosystem I and II contribute to the Calvin cycle?
18. Circle what is true regarding the Calvin Cycle
Carbon dioxide is fixed
GAP is formed
Nitrogen is fixed.
Acetyl CoA is formed.
ADP is produced
19. What compound below is Chlorophyll similar to?
Hemoglobin
Glucose
ATP
AcCoA
Mitochondria
20. When Nitrogen is ‘Fixed’ what is occurring:
a.
b.
c.
d.
e.
Nitrogen is being oxidized to a biologically useful form
Nitrogen is being reduced to a biologically useful form
Nitrogen from amino acids is being converted to a biologically useful form
Nitrogen is being decomposed and excreted to the soil.
Nitrogen is being assimilated into Urea.
21. What type of plants fix nitrogen?
22. Is the fixing of nitrogen an exothermic or endothermic process?
23. Which molecule is necessary for the assimilation of nitrogen into amino acids?
a.
b.
c.
d.
Acetyl Co-A
Pyruvate
-Ketoglutarate
GAP
24 Which Amino acids would you consider to be both Glucogenic and Ketogenic (use
chart below)?
25. The biosynthesis of Tyrosine depends upon the hydroxylation of phenylalanine by
the enzyme phenylalanine dehydrogenase (PAH) (show below).
a. What disease results from the lack of PAH?
b. Show the reaction that will occur when phenylalanine cannot be converted to
tyrosine.
26. Depict the hydrogen bonding between the base pair Cand G.
O
H
H N
N
N
H
N
HN
NH
N
O
NH2
Guanine
27 Depict the enol form of Guanine base
cytosine
H
28. Describe ‘translation’
H
O
N
N
N
H
N
NH
HN
N
O
adenine
thymine
29. Describe transcription.
30. Fill in the missing reactant and product of the transamination reaction below.
O
-
Reactant
+
CO2-
O2C
aminotransferase
OCH3
O
+ Product
O
b. The PLP is an important cofactor in the reaction above. Circle the compound below
that is PLP.
H
H
O
O-
PO
O
CH3
H
O
O-
PO
N
H
CH3
PO
H
O
OCH3
CH2
O-
PO
N
H
CH3
31. (6 pts) With the information below draw a RNA trinucleotide of A T C going from
5’3’