A person who holds his breath retains excess CO
. This results in an elevated blood pH.
A solution with pH 6.0 is more acidic than one with pH 7.4.
A one molar solution of CaCl
has the same number of osmotically active solute molecules as a 3
molar solution of glucose.
A. are hydrophobic molecules
B. can be used in the body for insulation and energy storage.
C. are formed by dehydration synthesis
D. all of the above
E. none of the above
9. Hydrogen bonds
A. determine the pH of solutions
B. bind different portions of proteins into the secondary structure
C. are important determinants of the double helix structure of DNA
D. B and C are correct, but not A.
E. A, B and C are all correct.
10. If four bases in a DNA strand are A, G, C, T, the complementary bases in the opposite strand of
____, while the complementary bases on an
strand will be ____.
A. A, G, C, T and U, G, C, A
B. U, C, G, A and T, C, G, A
C. T, C, G, A and U, C, G, A
D. A, G, C, T and U, C, G, A
Organelles + Protein Synthesis
Membrane lipids and cholesterol are held in place by cytoskeletal proteins like actin.
12. The listed events all occur during the synthesis of proteins for export. List them in the proper order:
Protein folds in the ER
ii. mRNA synthesized
iii. DNA unwinds
iv. tRNA binds to mRNA
A. i > ii > iii > iv
B. ii > i > iii > iv
C. iii > ii > i > iv
D. iii > ii > iv > i
13. T-F? A gene with 3600 bases will encode a protein with 10800 amino acids.
14. T-F? Humans have more than 250,000 genes encoded in their DNA.
15. T-F? Cell membranes are 100 nm (100x10
m) thick; mitochondria are 10
m) long; and
intestinal epithelial cells are 100
m) in diameter.