3. Movement of integral membrane proteins between the apical and basolateral domains of an epithelial cell membrane is restricted by the presence of
(A) lipid rafts.
(B) basal lamina.
(C) desmosomes.
(D) tight junctions.
(E) gap juncitions.

74. In the cross Aa Bb CC Dd Ee × Aa Bb Cc Dd EE, in which all genes undergo independent assortment, what proportion of offspring are expected to be homozygous dominant for all five genes? (A) (1/4) (B) (1/4)2 (C) (1/4)3 (D) (1/4)4 (E) 0

75. In gymnosperms and angiosperms, which one is the correct description? (A) All gymnosperms are wind-pollinated. (B) The fossil record shows that angiosperms evolved directly from the Gnetophytes. (C) Horizontal gene transfer is restricted to prokaryotes and protists. (D) The fossil record shows that pollen cones of conifers have become increasingly complex through their evolutionary history. (E) Stamens and carpals are, in fact, modified sporangia-bearing leaves.

1. If the amount of enzyme in a reaction with an initial △G of -5 kcal/mole was doubled, what would the △G be? (A) -2.5 kcal/mole (B) -5 kcal/mole (C) -10 kcal/mole (D) +5 kcal/mole (E) +10 kcal/mole

2. Which is the most common route through which a protein is secreted from a eukaryotic cell? (A) plasmidplasma membranenuclear envelopesmooth endoplasmic reticulum (ER) (B) Golgi apparatuslysosomevesiclesplasma membrane (C) nuclear envelopevesiclesGolgi apparatusplasma membrane (D) rough endoplasmic reticulum Golgi apparatusvesicles plasma membrane (E) rough endoplasmic reticulumlysosomesvesiclescell membrane

4. Which of the following statements about feedback inhibition in metabolic pathways is most correct? (A) The product of the pathway inhibits its own production by competitively binding to reactants in the metabolic pathway. (B) The product of the pathway inhibits its own production by noncompetitively binding to reactants in the metabolic pathway. (C) The product of the pathway inhibits its own production by competitively inhibiting the binding of a substrate to the active site of an enzyme within the metabolic pathway. (D) The product of the pathway inhibits its own production by noncompetitively inhibiting the binding of a substrate to the active site of an enzyme within the metabolic pathway. (E) All of the above

5. Which is NOT a microtubule-organizing center (MTOC)? (A) centrosome (B) basal body of cilia (C) mitotic spindle pole (D) kinetochore (E) all of the above

6. An mRNA sequence is 5’-AUG-GGC-ACU-CAU-ACU-UAA-3’, where AUG is the start codon and UAA is the stop codon. How many distinct aminoacyl-tRNA synthetases are required to translate the mRNA sequence? (A) 2 (B) 3 (C) 4 (D) 5 (E) 6

7. Self-splicing of group II introns is similar to nuclear pre-mRNA splicing because (A) both need snRNPs. (B) both need guanosine. (C) both need ATP. (D) both form lariat structure. (E) both form spliceosome.

8. Assuming a fat molecule can be oxidized into 2 glycerol molecules, which are then converted to glyceraldehyde-3-phosphate in intermediate glycolysis, how many ATP can be produced from a fat molecule? (A) 4 (B) 8 (C) 24 (D) 36 (E) 48

9. Which of the following proteins is NOT a component of focal adhesions? (A) cadherins (B) integrins (C) actin filaments (D) linker protein (E) fibronectin/collagen