8. The evolution of complex multicellularity in eukaryotes
(A) occurred only once, in the common ancestor of all eukaryotes.
(B) occurred only once, in the common ancestor of all multicellular eukaryotes.
(C) occurred only once, in the animal lineage.
(D) occurred independently in several eukaryotic lineages.
(E) no evidence to support any of above statements.

4. A competitive inhibitor in an enzymatic reaction (A) mimic the normal substrate (B) binds to the enzyme away from the active site (C) cannot bind to the active site of the enzyme (D) alters the shape of the enzyme making binding of the normal substrate impossible (E) both B and D are correct.

5. Cell signaling is of the paracrine type when (A) Immune cells secrete proteins which stimulates themselves to be activated. (B) endocrine cells secrete hormones (C) signaling cells secrete a regulator acting on a distant cell (D) signaling cells secrete a regulator acting on a nearby cell (E) none of above

6. What is an incorrect statement about brown fat? (A) It generates heat in hibemating animals (B) It generates heat from store fats without ATP production (C) It is made up cells packed with mitochondria (D) It is found in human body (E) It does not generate heat in human

7. Plastids that are surrounded by more than two membranes are evidence of (A) evolution from mitochondria (B) fusion of plastids (C) origin of the plastids from archaea (D) secondary endosymbiosis (E) all of above

9. Among the organisms listed here, which are thought to be the closest relatives of fungi? (A) slime molds (B) vascular plants (C) animals (D) mosses (E) archaea

10. The innermost layer of the root cortex is the (A) Core (B) pericycle (C) endodermis (D) pith (E) epidermis

11. Compared with a cell with few aquaporin proteins in its membrane, a cell containing many aquaporin proteins will have a (A) faster rate of osmosis (B) lower water potential (C) higher water potential (D) faster rate of active transport (E) both A and B are correct

12. A seed develops from an (A) ovum (B) embryo (C) ovule (D) ovary (E) oviduct

13. If a long-day plant has a critical night length of 9 hours, which 24-hour cycle would prevent flowering? (A) 16 hours light/8 hours dark (B) 14 hours light/10 hours dark (C) 4 hours light/8 hours dark/4 hours light/8 hours dark (D) 8 hours light/8 hours dark/light flash/8 hours dark (E) all of above are flowering

14. Many endotherms use a countercurrent exchange system to conserve heat. How does this function? (A) Heat is transferred from arteries to veins against a thermal gradient. (B) Heat is transferred from veins to arteries against a thermal gradient. (C) Heat is transferred from arteries to veins along a thermal gradient. (D) Heat is transferred from veins to arteries along a thermal gradient. (E) Heat is transferred either from-veins-to-arteries or from-arteries-to-veins, as long as it is along a thermal gradient.