22. Which electron carrier(s) function in the citric acid cycle?
(A) NAD+ only
(B) ADP and ATP
(C)  the electron transport chain
(D) NADH and FADH2
(E) Glucose

18._________is a regulatory mechanism in which the end product of a metabolic pathway inhibits an enzyme that catalyzes an early step in the pathway. (A) Allosteric inhibition (B) Cooperative inhibition (C) Feedback inhibition (D) Metabolic inhibition (E) Competitive inhibition

19.Which of the following is the most common pathway taken by a newly synthesized protein that will be secreted by a cell? (A) rough ER→ Golgi → transport vesicle →  nucleus (B) Golgi→  rough ER lysosome →  transport vesicle →  plasma membrane (C) rough ER → lysosome →  transport vesicle →  plasma membrane (D) rough ER →  Golgi → transport vesicle→  plasma membrane (E) nucleus → endosome →  Golgi →  transport vesicle→  plasma membrane

20. In some cells, there are many ion electrochemical gradients across the plasma membrane even though there are usually only one or two proton pumps present in the membrane. The gradients of the other ions are most likely accounted for by ________.(A) osmosis (B)ion channels (C) pores in the plasma membrane (D) passive diffusion across the plasma membrane (E) cotransport proteins

21. One of the major categories of receptors in the plasma membrane functions by forming dimers, adding phosphate groups, and then activating relay proteins. Which type does this? (A) G protein-coupled receptors (B) receptor tyrosine kinases (C) steroid receptors (D) ligand-gated ion channels (E) glycolipid

23. Which of the following sequences correctly represents the flow of electrons during photosynthesis? (A) NADPH →O2 →CO2 (B) NADPH→ chlorophyll→ Calvin cycle (C) H2O→ NADPH → Calvin cycle (D) NADPH→ electron transport chain→ O2 (E) Pyruvate → ATP Calvin cycle

24. At the M phase checkpoint, the complex allows for what to occur? (A) Separase enzyme cleaves cohesins and allows chromatids to separate (B) Cohesins alter separase to allow chromatids to separate (C) Daughter cells are allowed to pass into G (D) All microtubules are made to bind to kinetochores (E) Kinetochores are able to bind to spindle microtubules

25. Which of the following is correctly paired? (A) forebrain -cerebral cortex (B)midbrain - hypothalamus (C)hindbrain - thalamus (D) diencephalon -medulla oblongata

26. Which one serves as the gateway to the cortex for the sensory systems. (A) Basal Nuclei (B) Amygdala (C) Thalamus (D) Corpus Callosum

27. Which of the following actions is controlled by the parasympathetic nervous system? (A) Constricts pupil of eye (B) Inhibits activity of stomach and intestines (C) Accelerates heart (D) Stimulates adrenal medulla

28. What enhances the neural signal conduction speed along the axon in central nervous system? (A) Oligodendrocytes (B) Schwann Cell (C) Microglia (D) Astrocyte