a. It has a high demand for energy. b. It has a low demand for energy.

1. What does the presence of many mitochondria imply about a cell’s energy requirements? a. It has a high demand for energy. b. It has a low demand for energy. c. There is a fluctuation in the energy needs, so flexibility is required. d. The number of mitochondria provides no implication of energy needs.

2. Cells lining the small intestine have numerous fingerlike projections on their free surface that contain microvilli. What is the function of microvilli? a. to move substances across the cell’s surface b. to increase the cell’s surface area and absorptive ability c. to decrease the cell’s surface area and control filtration d. to move substances across the cell’s surface

3. Which statement correctly distinguishes between cytoplasm and cytosol? a. Cytosol has a higher concentration of suspended proteins than cytoplasm. b. Cytosol is the intracellular fluid and is composed of nutrients, ions, proteins, and wastes, and cytoplasm is the term for all material located between the cell membrane and nucleus. c. Potassium ion concentration is higher in cytoplasm than in cytosol. d. Cytosol and cytoplasm refer to the same substance.

4. Which component of the cell membrane is primarily responsible for the membrane’s ability to form a physical barrier between the cell’s internal and external environments? a. phospholipid bilayer b. glycocalyx c. peripheral proteins d. proteoglycans

5. What term below describes the cell membrane? a. semipermeable b. freely permeable c. impermeable d. nonpermeable

6. Some pediatricians recommend the use of a 10% salt solution to relieve congestion for infants with stuffy noses. What effect would such a solution have on the cells lining the nasal cavity, and why? a. Cells will lose water because this is a hypertonic solution. b. Cells will lose water because this is a hypotonic solution. c. Cells will gain water because this is a hypertonic solution. d. Cells will gain water because this is a hypotonic solution.

7. During DNA replication, a nucleotide is deleted from a sequence that normally codes for a polypeptide. What effect will this deletion have on the amino acid sequence of the polypeptide? a. No effect, deletion will be skipped. b. No effect, deletion will be automatically repaired. c. Amino acid sequence will disintegrate. d. Amino acid sequence would be altered.

8. When they encounter bacteria, certain types of white blood cells engulf the bacteria and bring them into the cell. What is this process called? a. pseudocytosis b. exocytosis c. pinocytosis d. phagocytosis

9. What process would be affected by the lack of the enzyme RNA polymerase? a. Nothing would be affected; DNA polymerase would take over. b. It would affect the cell’s ability to duplicate DNA. c. It would affect the cell’s ability to translate DNA. d. It would affect the cell’s ability to transcribe DNA.

10. What are two reasons that mRNA transcription is so vital? a. Protein synthesis occurs through transcription, and it occurs in the nucleus to maintain homeostasis. b. DNA cannot leave the nucleus, and transcription ensures that mRNA exactly matches the coding strand of the gene. c. It allows formation of chains of amino acids, and the same information is presented in a different language. d. None of these answers are correct.