61) The nuclear envelope is continuous with the rough ER, but it differs from the rough ER in that it
A) is not associated with ribosomes.
B) has unique pores.
C) consists of two membranes separated by a space.
D) consists of tubes, like the smooth ER.
62) Membrane-bound organelles have the same type of membrane as the plasma membrane
except
A) for the absence of a glycocalyx.
B) for the absence of cholesterol.
C) the nonpolar tails face outward.
D) they are all covered with ribosomes.
63) In the process of phagocytosis, the organelles whose enzymes break down ingested foreign cells are the
A) nucleoli.
B) smooth endoplasmic reticulum.
C) peroxisomes.
D) lysosomes.
64) During mitosis, the kinetochore microtubules of the mitotic spindle
A) attach to chromatids and align them at the metaphase plate.
B) push on the chromatids.
C) anchor the centriole to the cell membrane.
D) push the two poles of the cell apart.
65) The theory proposing that aging results from the effects of free radicals is primarily a theory of
A) wear and tear.
B) genetically programmed aging.
C) progressive disorder of immunity.
D) cross-linking of glucose.
66) The cytoskeletal elements that are analogous to the muscles of the body which generate pseudopodia and contractile forces in conjunction with myosin are
A) microtubules.
B) microfilaments.
C) intermediate filaments.
D) integral proteins.
67) Transcription of DNA requires the presence of
A) centrosomes.
B) extended chromatin.
C) histones.
D) nucleosomes.
68) The process of cellular aging may involve all of the following
except
A) accumulated damage by free radicals.
B) decreased production of lysosomes.
C) excessive metabolic rate.
D) progressive shortening of telomeres.
69) During what phase of mitosis does the mitotic spindle break down and disappear?
A) metaphase
B) anaphase
C) telophase
D) late prophase
70) The cytoskeletal elements that form a ring to "squeeze" the two daughter cells apart during cytokinesis are
A) microtubules.
B) microfilaments.
C) intermediate filaments.
D) the microtrabecular lattice.
71) During what phase of the cell cycle is the DNA duplicated?
A) metaphase
B) anaphase
C) interphase
D) prophase
72) The plasma membrane is
A) a single-layered membrane that surrounds the nucleus of the cell.
B) a single-layered membrane enclosing the plasma.
C) the membrane surrounding the cell.
D) a membrane composed of tiny shelves or cristae.
73) The cell that gathers information and controls body functions is a
A) macrophage.
B) fat cell.
C) sperm cell.
D) neuron.
74) The temporary structures in the cytoplasm include all of the following
except
A) pigments.
B) glycosomes.
C) lipid droplets.
D) the Golgi apparatus.
75) Which of the following is an inclusion,
not
an organelle?
A) lysosome
B) microtubule
C) mitochondrion
D) glycosome