MasteringBiology Chapter 6: A Tour of the Cell

A protein that ultimately functions in the plasma membrane of a cell is most likely to have been synthesized __________. A) in the rough endoplasmic reticulum B) in the ribosomes of the mitochondria C) on free cytoplasmic ribosomes D) in the smooth endoplasmic reticulum E) in the plasma membrane

A

The endoplasmic reticulum is part of the endomembrane system, which also includes the __________. A) nuclear envelope, the Golgi apparatus, lysosomes, and vesicles B) mitochondria, the Golgi apparatus, lysosomes, and vesicles C) nuclear envelope, the Golgi apparatus, and mitochondria D) nuclear envelope, the Golgi apparatus, mitochondria, and chloroplasts E) nuclear envelope, the Golgi apparatus, and ribosomes

A

The endosymbiont theory explains the origins of __________. A) mitochondria and chloroplasts B) chloroplasts and the plant cell vacuole C) the Golgi apparatus and mitochondria D) mitochondria and ribosomes E) There is no correct answer because the endosymbiotic theory is no longer supported.

A

The function of the rough endoplasmic reticulum (RER) is __________. A) to synthesize proteins that are secreted as glycoproteins B) to synthesize lipids C) to detox drugs and alcohol D) to synthesize sex hormones E) to store calcium ions

A

Which of the following is present in a prokaryotic cell? A) Ribosomes B) Mitochondrion C) Nuclear envelope D) Chloroplast E) ER

A

Which statement about the cytoskeleton is true? A) Components of the cytoskeleton often mediate the movement of organelles within the cytoplasm. B) Intermediate filaments are hollow tubes of protein that provide structural support. C) Microtubules are chains of proteins that resist stretching. D) Microfilaments are more permanent structures in cells compared to intermediate filaments and microtubules. E) Plant cells lack a cytoskeleton because they have a rigid cell wall.

A

A substance moving from outside the cell into the cytoplasm must pass through __________. A) a microtubule B) the plasma membrane C) the endomembrane system D) a ribosome E) the nucleus

B

Cell motility, which includes changes both in cell location and in the movement of cell parts, requires interactions of the cytoskeleton __________. A) with "feet" to "walk" B) with motor proteins C) with glycosomes D) without ATP E) with the endoplasmic reticulum

B

Cilia and flagella move due to the interaction of the cytoskeleton with which of the following? A) Actin B) Motor proteins C) Pseudopodia D) Mitochondria E) Tubulin

B

The network of fibers that organizes structures and activities in a cell __________. A) are microtubules B) is the cytoskeleton C) are microfilaments D) are intermediate filaments E) are centrioles

B

The organelle that is a plant cell's compartment for the storage of inorganic ions such as potassium and chloride is the __________. A) food vacuole B) central vacuole C) contractile vacuole D) lysosome E) plastid

B

The region of a bacterial cell that contains the genetic material is called the __________. A) nucleus B) nucleoid C) nucleolus D) nucleosome E) capsule

B

Animal cells have unique organelles called __________ that are composed of structures called __________. A) centrioles; centrosomes B) centromeres; centrioles C) centrosomes; centrioles D) nucleosomes; centrioles E) centrosomes; nucleosomes

C

Cells are small because __________. A) small cells are easier to back together B) smaller objects have a smaller ratio of surface to volume C) of the geometric relationships between surface and volume D) area is proportional to a dimension cubed (X3), whereas volume is proportional to a dimension squared (X2) E) None of the listed responses is correct.

C

In terms of cellular function, what is the most important difference between prokaryotic and eukaryotic cells? A) Eukaryotic cells can synthesize proteins but prokaryotic cells cannot. B) Eukaryotic cells are much more successful than prokaryotic cells. C) Eukaryotic cells are compartmentalized, which allows for specialization. D) Eukaryotic cells lack many of the organelles found in prokaryotes. E) Eukaryotic cells are larger than prokaryotic cells.

C

What is the functional connection between the nucleolus, nuclear pores, and the nuclear membrane? A) The nuclear pores are connections between the nuclear membrane and the endoplasmic reticulum that permit ribosomes to assemble on the surface of the ER. B) The nucleolus contains messenger RNA (mRNA), which crosses the nuclear envelope through the nuclear pores. C) Subunits of ribosomes are assembled in the nucleolus and pass through the nuclear membrane via the nuclear pores. D) Endoplasmic reticulum membrane is produced in the nucleolus and leaves the nucleus through the nuclear pores.

C

Which of the following is false in respect to cells' chromosomes? A) Chromosomes contain DNA and proteins. B) Chromosomes are present throughout a cell's reproductive cycle. C) Chromosomes are only visible as a cell is about to divide. D) Chromosomes exist even when cells are not actively synthesizing proteins.

C

You would expect a cell with an extensive Golgi apparatus to __________. A) make a lot of ATP B) move rapidly C) secrete a lot of protein D) absorb nutrients in the GI tract E) store large quantities of ions

C

Bacterial cells are prokaryotic. Unlike a typical eukaryotic cell they __________. A) lack chromosomes B) have a smaller nucleus C) lack a plasma membrane E) have no ribosomes

D

Basal bodies are most closely associated with which of the following cell components? A) Nucleus B) Mitochondria C) The central vacuole D) Cilia E) Golgi apparatus

D

Dye injected into a plant cell might be able to enter an adjacent cell through __________. A) a tight junction B) a microtubule C) a cell wall D) plasmodesmata E) a gap junction

D

Evidence that supports the prokaryotic origins of mitochondria and chloroplasts are all of the following except __________. A) that the ancestral prokaryote had two outer membranes, which became the double membranes of the mitochondria and chloroplasts B) that mitochondria and chloroplasts have multiple copies of linear DNA molecules associated with their inner membranes C) that mitochondria and chloroplasts can grow and reproduce within a cell D) that mitochondria and chloroplasts have multiple copies of circular DNA molecules associated with their membranes E) that mitochondria and chloroplasts are somewhat independent within a cell

D

Observing a fluorescent micrograph cell with intermediate filaments would help you identify the cell as a __________. A) prokaryotic cell B) eukaryotic cell C) plant cell D) human skin cell E) fungal cell

D

The extracellular matrix of the animal cell has all of the following molecular components except __________. A) collagen B) proteoglycans C) fibronectin D) a middle lamella E) integrins

D

Cell junctions in plant cells are called __________, and communicating junctions in animal cells are called __________. A) tight junctions; gap junctions B) desmosomes; plasmodesmata C) plasmodesmata; tight junctions D) gap junctions; plasmodesmata E) plasmodesmata; gap junctions

E

Microfilaments function in cell motility including __________. A) muscle contraction, amoeboid movement, and flagella motion B) muscle contraction, amoeboid movement, and cilia motion C) muscle contraction, amoeboid movement, and centriole function D) flagella motion, cilia motion, and centriole function E) muscle contraction, amoeboid movement, and cytoplasmic streaming in plants

E

The walls of plant cells are largely composed of polysaccharides and proteins that are synthesized __________. A) externally to the plasma membrane B) in the smooth endoplasmic reticulum C) in the Golgi apparatus D) in the rough endoplasmic reticulum E) in the rough endoplasmic reticulum and in the Golgi apparatus

E

Which of the following groups is primarily involved in synthesizing molecules needed by the cell? A) Lysosome, vacuole, and ribosomes B) Vacuole, rough endoplasmic reticulum, and smooth endoplasmic reticulum C) Smooth endoplasmic reticulum, ribosomes, and vacuole D) Rough endoplasmic reticulum, lysosome, and vacuole E) Ribosomes, rough endoplasmic reticulum, and smooth endoplasmic reticulum

E

Your intestine is lined with individual cells. No fluids leak between these cells from the gut into your body. Why? A) The intestinal cells are fused together into one giant cell. B) The intestinal cells are bound together by plasmodesmata. C) The intestinal cells are bound together by gap junctions. D) The intestinal cells are bound together by the extracellular matrix. E) The intestinal cells are bound together by tight junctions.

E

__________ are membrane-bound metabolic compartments that specialize in the production of hydrogen peroxide (H2O2) and its conversion to water. A) Lysosomes B) Ribosomes C) Centrosomes D) Nucleosomes E) Peroxisomes

E