Quiz 6

e

Microfilaments are well known for their role in which of the following? a. ameboid movement b. formation of cleavage furrows c. contracting of muscle cells d. ameboid movement and formation of cleavage furrows e. ameboid movement, formation of cleavage furrows, and contracting of muscle cells

light microscope, specimen is alive

A researcher wants to film the movement of chromosomes during cell division. Which type of microscope should he choose and why is it the best choice? a. scanning electron microscope, because of its ability to visualize the surface of subcellular objects. b. light microscope, because of its high resolving power c. transmission electron microscope, because of its high resolving power d. transmission electron microscope, because of its high magnifying power e. light microscope, because the specimen is alive

in bacterial cells

Chloroplasts and mitochondria are thought to be of prokaryotic origin. One piece of evidence that supports this hypothesis is that these organelles contain prokaryotic-like ribosomes. These ribosomes are probably most similar to ribosomes found ______. a. free in the cytoplasm of eukaryotes b. on the rough ER c. in bacterial cells d. The first two answers are correct. e. The first three answers are correct.

a

Consider a protein that is made in the rough endoplasmic reticulum. You observe that when the synthesis of the protein is completed, the protein is located in the ER membrane. Where else in the cell might this protein be found? a. embedded in the plasma membrane functioning in the transport of molecules into the cell b. in the aqueous interior of a lysosome functioning as a digestive enzyme c. in the internal space of the Golgi apparatus, being modified before the protein is excreted d. in the cytoplasm, functioning as an enzyme in carbohydrate synthesis e. in a mitochondrion functioning in ATP synthesis

plasmodesmata

Dye injected into a plant cell might be able to enter an adjacent cell through _____. a. a microtubule b. a cell wall c. plasmodesmata d. a tight junction e. a gap junction

lysosome

In animal cells, hydrolytic enzymes are packaged to prevent general destruction of cellular components. Which of the following organelles functions in this compartmentalization? a. chloroplast b. lysosome c. central vacuole d. peroxisome e. glyoxysome

b

In terms of cellular function, what is the most important difference between prokaryotic and eukaryotic cells? a. Only eukaryotic cells have DNA. b. Compartmentalization of the cytoplasm by membrane-bounded organelles only occurs in eukaryotic cells. c. Eukaryotic cells have a plasma membrane and prokaryotic cells do not. d. Eukaryotic cells are larger than prokaryotic cells. e. Only eukaryotic cells can synthesize proteins but prokaryotic cells cannot.

cytoskeletons

Motor proteins provide for molecular motion in cells by interacting with what types of cellular structures? a. sites of energy production in cellular respiration b. membrane proteins c. ribosomes d. cytoskeletons e. cellulose fibers in the cell wall

e

The Golgi apparatus has a polarity or sidedness to its structure and function. Which of the following statements correctly describes this polarity? a. Transport vesicles fuse with one side of the Golgi and leave from the opposite side. b. Proteins in the membrane of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. c. Lipids in the membrane of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. d. Soluble proteins in the cisternae (interior) of the Golgi may be sorted and modified as they move from one side of the Golgi to the other. e. All of these correctly describe polar characteristics of the Golgi function.

c

The average wavelength of visible light is about 550 nanometers (or 0.5 micrometers). Which of the following cellular structures is unlikely to be resolved with a light microscope? a. a typical eukaryotic cell, which is between 10 and 100 micrometers in diameter b. a typical bacterial cell, which is between 0.5 and 2.0 micrometers in diameter c. nuclear pore complexes (100 nanometers in diameter) on the nuclear membrane d. chromosomes in the nucleus during cell division e. the nucleus, which is typically about 5 micrometers in diameter

d

The cell walls of bacteria, fungi, and plant cells and the extracellular matrix of animal cells are all external to the plasma membrane. Which of the following is a characteristic of all of these extracellular structures? a. They must block water and small molecules in order to regulate the exchange of matter and energy with their environment. b. They must permit information transfer between the cell's cytoplasm and the nucleus. c. They must provide a rigid structure that maintains an appropriate ratio of cell surface area to volume. d. They are constructed of materials that are largely synthesized in the cytoplasm and then transported out of the cell. e. They are composed of a mixture of lipids and carbohydrates.

cytoskeleton

Where would you expect to find proteins involved with movement of structures within a cell? a. ribosomes b. transport vesicles moving from the ER to the Golgi c. plasma membrane d. muscles e. cytoskeleton

d

Which of the following are likely to limit the maximum size of a cell? a. the shape of the cell b. the cell's surface-to-volume ratio c. the time it takes a molecule to diffuse across a cell d. All of the choices are correct. e. None of the choices are correct.

peroxisome

Which of the following contains enzymes that transfer hydrogen from various substrates to oxygen? a. lysosome b. vacuole c. mitochondrion d. Golgi apparatus e. peroxisome

mitochondrial outer membrane

Which one of the following five membranes is most likely to have a lipid composition that is distinct from the other four? a. Golgi apparatus b. endoplasmic reticulum c. plasma membrane d. lysosome membrane e. mitochondrial outer membrane

free cytoplasmic ribosomes

Which one of the following organelles is unlikely to show enhanced abundance in the pancreatic cells that secrete large amounts of digestive enzymes? a. transport vesicles b. Golgi apparatus c. free cytoplasmic ribosomes d. rough endoplasmic reticulum e. All of the above will increase in pancreatic cells secreting digestive enzymes