- Chapter 6-A Tour of the Cell
1) The smallest cell structure that would most likely be visible with a standard (not super- resolution) research-grade light microscope is a ____.
A) mitochondrion
B) microtubule
C) ribosome
D) microfilament
Answer: A
2) The advantage of light microscopy over electron microscopy is that_____.
A) light microscopy provides for higher magnification than electron microscopy
B) light microscopy provides for higher resolving power than electron microscopy
C) light microscopy allows one to view dynamic processes in living cells
D) light microscopy provides higher contrast than electron microscopy
Answer: C
3) In the fractionation of homogenized cells using centrifugation, the primary factor that determines whether a specific cellular component ends up in the supernatant or the pellet is the____.
A) relative solubility of the component
B) size and weight of the component
C) percentage of carbohydrates in the component
D) presence or absence of lipids in the component
Answer: B
4) What is the reason that a modern transmission electron microscope (TEM) can resolve biological images to the subnanometer level, as opposed to tens of nanometers achievable for the best super-resolution light microscope?
A) The focal length of the electron microscope is significantly longer.
B) Contrast is enhanced by staining with atoms of heavy metal.
C) Electron beams have much shorter wavelengths than visible light.
D) The electron microscope has a much greater ratio of image size to real size.
Answer: C
5) What technique would be most appropriate to use to observe the movements of condensed chromosomes during cell division?
A) standard light microscopy
B) scanning electron microscopy
C) transmission electron microscopy
Answer: A
6) A newspaper ad for a local toy store indicates that an inexpensive toy microscope available for a small child is able to magnify specimens nearly as much as the more costly microscope available in your college lab. What is the primary reason for the price difference?
A) The toy microscope does not have the same fine control for focus of the specimen.
B) The toy microscope magnifies a good deal, but has low resolution and therefore poor quality images.
C) The college microscope produces greater contrast in the specimens.
D) The toy microscope usually uses a different wavelength of light source.
Answer: B
7) All of the following are part of a prokaryotic cell EXCEPT ___.
A) a cell wall
B) a plasma membrane
C) ribosomes
D) an endoplasmic reticulum
Answer: D
8) Cell size is limited by___ .
A) the number of proteins within the plasma membrane
B) the surface area of mitochondria in the cytoplasm
C) surface to volume ratios
D) the size of the endomembrane system
Answer: C
9) Which of the following is a major difference between prokaryotic cells and eukaryotic cells?
A) Prokaryotes have cells while eukaryotes do not.
B) Eukaryotic cells have more intracellular organelles than prokaryotes.
C) Prokaryotes are not able to carry out aerobic respiration, relying instead on anaerobic metabolism.
D) Prokaryotes are generally larger than eukaryotes.
Answer: B
10) You have a cube of modeling clay in your hands. Which of the following changes to the shape of this cube of clay will decrease its surface area relative to its volume?
A) Pinch the edges of the cube into small folds.
B) Flatten the cube into a pancake shape.
C) Round the clay up into a sphere.
D) Stretch the cube into a long, shoebox shape.
Answer: C
11) Prokaryotes are classified as belonging to two different domains. What are the domains?
A) Bacteria and Eukarya
B) Bacteria and Archaea
C) Archaea and Protista
D) Bacteria and Protista
Answer: B
12) Which structure is common to plant and animal cells?
A) chloroplast
B) central vacuole
C) mitochondrion
D) centriole
Answer: C
13) Which of the following is present in a prokaryotic cell?
A) mitochondrion
B) ribosome
C) chloroplast
D) ER
Answer: B
14) In a bacterium, we will find DNA in ____.
A) a membrane-enclosed nucleus
B) mitochondria
C) the nucleoid
D) ribosomes
Answer: C
15) Which organelle or structure is absent in plant cells?
A) mitochondria
B) microtubules
C) centrosomes
D) peroxisomes
Answer: C
16) What is the function of the nuclear pore complex found in eukaryotes?
A) It regulates the movement of proteins and RNAs into and out of the nucleus.
B) It synthesizes the proteins required to copy DNA and make mRNA.
C) It selectively transports molecules out of the nucleus, but prevents all inbound molecules from entering the nucleus.
D) It assembles ribosomes from raw materials that are synthesized in the nucleus.
Answer: A
17) Which of the following macromolecules leaves the nucleus of a eukaryotic cell through pores in the nuclear membrane?
A) DNA
B) amino acids
C) mRNA
D) phospholipids
Answer: C
18) Which of the following statements correctly describes some aspect of protein secretion from prokaryotic cells?
A) Prokaryotes cannot secrete proteins because they lack an endomembrane system.
B) The mechanism of protein secretion in prokaryotes is probably the same as that in eukaryotes.
C) Proteins secreted by prokaryotes are synthesized on ribosomes bound to the cytoplasmic surface of the plasma membrane.
D) Prokaryotes cannot secrete proteins because they lack ribosomes.
Answer: C
19) Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules?
A) lipids
B) glycogen
C) proteins
D) nucleic acids
Answer: C
20) The nuclear lamina is an array of filaments on the inner side of the nuclear membrane. If a method were found that could cause the lamina to fall into disarray, what would you most likely expect to be the immediate consequence?
A) the loss of all nuclear function
B) the inability of the nucleus to divide during cell division
C) a change in the shape of the nucleus
D) failure of chromosomes to carry genetic information
Answer: C