Deck 7: Inside the Cell

Question 1

Which of the following is not a characteristic that chloroplasts and mitochondria share?

A) They both have their own DNA.
B) They are both part of the endomembrane system.
C) They are capable of reproducing themselves.
D) They both have multiple membranes.

Answer 1

B

Question 2

You arrive late to lecture and your professor is describing a feature of the nucleus that provides it with structural support. You are not sure which feature is being discussed, but because you read the book before you came to class, you are fairly certain that it is

A) the nuclear lamina.
B) the nucleolus.
C) the nucleoplasm.
D) the nucleus pore.

Answer 2

A

Question 3

What is the function of the nuclear pore complex?

A) It assembles ribosomes from raw materials that are synthesized in the nucleus.
B) It synthesizes components of the endomembrane system.
C) It synthesizes and repairs DNA.
D) It regulates movement of materials across the nuclear envelope.

Answer 3

D

Question 4

Which of the following is present in a prokaryotic cell?

A) chloroplast
B) ribosome
C) mitochondrion
D) endoplasmic reticulum
E) nuclear envelope

Question 5

Which of the following components would you expect to find in any type of living organism?

A) microtubule
B) mitochondria
C) chromosome
D) nucleus
E) lysosome

Question 6

What is the site of synthesis of proteins for export secretion from the cell)?

A) ribosomes that attach to the endoplasmic reticulum
B) ribosomes that attach to the Golgi complex
C) ribosomes that attach to the outer mitochondrial membrane
D) free ribosomes

Question 7

Mitochondria are separated into two compartments, the matrix and the intermembrane space, by their inner and outer membranes. How does the presence of two compartments contribute to the function of mitochondria?

A) The double- membrane feature of mitochondria is what enables them to glycosylate proteins.
B) The two compartments permit different but complementary functions to be accomplished in the organelle.
C) It enables mitochondrial DNA and ribosomes to remain separated from the functional compartment of the mitochondria.

Question 8

Why are lysosomes considered part of the endomembrane system?

A) They deposit end- products of digestion in the endoplasmic reticulum.
B) Lysosomes are not part of the endomembrane system.
C) They facilitate movement between stacks of the Golgi.
D) They are formed from products synthesized by the endoplasmic reticulum and processed by the Golgi.

Question 9

What is the most likely role of a cell that contains an extensive smooth ER?

A) It plays a role in storage.
B) It plays a role in immune function.
C) It synthesizes large quantities of lipids.
D) It actively exports protein molecules.

Question 10

One function of peroxisomes is alcohol detoxification. In which of the following locations would you expect to find large quantities of peroxisomes?

A) in liver tissue of people who drink large quantities of alcohol
B) in heart muscle of all people
C) in the stomach of people who drink large quantities of alcohol
D) in liver tissue of people who consume high- fat diets

Question 11

What can you infer about high- molecular- weight proteins that cannot be transported into the nucleus?

A) They are foreign proteins.
B) They have been tagged for destruction.
C) They lack nuclear localization signals NLS).
D) They are defective proteins.

Question 12

As part of our immune system, neutrophil cells engulf micro- organisms or foreign particles. The process by which the neutrophil does this is known as

A) pinocytosis.
B) phagocytosis.
C) receptor- mediated endocytosis.
D) exocytosis.

Question 13

You have a distant cousin, age 4, who is always tired and fatigued and is not able to play games and sports like other healthy children. He is most likely to have an enzyme deficiency or defect associated with which intracellular organelle?

A) Golgi stacks
B) mitochondria
C) lysosomes
D) peroxisomes

Question 14

Which of the following represents a major difference between prokaryotic cells and eukaryotic cells?

A) Prokaryotes are a more homogenous group of organisms than eukaryotes, which include protozoa, plants, and animals.
B) Eukaryotic cells tend to have much more extensive inner membrane systems and larger numbers of intracellular organelles than prokaryotes.
C) Prokaryotes, not eukaryotes, have cell walls.
D) Prokaryotes are unable to carry out aerobic respiration, a process that requires a complex inner- membrane system.

Question 15

How is the nuclear membrane related to the endoplasmic reticulum?

A) The nucleolus is present in the nucleus, but communicates directly with the endoplasmic reticulum.
B) The inner and outer bilayers of the nuclear envelope are separated by a space that is continuous with the space inside the endoplasmic reticulum, thus providing direct contact between the two structures.
C) Ribosomes that exit the nucleus through the nuclear pore complex attach to ribosome receptor locations on the endoplasmic reticulum, thus providing a means of communication between the two structures.
D) The nuclear lamina anchors the endoplasmic reticulum, providing structural support and communication through direct contact.

Question 16

The small intestine is the site of digestion and absorption of nutrients. A single layer of epithelial cells lines the small intestine. In the duodenum the first section of the small intestine), these epithelial cells secrete large quantities of digestive enzymes. Which of the following features would be typical of these epithelial cells?

A) They have larger nuclei than cells that secrete large quantities of lipids.
B) They have more smooth endoplasmic reticulum than rough endoplasmic reticulum.
C) They contain large numbers of lysosomes.
D) They contain large quantities of rough endoplasmic reticulum.

Question 17

You are studying an organism and note that its proteins fail to be glycosylated. A deficiency in which of the following organelles is likely the cause?

A) peroxisomes
B) mitochondria
C) rough endoplasmic reticulum
D) Golgi apparatus

Question 18

Which of the following organelles is involved in the oxidation of fatty acids or ethanol?

A) mitochondria
B) peroxisomes
C) rough endoplasmic reticulum
D) Golgi apparatus

Question 19

What is a purpose of the cell wall for both prokaryotes and plant cells?

A) to provide a means of cell- cell interaction
B) to protect the cell from the effects of a hypotonic environment
C) to regulate the passage of solutes into and out of the cell
D) to enable the cell to obtain nutrients from its environment

Question 20

Mitochondrial DNA codes for about 13 proteins depending on the species of organism). These 13 proteins account for a small proportion of the proteins present in mitochondria. The remaining proteins are coded for by nuclear DNA. What is the most likely explanation for how these proteins find their way to the mitochondria?

A) random transport vesicles
B) signal sequences
C) attachment of ribosomes to outer mitochondrial pores and direct deposition into the inner mitochondrial compartment
D) mRNAs that are manufactured in the nucleus, but translated by mitochondrial ribosomes

Question 21

A cell is found to contain a series of damaged organelles. Which process will play a role in removal of these damaged organelles from the cytosol?

A) exocytosis
B) autophagy
C) pinocytosis
D) phagocytosis

Question 22

The evolution of eukaryotic cells most likely involved

A) anaerobic archaea taking up residence inside a larger bacterial host cell to escape toxic oxygen-the anaerobic bacterium evolved into chloroplasts.
B) acquisition of an endomembrane system and subsequent evolution of mitochondria from a portion of the Golgi apparatus.
C) an endosymbiotic fungal cell evolving into the nucleus.
D) endosymbiosis of an aerobic bacterium in a larger host cell-the endosymbiont evolved into mitochondria.
E) evolutionary processes independent from prokaryotic cells, as the eukaryotic cells were found in an environment richer in oxygen.

Question 23

Flagella and cilia bend or move, imparting mobility to cells. How do these structures move?

A) Two microtubules at the core of the structure serve as motor proteins.
B) Dynein is a motor protein that hydrolyzes ATP and is responsible for movement of the cilium or flagellum.
C) Axonemes are structured such that movement is constant.
D) The basal body at the base of the structure hydrolyzes ATP, causing a conformational change that results in movement of the cilium or flagellum.

Question 24

Amoeba move by crawling over a surface amoeboid movement). Which one of the following processes is part of amoeboid movement?

A) polymerization or extension of actin filaments to form bulges in the plasma membrane
B) reinforcing the pseudopod with intermediate filaments
C) setting up microtubule extensions that vesicles can follow in the movement of cytoplasm

Question 25

Motor proteins require energy in the form of ATP. ATP hydrolysis results in a conformational change that allows the protein to move along microtubular tracks pathways). What structural component of the motor protein contains the ATP binding site and, therefore, changes shape to enable movement?

A) a location midway between the vesicle binding site and the portion of the molecule that binds to microtubular tracks
B) the portion of the molecule that binds to the microtubular track along which the vesicle is being transported
C) the portion of the molecule that binds to the vesicle being transported
D) the stalk

Question 26

To what does the 9 + 2 arrangement of microtubules, typical of cilia and eukaryotic flagella, refer?

A) the relationship between the basal body and the axoneme
B) the length of the structures
C) the arrangement of dynein arms with respect to each microtubule
D) the arrangement of microtubules within the axoneme

Question 27

Scientists found that polypeptides that are normally synthesized in the endoplasmic reticulum are about 20 amino acids longer when they are synthesized by ribosomes not attached to the endoplasmic reticulum. What is/are possible explanations for the greater length of these polypeptides?

A) The ribosomes that function as free ribosomes function differently than the ribosomes that are attached to the endoplasmic reticulum.
B) The 20- amino- acid sequence helps the endoplasmic reticulum package these proteins for shipping to the Golgi.
C) The 20 amino acids serve as a signal sequence that directs the forming polypeptide to the endoplasmic reticulum, where they are cleaved off during processing.
D) The protein has a different function in the cytosol than in the endoplasmic reticulum.

Question 28

You are sitting in lecture and you decide to leave the room for a minute. When you return, the professor is describing a cytoskeletal component and states that these fibres are thin and consist of two rows of protein subunits wound around each other in a long spiral. Since you left the room, you did not hear which cytoskeletal component is being referred to, but, since you read the book before you came to class, you know that it is

A) microfilaments.
B) the intermediate filaments.
C) the microtubules.
D) none of the above.

Question 29

Which of the following cytoskeletal proteins are important in changing cell shape or location any type of cell movement)?

A) Microfilaments are the only cytoskeletal proteins important in cell movement.
B) Intermediate filaments are the only cytoskeletal proteins important in cell movement.
C) Microfilaments and myosin are among the cytoskeletal proteins important in cell movement.
D) Microfilaments, microtubules, and intermediate filaments are equally important in cell movement.

Question 30

Spherocytosis is a defect associated with a defective cytoskeletal protein in red blood cells. What do you suspect is one consequence of defective cytoskeletal proteins in red blood cells?

A) a lack of oxygen- transporting proteins in the cell
B) adhering of blood cells to blood- vessel walls, causing the formation of plaque
C) insufficient energy supply in the cell
D) abnormal cell shape

Question 31

In a plant cell, where is DNA found?

A) only in the nucleus and chloroplasts
B) in the nucleus, mitochondria, and chloroplasts
C) only in the nucleus and mitochondria
D) in the nucleus, mitochondria, chloroplasts, and peroxisomes
E) only in the nucleus

Question 32

Which of the following is a basic structural difference between plant cells and animal cells?

A) The cell wall plays a major role in determining plant cell shape, but the cytoskeleton plays a major role in determining animal cell shape.
B) Plant cells contain chloroplasts, but animal cells do not.
C) Animal cells contain lysosomes, but plant cells do not.
D) Plants have cell walls, and animal cells do not.
E) All of the above apply.

Question 33

What is the function of keratin, an important intermediate filament?

A) reinforces moveable joints
B) enables the heart to contract as a unit
C) provides nutrients to neural cells of the brain and spinal cord
D) imparts impermeability to the skin and the ability to withstand mechanical stress

Question 34

Actin filaments have polarity. This means that the two ends can be identified due to structural differences. The plus end is the end to which subunits are added more rapidly or the end of polymerization. Which of the following would enable you to identify the plus end of actin filaments?

A) Determine the ionic charge of the ends of the actin filaments.
B) Add radiolabeled actin subunits to a mixture of actin filaments in which conditions favor depolymerization.
C) Add radio labeled actin subunits to a mixture of actin filaments in which conditions are favorable for polymerization.

Question 35

Researchers tried to explain how vesicular transport occurs in cells by attempting to assemble the transport components. They set up microtubular tracks along which vesicles could be transported, and they added vesicles and ATP because they knew the transport process requires energy). Yet, when they put everything together, there was no movement or transport of vesicles. What were they missing?

A) contractile microfilaments
B) endoplasmic reticulum
C) an axon
D) motor proteins

Question 36

How is the structure of kinesin related to its function?

A) Kinesin has a tail region that binds to vesicles and two heads that can attach to microtubules.
B) The kinesin tail has an ATP binding site to fuel its activities.
C) Kinesin has two heads to attach to the vesicle being moved, and a tail region that attaches to microtubules.
D) Kinesin has two intertwined polypeptides that make up the stalk and enable it to contract and shorten.

Question 37

Eukaryotic cells manufacture cytoskeletal proteins that help to maintain the cells' shapes and functions. What would you predict about these proteins?

A) They would be manufactured on free ribosomes in the cytoplasm.
B) They would be glycosylated in the Golgi apparatus.
C) They would initially contain signal sequences that would allow their entrance into the endoplasmic reticulum.
D) They might travel to the nucleus in a transport vesicle with a specific zip code.

Question 38

Which of the following would be true for lysosomes that lack mannose- 6- phosphate receptors?

A) They do not receive enzyme shipments from the Golgi apparatus.
B) They function equally as well as those that possess mannose 6- phosphate receptors.
C) They have unstable membranes.

Question 39

The liver is involved in the detoxification of many poisons and drugs. Which of the following structures is primarily involved in this process and therefore abundant in liver cells?

A) rough endoplasmic reticulum
B) transport vesicles
C) Golgi apparatus
D) smooth endoplasmic reticulum
E) nuclear envelope

Question 40

Flagella are found in both eukaryotic cells and prokaryotic cells. Despite the functional similarities of all flagella, scientists suspect that eukaryotic and prokaryotic flagella have evolved independently. Why don't they think there is a common evolutionary origin for prokaryotic and eukaryotic flagella?

A) Prokaryotic flagella do not protrude outside the cell wall, whereas eukaryotic flagella are membrane- bound extensions of cytoplasm.
B) Prokaryotic flagella do not require energy in the form of ATP.
C) Prokaryotic flagella move by rotating, whereas eukaryotic flagella undergo an undulating motion. Furthermore, eukaryotic flagella are covered by a plasma membrane and prokaryotic flagella are not.
D) Prokaryotic flagella are an adaptation to scarce nutrient supply, whereas eukaryotic flagella are designed to protect.

Question 41

What is the primary objective of cell fractionation including differential centrifugation)?

A) to separate lipid- soluble from water- soluble molecules
B) to view the structure of cell membranes
C) to determine the size of various organelles
D) to separate the major organelles
E) to sort cells based on their size and weight