Question 1

The complex of proteins and DNA in a nondividing cell is called
A) chromatin.
B) a nucleolus.
C) a ribosome.
D) a lysosome.

Accepted Answer

Chromatin refers to the complex of DNA and proteins (including histones) that makes up the chromosomes within the nucleus of a nondividing cell. The other answer choices are different cellular structures with distinct functions.

Question 2

You are told that the cells on a microscope slide are plant, animal, or bacterial. You look at them through a microscope and see cell walls and membrane-bound organelles. You conclude correctly that the cells
A) are plant cells.
B) are animal cells.
C) are bacterial cells.
D) could be either plant or bacterial cells.

Accepted Answer

The presence of cell walls and membrane-bound organelles indicates that the cells are plant cells. Animal cells do not have cell walls, and bacterial cells do not have membrane-bound organelles. The option of "could be either plant or bacterial cells" is incorrect as bacterial cells do not have membrane-bound organelles.

Question 3

Which of the following statements about cellular metabolism is false?
A) Cellular metabolism includes different processes that require different conditions.
B) Cellular metabolism can occur within organelles.
C) Cellular metabolism occurs in animal but not plant cells.
D) Cellular metabolism often occurs on the surfaces of internal membranes.

Accepted Answer

Cellular metabolism occurs in both animal and plant cells.

Question 4

During cell reproduction, chromatin fibers coil up into structures called
A) ribosomes.
B) lysosomes.
C) chromosomes.
D) nucleoli.

Accepted Answer

During cell reproduction, chromatin fibers condense and coil tightly to form distinct structures called chromosomes.

Question 5

The endomembrane system includes all of the following organelles except the
A) plasma membrane.
B) endoplasmic reticulum.
C) peroxisome.
D) Golgi apparatus.

Accepted Answer

The endomembrane system includes the plasma membrane, endoplasmic reticulum, Golgi apparatus, lysosomes, and vacuoles. Peroxisomes are not considered part of the endomembrane system because they form from buds on the endoplasmic reticulum or other peroxisomes, not from the Golgi apparatus.

Question 6

The cells that produce hair made of protein contain a lot of ________, while the cells that produce the oils that coat the hair contain a lot of ________.
A) smooth endoplasmic reticulum; lysosomes
B) rough endoplasmic reticulum; smooth endoplasmic reticulum
C) smooth endoplasmic reticulum; rough endoplasmic reticulum
D) microbodies; lysosomes

Accepted Answer

Cells that produce hair, which is made of protein, contain a lot of rough endoplasmic reticulum (RER) because the RER is involved in the synthesis of proteins. The cells that produce oils contain a lot of smooth endoplasmic reticulum (SER) because the SER is involved in the synthesis of lipids, including oils.

Question 7

The nucleus of a cell
A) is surrounded by a single layer of membrane.
B) is contained within the nucleolus.
C) contains DNA.
D) is the primary location of protein synthesis.

Accepted Answer

The nucleus of a cell contains DNA, which is the genetic material of the cell. Therefore, choice C is the best choice. The other choices are incorrect: A is false because the nucleus is surrounded by a double membrane, B is false because the nucleolus is a substructure within the nucleus, and D is false because protein synthesis primarily occurs in the cytoplasm, not in the nucleus.

Question 8

Which of the following statements regarding the endomembrane system is false?
A) The endomembrane system is involved in the synthesis, storage, and export of important molecules.
B) The endomembrane system includes the rough and smooth endoplasmic reticulum.
C) The endomembrane system includes the nuclear envelope.
D) The endomembrane system is a system of interrelated membranes that are all physically connected.

Accepted Answer

The endomembrane system is indeed involved in various cellular processes including synthesis, storage, and export of molecules, and includes components like the rough and smooth endoplasmic reticulum and the nuclear envelope. However, not all components of the endomembrane system are physically connected; they communicate and transfer materials via vesicles.

Question 9

Secretory proteins are
A) produced by ribosomes on the smooth endoplasmic reticulum.
B) chemically modified in the nucleus.
C) produced by the cell for internal use.
D) released from the cell through the plasma membrane.

Accepted Answer

Secretory proteins are produced by ribosomes on the rough endoplasmic reticulum, which then moves to the Golgi apparatus for modification and sorting. After processing, these proteins are packaged in vesicles and transported to the plasma membrane to be released outside the cell. Therefore, choice D is the best answer as it correctly describes the final destination of secretory proteins.

Question 10

The membranous compartmentalization of a cell
A) divides the cell into two equal-sized halves.
B) allows different chemical conditions to be maintained in different parts of the cell.
C) requires the presence of a cell wall.
D) is common to both prokaryotes and eukaryotes.

Accepted Answer

Membranous compartmentalization occurs in eukaryotic cells, and allows for different chemical conditions to be maintained in different parts of the cell, such as the separation of the nucleus from the cytoplasm by the nuclear envelope, and the separation of different organelles by their respective membranes. It does not involve division of the cell into two equal-sized halves, require a cell wall, or occur in prokaryotic cells.

Question 11

The function of the nucleolus is
A) to manufacture polypeptides.
B) to manufacture ribosomal RNA.
C) intracellular digestion.
D) to store chromatin.

Accepted Answer

The nucleolus is responsible for manufacturing ribosomal RNA (rRNA), which is a crucial component of ribosomes. Ribosomes are responsible for protein synthesis, and without rRNA, they cannot function properly.

Question 12

Smooth endoplasmic reticulum
A) stores calcium ions in muscle cells.
B) is the major site of carbohydrate synthesis in eukaryotic cells.
C) produces proteins for cell membranes.
D) helps assemble ribosomes for protein synthesis.

Accepted Answer

The smooth endoplasmic reticulum stores calcium ions in muscle cells, which are important for muscle contraction.

Question 13

Protein synthesis requires the use of mRNA, which
A) is made in the nucleolus.
B) must be made by the ribosomes.
C) is translated by the ribosomes into the amino acid sequences of proteins.
D) carries the message to the nucleus to synthesize new DNA during cell division.

Accepted Answer

mRNA carries the genetic information from DNA in the nucleus to ribosomes in the cytoplasm where it is translated into the amino acid sequence of proteins through the process of protein synthesis. Option A is incorrect because the mRNA is transcribed in the nucleus not the nucleolus. Option B is incorrect because the ribosomes translate the mRNA not make it. Option D is incorrect because mRNA does not carry messages to the nucleus for DNA synthesis.

Question 14

Which of the following structures is/are used by prokaryotes for attaching to surfaces?
A) flagella
B) nucleoid
C) anchoring junctions
D) capsule

Accepted Answer

Prokaryotes use a capsule, a structure made of polysaccharides, to attach to surfaces. The capsule can protect the cell and also help it adhere to surfaces. Flagella are used for motility, nucleoid is the region that contains the genetic material, and anchoring junctions are found in eukaryotic cells and are involved in cell-cell adhesion.

Question 15

Which location in the cell is unlikely to contain ribosomes or ribosomal subunits?
A) nuclear envelope
B) plasma membrane
C) endoplasmic reticulum
D) cytoplasm

Accepted Answer

Ribosomes, which are essential for protein synthesis, are found in various locations within a cell, including the cytoplasm, on the endoplasmic reticulum, and around the nuclear envelope. However, they are not typically associated with the plasma membrane.

Question 16

The main function of the rough endoplasmic reticulum is the production of
A) mitochondria and proteins secreted by the cell.
B) hydrogen peroxide and steroid hormones secreted by the cell.
C) ribosomes and steroid hormones.
D) membrane and proteins secreted by the cell.

Accepted Answer

The rough endoplasmic reticulum (RER) is studded with ribosomes, which synthesize proteins that are then folded and modified in the RER. The RER is also involved in the production of membrane proteins and lipids. These proteins and lipids can be incorporated into the RER membrane or transported to other parts of the cell via vesicles. Therefore, the main function of the RER is the production of membrane and proteins secreted by the cell. Choices A, B, and C are incorrect because the production of mitochondria, hydrogen peroxide, and steroid hormones do not occur in the RER.

Question 17

An immune system cell called the plasma cell produces thousands of antibodies (a type of protein) per second for release into the body. What type of intracellular structure would you expect to be very prominent within the cell?
A) the smooth endoplasmic reticulum
B) the rough endoplasmic reticulum
C) peroxisome
D) microtubules

Accepted Answer

The rough endoplasmic reticulum (RER) is responsible for protein synthesis and is where the antibodies would be produced in the plasma cell. As the antibodies are proteins, a large and active RER would be necessary in the cell. The other structures mentioned (smooth endoplasmic reticulum, peroxisome, microtubules) would not be directly involved in the production of antibodies.

Question 18

Which of the following statements about internal membranes in eukaryotic cells is false?
A) In eukaryotic cells, internal membranes greatly increase a cell's total membrane area.
B) In eukaryotic cells, internal membranes provide an additional area for many metabolic processes to occur.
C) In eukaryotic cells, internal membranes form membranous compartments called organelles.
D) In eukaryotic cells, internal membranes standardize the internal environment of all cellular organelles.

Accepted Answer

Internal membranes in eukaryotic cells do not standardize the internal environment of all cellular organelles. Rather, they compartmentalize and create different environments suited for specific cellular processes within each organelle.

Question 19

A bacterial cell's DNA is found in its
A) ribosomes.
B) nucleus.
C) nucleoid.
D) capsule.

Accepted Answer

A bacterial cell's DNA is found in the nucleoid. The nucleoid is a region within the cell that lacks a membrane and contains the genetic material of the cell. Ribosomes are responsible for protein synthesis, while a nucleus is found only in eukaryotic cells and contains the genetic material in a membrane-bound structure. A capsule is a protective layer outside of the cell membrane but does not contain the DNA of the cell.

Question 20

Unlike animal cells, plant cells have ________ and ________. Unlike plant cells, animal cells have ________.
A) chloroplasts; cell walls; centrioles
B) centrioles; chloroplasts; cell walls
C) chloroplasts; cell walls; a nucleus
D) centrioles; cell walls; large central vacuoles

Accepted Answer

Plant cells have chloroplasts and cell walls, which are not found in animal cells. Animal cells have centrioles, which are not found in plant cells.

Quiz 4: A Tour of the Cell

The complex of proteins and DNA in a nondividing cell is called

You are told that the cells on a microscope slide are plant, animal, or bacterial. You look at them through a microscope and see cell walls and membrane-bound organelles. You conclude correctly that the cells

Which of the following statements about cellular metabolism is false?

During cell reproduction, chromatin fibers coil up into structures called

The endomembrane system includes all of the following organelles except the

The cells that produce hair made of protein contain a lot of , while the cells that produce the oils that coat the hair contain a lot of .

The nucleus of a cell

Which of the following statements regarding the endomembrane system is false?

Secretory proteins are

The membranous compartmentalization of a cell

The function of the nucleolus is

Smooth endoplasmic reticulum

Protein synthesis requires the use of mRNA, which

Which of the following structures is/are used by prokaryotes for attaching to surfaces?

Which location in the cell is unlikely to contain ribosomes or ribosomal subunits?

The main function of the rough endoplasmic reticulum is the production of

An immune system cell called the plasma cell produces thousands of antibodies (a type of protein) per second for release into the body. What type of intracellular structure would you expect to be very prominent within the cell?

Which of the following statements about internal membranes in eukaryotic cells is false?

A bacterial cell's DNA is found in its

Unlike animal cells, plant cells have and . Unlike plant cells, animal cells have .