Question 1

Consider these two examples of tissues: 1. The body of a slime mold that flows over a rotten log appears to lack any partitioning into distinct cells; however, it does become cellular when it changes form and produces spores.
2) The surfaces of parasitic flatworms and some insect tissues are "syncytial" layers of living material that developed from a single cell but now contain many nuclei, though they lack partitioning by cell membranes. These tissues actively consume food and produce wastes.
If the cell theory states that "all living things are composed of cells," then
A) neither of these are living tissues because they violate the cell theory.
B) these examples prove that some vital force is involved, beyond normal cell structures, to give life to living organisms.
C) these tissues are obviously a bridge between nonliving and primitive living cells.
D) the general concept of life-is-cellular still holds, since these organisms still utilize cells at some time in their life cycles, though these examples show that cell membranes can be abandoned.
E) these examples demonstrate that cell membranes are a necessity if a cell is to be classified as "living."

Accepted Answer

These examples demonstrate that while some living tissues may lack partitioning by cell membranes at some point in their life cycle, they still utilize cells at other times. Therefore, the general concept that life is cellular still holds, but these examples show that cell membranes can sometimes be abandoned.

Question 2

Which structure regulates passage of molecules into and out of the bacterial cell?
A) plasma membrane
B) nucleus
C) mitochondria
D) chloroplast
E) flagella

Accepted Answer

The plasma membrane is the structure that regulates passage of molecules into and out of the bacterial cell. This membrane is selectively permeable, allowing some molecules to pass through while preventing others from entering or leaving the cell.

Question 3

In some bacteria, the outermost layer is a gelatinous sheath known as
A) the nucleus.
B) the capsule.
C) the cell wall.
D) the cell membrane.
E) the DNA.

Accepted Answer

The gelatinous sheath layer is called the capsule. The nucleus is typically found in eukaryotic cells, not bacteria. The cell wall and cell membrane are inner layers of the bacterial cell, not the outermost layer. DNA is found within the cell, not as an outermost layer.

Question 4

What evidence would suggest that the fluid in the nucleus is different from the cytoplasm?
A) There is no pH difference between the two fluids.
B) Nucleoplasm flows freely back and forth between the nucleus and the cytoplasm.
C) Nuclear pores only permit passage of certain molecules into and out of the nucleus.
D) Light microscopy reveals no differences between the fluid within the nucleus and the fluid outside of the nucleus.

Accepted Answer

Nuclear pores only allow certain molecules to pass through, indicating differences in the chemical composition of the fluids on either side of the nuclear membrane. The other choices do not provide evidence for a difference in the fluid composition.

Question 5

A compound would make a good antibiotic if it affects a structure or process only found in bacterial cells and not in our eukaryotic cells. Which of the following actions would theoretically make a good antibiotic?
A) prevents repair of the peptidoglycan cell wall
B) damages the nuclear membrane
C) damages DNA
D) prevents ribosomes from producing proteins
E) stops cellular respiration

Accepted Answer

Peptidoglycan is a unique component of bacterial cell walls that is not found in eukaryotic cells. Therefore, a compound that prevents repair of the peptidoglycan cell wall would only affect bacterial cells and not harm our own cells.

Question 6

Ribosomal RNA is produced in the
A) nucleolus.
B) Golgi apparatus.
C) ribosomes.
D) rough endoplasmic reticulum.
E) smooth endoplasmic reticulum.

Accepted Answer

Ribosomal RNA (rRNA) is produced in the nucleolus, a distinct structure within the nucleus of a cell. The nucleolus is responsible for ribosome biogenesis and assembly, including the production of rRNA.

Question 7

Circulating red blood cells in your body do not contain a nucleus and other organelles. Are these cells living?
A) Yes, because they are actively metabolizing and once contained organelles.
B) Yes, because they are capable of moving throughout the body in the circulation.
C) No, because they do not contain a nucleus, they cannot be living.
D) No, because red blood cells do not actively metabolize.
E) No, because they are now only part of a once living cell.

Accepted Answer

Red blood cells are considered living despite lacking a nucleus and other organelles because they are actively metabolizing and were once fully equipped cells during their development stages.

Question 8

Which of the following is the largest eukaryotic organelle?
A) ribosome
B) nucleus
C) lysosome
D) mitochondria
E) Golgi apparatus

Accepted Answer

The nucleus is the largest eukaryotic organelle, containing the cell's genetic material and regulating gene expression. The other organelles listed (ribosomes, lysosomes, mitochondria, and Golgi apparatus) are much smaller in size.

Question 9

Which of the following structure(s) is/are only found in a plant cell?
A) centrioles
B) chloroplast
C) chromosomes
D) nucleus
E) lysosome

Accepted Answer

Chloroplasts are organelles that are unique to plant cells and are responsible for photosynthesis. Centrioles are found only in animal cells and are involved in cell division. Chromosomes, nucleus, and lysosomes are found in both plant and animal cells.

Question 10

Which of the following cell organelles is a good target for antibacterial drugs?
A) plasma membrane
B) DNA
C) ribosomes
D) cytoplasm
E) endoplasmic reticulum

Accepted Answer

Ribosomes are the site of protein synthesis in both bacterial and eukaryotic cells, but they differ in their molecular composition. Antibacterial drugs can specifically target bacterial ribosomes without harming the ribosomes in human cells, making them a good target for antibacterial drugs.

Question 11

According to the cell theory
A) all organisms are composed of tissues.
B) the smallest unit of life is a nucleus.
C) animals but not plants are composed of cells.
D) a multicellular organism is composed of many cells.
E) new cells arise only from preexisting cells.

Accepted Answer

The cell theory states that all living organisms are composed of one or more cells, the cell is the basic unit of life, and all new cells arise only from preexisting cells. Therefore, option E is the best choice as it states a key aspect of the cell theory.

Question 12

Which of the following is a prokaryotic cell?
A) plant cell
B) liver cell
C) muscle cell
D) paramecium
E) bacterium

Accepted Answer

Prokaryotic cells are cells without a nucleus or other organelles. Bacteria are the most well-known example of prokaryotic cells. A, B, and C are examples of eukaryotic cells, which have a nucleus and other membrane-bound organelles. Paramecium is a single-celled eukaryotic organism.

Question 13

The cell theory states
A) all organisms are composed of only one cell.
B) organelles are the basic living unit of structure and function of organisms.
C) all organisms are composed of cells.
D) all organisms are composed of only one cell AND organelles are the basic living unit of structure and function of organisms.
E) all multicellular organisms are unicellular at some point in their life cycle.

Accepted Answer

The cell theory states that all organisms are composed of cells. It does not specify how many cells an organism may have or whether organelles are the basic unit of structure and function. It simply states that cells are the basic unit of life and all living things are composed of cells. Therefore, choice C is the best answer.

Question 14

Within eukaryotic cells, which organelle is surrounded by a double membrane and carries the coding that determines protein synthesis?
A) smooth endoplasmic reticulum
B) lysosome
C) nucleolus
D) nucleus
E) rough endoplasmic reticulum

Accepted Answer

The organelle surrounded by a double membrane that carries the coding for protein synthesis is the nucleus. The nucleolus, within the nucleus, is responsible for the assembly of ribosomes, which are involved in protein synthesis. The smooth and rough endoplasmic reticulum are involved in protein synthesis and modification, but do not carry the genetic information. Lysosomes are responsible for breaking down cellular waste and do not play a role in protein synthesis.

Question 15

A researcher samples the waters of the boiling hot springs in Yellowstone National Park. Under the microscope, she observes what appear to be living cells in the water. If these indeed are living cells, which type of cell would they most likely be?
A) eukaryotic, animal
B) eukaryotic, plant
C) eukaryotic, fungi
D) prokaryotic, archaea
E) prokaryotic, bacteria

Accepted Answer

The extreme conditions of the boiling hot springs in Yellowstone National Park suggest that any living cells present would likely be adapted to survive in such harsh conditions. Prokaryotic archaea are known to thrive in extreme environments such as hot springs, so they are the most likely type of cell present in this scenario.

Question 16

Which of the following is true concerning the cell theory?
A) Matthias Schleiden stated that animals are composed of cells.
B) Anton van Leeuwenhoek is recognized for making some of the earliest microscopes.
C) Hooke researched animal tissues and discovered that they were all made of cells.
D) Theodor Schwann came to the conclusion that cells come from preexisting cells.
E) No one knows who first used the term "cells."

Accepted Answer

Anton van Leeuwenhoek is indeed recognized for creating some of the earliest microscopes, which were crucial in the advancement of cell theory by allowing scientists to observe cells for the first time.

Question 17

Compared with a eukaryotic cell, a prokaryotic cell
A) lacks organelles beyond ribosomes.
B) is larger.
C) does not require energy.
D) is not living.
E) has no method of movement.

Accepted Answer

Prokaryotic cells lack membrane-bound organelles, such as mitochondria, chloroplasts, and endoplasmic reticulum, that are present in eukaryotic cells. However, prokaryotic cells do possess ribosomes for protein synthesis.

Question 18

Which nuclear structure(s) contain(s) the hereditary material?
A) nuclear envelope
B) chloroplasts
C) chromatin
D) nucleoplasm
E) mitochondria

Accepted Answer

Chromatin is composed of DNA and protein and is the site of the hereditary material in the nucleus.

Question 19

Surface-area-to-volume ratios indicate
A) cells must exceed a certain minimum size.
B) as cells get larger, their surface area actually decreases.
C) that the largest cells have a less proportionate need for food intake and waste removal.
D) a chicken egg is one cell which demonstrates the upper limit for metabolizing cell size.
E) as cells get larger, their surface area gets larger but at a slower rate than the volume increases.

Accepted Answer

As cells get larger, their volume increases at a faster rate than their surface area, resulting in a smaller surface-area-to-volume ratio. This means that larger cells have a proportionally smaller surface area available for nutrient and waste exchange per unit of volume, making it more difficult for them to maintain their metabolic needs. This limits the maximum size a cell can reach before it becomes unable to sustain itself.

Question 20

The nucleolus
A) contains RNA and is found in the nucleus.
B) contains polysaccharides and is found in the nucleus.
C) contains RNA and is found in the cytoplasm.
D) contains DNA and is found in the cytoplasm.
E) contains ribosome subunits and is found in the cytoplasm.

Accepted Answer

The nucleolus is a structure found within the nucleus of eukaryotic cells. It is a prominent structure that is composed of RNA and proteins, and its primary function is to produce ribosomes. Therefore, choice A is the correct answer, as it accurately describes the composition and location of the nucleolus. Choices B, C, D, and E are incorrect, as they do not accurately describe the composition or location of the nucleolus.

Quiz 3: Cell Structure and Function

Which structure regulates passage of molecules into and out of the bacterial cell?

In some bacteria, the outermost layer is a gelatinous sheath known as

What evidence would suggest that the fluid in the nucleus is different from the cytoplasm?

A compound would make a good antibiotic if it affects a structure or process only found in bacterial cells and not in our eukaryotic cells. Which of the following actions would theoretically make a good antibiotic?

Ribosomal RNA is produced in the

Circulating red blood cells in your body do not contain a nucleus and other organelles. Are these cells living?

Which of the following is the largest eukaryotic organelle?

Which of the following structure(s) is/are only found in a plant cell?

Which of the following cell organelles is a good target for antibacterial drugs?

According to the cell theory

Which of the following is a prokaryotic cell?

The cell theory states

Within eukaryotic cells, which organelle is surrounded by a double membrane and carries the coding that determines protein synthesis?

A researcher samples the waters of the boiling hot springs in Yellowstone National Park. Under the microscope, she observes what appear to be living cells in the water. If these indeed are living cells, which type of cell would they most likely be?

Which of the following is true concerning the cell theory?

Compared with a eukaryotic cell, a prokaryotic cell

Which nuclear structure(s) contain(s) the hereditary material?

Surface-area-to-volume ratios indicate

The nucleolus