Question 1

Close examination of a healthy organ reveals a lining of several layers of cells.The layers do not contain any blood vessels and one surface of the cells lines the cavity of the organ.This tissue is a type of
A)epithelium.
B)muscle tissue.
C)connective tissue.
D)neural tissue.
E)fat tissue.

Accepted Answer

The description matches that of epithelial tissue, which forms linings and coverings of organs and does not contain blood vessels.

Question 2

Which one of the following is not one of the four main tissue categories?
A)muscle tissue
B)neural tissue
C)osseous tissue
D)connective tissue
E)epithelial tissue

Accepted Answer

The four main tissue categories are epithelial tissue, connective tissue, muscle tissue, and neural tissue. While osseous tissue (bone tissue) is a type of connective tissue, it is not considered one of the main tissue categories.

Question 3

Dead skin cells are shed in thin sheets because they are held together by "spots" of proteoglycan reinforced by intermediate filaments.Such strong intercellular connections are called
A)gap junctions.
B)intermediate junctions.
C)tight junctions.
D)desmosomes.
E)junctional complexes.

Accepted Answer

Desmosomes are strong intercellular connections that anchor cells together and allow them to resist mechanical stress. They are made up of intermediate filaments that attach to a protein plaque and form a spot desmosome, which connects to corresponding desmosomes on neighboring cells. In the case of dead skin cells, these desmosomes hold together the thin sheets of shed cells that are made up of layers of dead, flattened cells filled with keratin. Gap junctions, tight junctions, and intermediate junctions are all types of intercellular connections, but they do not provide the same level of mechanical strength as desmosomes. Junctional complexes are a general term for any group of intercellular connections.

Question 4

Germinative cells
A)start in the superficial layers of epithelial tissue.
B)cannot divide in the deep layers of epithelial tissue.
C)make up most of the epithelial type of tissue.
D)divide continually to produce new epithelial cells.
E)cannot function in the repair of epithelial tissue.

Accepted Answer

Germinative cells, also known as stem cells, divide continually to produce new epithelial cells for growth and repair of the tissue.

Question 5

Characteristics of epithelia include all of the following except
A)attachment.
B)avascularity.
C)regeneration.
D)polarity.
E)extracellular matrix.

Accepted Answer

Epithelial tissues lack an extracellular matrix and instead, are directly attached to a basement membrane.

Question 6

Epithelium is connected to underlying connective tissue by
A)keratin.
B)interfacial canals.
C)a basement membrane.
D)a reticular lamina.
E)proteoglycan.

Accepted Answer

The correct answer is C, as epithelium is attached to underlying connective tissue by a specialized extracellular matrix known as the basement membrane. This structure is composed of layers of glycoproteins, collagen, and proteoglycans that anchor the epithelial cells to the connective tissue and provide structural support. Choices A, B, D, and E are not correct, as keratin is a structural protein found in skin, hair, and nails; interfacial canals are not a part of the attachment between epithelium and connective tissue; the reticular lamina is a component of the basement membrane, not the attachment site itself; and proteoglycan is a component of the basement membrane, but not the only one involved in the attachment.

Question 7

Functions of epithelia include all of the following except
A)providing physical protection.
B)controlling permeability.
C)absorption.
D)producing specialized secretions.
E)supporting muscle cells.

Accepted Answer

Epithelial tissues do not provide support for muscle cells. Rather, they line body surfaces and cavities, and their functions include physical protection, controlling permeability, absorption, and producing specialized secretions.

Question 8

A type of intercellular junction that stops materials from crossing an epithelium between cells is called a(n)
A)tight junction.
B)gap junction.
C)intermediate junction.
D)desmosome.
E)All of the answers are correct.

Accepted Answer

Tight junctions are specialized structures that seal the intercellular space and prevent materials from passing between cells, making them the best choice for the given question. Gap junctions, intermediate junctions, and desmosomes are all types of intercellular junctions, but they do not specifically prevent materials from crossing between cells. Therefore, choices B, C, D, and E are incorrect.

Question 9

Epithelial cells exhibit modifications that adapt them for
A)contraction.
B)conduction.
C)secretion.
D)circulation.
E)support.

Accepted Answer

Epithelial cells are specialized to perform a variety of functions, including secretion, absorption, filtration, and protection. These functions depend on specialized modifications such as the presence of cilia or microvilli, specialized cell junctions, and the ability to secrete or absorb various substances. Among these modifications, secretion is a prominent function performed by many types of epithelial cells, such as those in the digestive, respiratory, and excretory systems.

Question 10

The junction type that lets neighboring cells exchange small molecules is the
A)desmosome.
B)hemidesmosome.
C)gap junction.
D)tight junction.
E)zonula adherens.

Accepted Answer

Gap junctions are specialized junctions that allow neighboring cells to communicate and exchange small molecules such as ions, second messengers, and metabolic substrates. They are made up of proteins called connexins that form channels between the two cells. Desmosomes and hemidesmosomes provide mechanical strength and are involved in cell adhesion, while tight junctions and zonula adherens are involved in creating a tight barrier between cells to regulate the passage of molecules.

Question 11

Epithelial cells that are adapted for absorption usually have ________ at their free surface.
A)mitochondria
B)cilia
C)microvilli
D)junctional complexes
E)Golgi complexes

Accepted Answer

Cells adapted for absorption have increased surface area to enhance the efficiency of nutrient absorption. Microvilli increase surface area by forming numerous projections on the cell surface, allowing for a greater amount of nutrient absorption. Mitochondria are important for energy production, cilia are responsible for movement, junctional complexes are involved in cell adhesion and Golgi complexes are involved in protein modification and secretion, none of which are directly related to absorption.

Question 12

A layer of glycoproteins that prevents leakage of materials from connective tissues into epithelia is the
A)integral proteins.
B)clear layer.
C)matrix.
D)dense layer.
E)ground substance.

Accepted Answer

The clear layer, also known as the basal lamina, is a layer of glycoproteins that acts as a barrier to prevent the leakage of materials from connective tissues into the epithelial tissues.

Question 13

You would find pseudostratified columnar epithelium lining the
A)trachea.
B)urinary bladder.
C)secretory portions of the pancreas.
D)surface of the skin.
E)stomach.

Accepted Answer

Pseudostratified columnar epithelium is commonly found lining the respiratory tract, including the trachea. It is important for its protective and respiratory functions.

Question 14

Epithelia specialized for providing sensations of smell,taste,sight,equilibrium,and hearing are known as
A)neuroepithelia.
B)psychoepithelia.
C)neuropsychoepithelia.
D)multilaminar epithelia.
E)protective epithelia.

Accepted Answer

The term used for epithelia specialized for providing sensations of smell, taste, sight, equilibrium, and hearing is neuroepithelia. These epithelia have specialized sensory cells that detect the stimuli and transmit signals to the nervous system. Therefore, option A, neuroepithelia, is the best choice. The other options like psychoepithelia, neuropsychoepithelia, multilaminar epithelia, and protective epithelia do not accurately describe the specialized functions of these epithelia.

Question 15

Which tissue lines the small intestine and the stomach?
A)simple squamous epithelium
B)simple cuboidal epithelium
C)simple columnar epithelium
D)pseudostratified ciliated columnar epithelium
E)stratified squamous epithelium

Accepted Answer

Simple columnar epithelium lines the small intestine and stomach, and is specialized for absorption and secretion.

Question 16

The tissue that always has an apical and a basal surface is ________ tissue.
A)epithelial
B)connective
C)muscle
D)basal
E)apical

Accepted Answer

Epithelial tissue always has an apical (top) surface and a basal (bottom) surface, which allows it to function in protection, absorption, and secretion. Connective tissue, muscle, and basal tissue do not necessarily have these distinct surfaces.

Question 17

The heart and blood vessels are lined by ________ epithelium.
A)pseudostratified columnar
B)transitional
C)simple cuboidal
D)simple columnar
E)simple squamous

Accepted Answer

The heart and blood vessels are lined by simple squamous epithelium, which is a thin and flat layer of cells that allows for easy diffusion of gases and nutrients. This type of epithelium is well-suited for areas where rapid diffusion is necessary, such as the lungs and blood vessels.

Question 18

Examination of a tissue sample reveals groups of cells united by junctional complexes and interlocking membranes.The cells have one free surface and lack blood vessels.The tissue is most likely ________ tissue.
A)muscle
B)neural
C)epithelial
D)connective
E)adipose

Accepted Answer

The presence of junctional complexes and interlocking membranes, along with the lack of blood vessels, suggest an epithelial tissue. The presence of a free surface further supports this choice.

Question 19

In stratified epithelia adapted to resist mechanical forces,which of the following types of cell-to-cell junctions are especially abundant?
A)tight junctions
B)basolateral junctions
C)gap junctions
D)hemidesmosomes
E)desmosomes

Accepted Answer

Desmosomes are intercellular junctions that act as spot welds or adhesive points to anchor intermediate filaments to adjacent cells, which reinforces the cytoskeleton and allows for resistance against mechanical stress. Stratified epithelia adapted to resist mechanical forces, such as the skin and the lining of the oral cavity, have numerous desmosomes.

Question 20

Transitional epithelium is found
A)lining the urinary bladder.
B)lining the ducts that drain sweat glands.
C)lining kidney tubules.
D)lining the stomach.
E)at the surface of the skin.

Accepted Answer

Transitional epithelium is a specialized type of epithelium that can stretch and recoil without being damaged. It lines the urinary bladder and allows the bladder to expand to hold urine, and then contract to expel urine. It is not found in the other locations listed.

Quiz 4: The Tissue Level of Organization

Close examination of a healthy organ reveals a lining of several layers of cells.The layers do not contain any blood vessels and one surface of the cells lines the cavity of the organ.This tissue is a type of

Which one of the following is not one of the four main tissue categories?

Dead skin cells are shed in thin sheets because they are held together by "spots" of proteoglycan reinforced by intermediate filaments.Such strong intercellular connections are called

Germinative cells

Characteristics of epithelia include all of the following except

Epithelium is connected to underlying connective tissue by

Functions of epithelia include all of the following except

A type of intercellular junction that stops materials from crossing an epithelium between cells is called a(n)

Epithelial cells exhibit modifications that adapt them for

The junction type that lets neighboring cells exchange small molecules is the

Epithelial cells that are adapted for absorption usually have ________ at their free surface.

A layer of glycoproteins that prevents leakage of materials from connective tissues into epithelia is the

You would find pseudostratified columnar epithelium lining the

Epithelia specialized for providing sensations of smell,taste,sight,equilibrium,and hearing are known as

Which tissue lines the small intestine and the stomach?

The tissue that always has an apical and a basal surface is ________ tissue.

The heart and blood vessels are lined by ________ epithelium.

Examination of a tissue sample reveals groups of cells united by junctional complexes and interlocking membranes.The cells have one free surface and lack blood vessels.The tissue is most likely ________ tissue.

In stratified epithelia adapted to resist mechanical forces,which of the following types of cell-to-cell junctions are especially abundant?

Transitional epithelium is found