Question 1

Which of the following structures would be located in the dermis of the skin?

Accepted Answer

The dermis of the skin contains nerve endings, connective tissue, sweat glands, and blood vessels, making all of the choices correct.

Question 2

Keratinocytes are pigment cells contained in the epidermis of skin.

Accepted Answer

Keratinocytes are not pigment cells. They are the most common type of cell in the epidermis and produce the protein keratin which provides structural support for the skin. Pigment cells are melanocytes which produce melanin, the pigment responsible for skin color.

Question 3

Which of the following statements about mammalian skin is INCORRECT?

Accepted Answer

The basal lamina is actually a thin layer of extracellular matrix that underlies the epidermis, not the dermis. It separates the epidermis from the dermis, not the dermis from tissues below.

Question 4

An epithelial tissue is defined as a:

Accepted Answer

Epithelial tissue is a collection of cells that line cavities or outside surfaces. It is responsible for protecting and covering the body and its organs, as well as regulating exchange between the external and internal environments.

Question 5

Many scientists use a specific type of mouse cell to coat the surface of petri dishes. These cells form a layer on which other kinds of cells-often of different species-can adhere and grow. The mouse cells used to coat petri dishes are likely:

Accepted Answer

The mouse cells used to coat petri dishes are most likely fibroblasts, as they are commonly used in cell culturing experiments due to their ability to adhere and produce extracellular matrix proteins that provide a supportive environment for other cells to grow. Epidermal cells and melanocytes are more specialized and less commonly used in cell culturing experiments. Hepatocytes are liver cells and are also less commonly used for cell culturing. Microvilli are structures found on the surface of some cells, but are not typically used for coating petri dishes.

Question 6

The area where the epidermis and the dermis meet is highly folded so that the epidermis "fits" into the dermis. What do you think is the function of this highly folded area?

Accepted Answer

The highly folded area between the epidermis and the dermis provides additional support and protection against abrasive stress, which is necessary for the outer layer of the skin under constant physical stress.

Question 7

Which of the following is NOT considered an epithelial tissue?

Accepted Answer

The interior of the brain is not considered an epithelial tissue. It is composed of nervous tissue. The other options are all examples of epithelial tissues.

Question 8

Which of the following structures are responsible for the shape of a cell?

Accepted Answer

The cytoskeleton is responsible for maintaining the shape of the cell. Microvilli, cell junctions, and organelles may play a role in specific functions of the cell, but they do not determine the overall shape of the cell.

Question 9

The extracellular matrix is a network of:

Accepted Answer

The extracellular matrix is a network of proteins and polysaccharides that are located outside the cell and provide support and structure to tissues and organs. Therefore, option B is the correct answer. Option A is incorrect as the proteins and polysaccharides are outside the cell and do not keep organelles in place inside the cell. Option C is incorrect as it refers to proteins that are found in the membrane but not associated with the extracellular matrix, and option D is incorrect as it refers to channel proteins and not the extracellular matrix.

Question 10

A pathologist is carrying out an autopsy. Upon opening the chest cavity, the pathologist sees a thick, fibrous tissue surrounding the heart. This is likely:

Accepted Answer

Thick, fibrous tissue surrounding an organ is characteristic of connective tissue. Neural tissue and muscle tissue would not typically form a fibrous sheath around a heart, and while epithelial cells can form protective layers around organs, they would not typically form a thick fibrous layer.

Question 11

The epidermis contains several layers and receives its nutrients from the dermis by diffusion. Which of the following explains why the outermost layers of the epidermis consist of dead cells?

Accepted Answer

Nutrients can only diffuse through the living cells of the epidermis. Once the outermost layers have formed a barrier to keep out external elements, the cells beyond that layer are cut off from receiving nutrients and ultimately die.

Question 12

Cells differentiate into multiple tissue types because each tissue has its own unique DNA.

Accepted Answer

All cells in an organism have the same DNA, but they differentiate into different tissue types based on gene expression and the signals they receive from their environment.

Question 13

Epithelial tissue is found:

Accepted Answer

Epithelial tissue is found on the outer surface of the body as skin, lining the gastrointestinal tract, lining the lungs, and lining blood vessels. Therefore, all of these choices are correct.

Question 14

Many scientists are working to generate organs in vitro. In some cases, cells are seeded onto a "scaffold" shaped like the desired target organ. Such scaffolds are likely composed of extracellular matrix proteins.

Accepted Answer

This statement is true. Scientists are using scaffolds made of extracellular matrix proteins to generate organs in vitro.

Question 15

Which is the CORRECT order from lesser to greater complexity for the following?

Accepted Answer

The correct order of increasing complexity is cells, tissues, and organs. Cells are the basic building blocks of all living organisms. Tissues are groups of similar cells that work together to perform a specific function. Organs are groups of tissues that work together to perform a specific function. Therefore, the correct order is cells < tissues < organs.

Question 16

Which of the following tissues would you expect NOT to be found in the human heart?

Accepted Answer

All of these tissues are present in the human heart. Muscle tissue forms the bulk of the heart and is responsible for its contraction. Nervous tissue controls the rhythm of the heart. Epithelial tissue lines the blood vessels and heart chambers, and connective tissue provides structure and support.

Question 17

Structures known as microvilli are associated with:

Accepted Answer

Microvilli are small projections on the surface of cells that increase the surface area for nutrient absorption. They are commonly found in cells lining the intestines, where they help increase the absorption of nutrients from food.

Question 18

Which of the following statements about the skin is TRUE?

Accepted Answer

The epidermis is indeed made up of epithelial tissue, which includes multiple layers of cells, while the dermis is primarily composed of connective tissue, which includes collagen and elastin fibers.

Question 19

The basal lamina is:

Accepted Answer

The basal lamina is a specialized form of the extracellular matrix found beneath all epithelial tissues, providing a physical and functional support for the overlying cells. It is not found beneath connective tissues, only in the skin or at tissue junctions, but always beneath epithelial tissues.

Question 20

A researcher is studying a population of cells that are shaped normally, but appear to slide past one another. This is likely the result of mutations in genes encoding:

Accepted Answer

Components of cell junctions are crucial for the adhesion and communication between cells. Mutations in genes encoding these components can disrupt cell adhesion, causing cells to slide past one another.

Quiz 10: Cell and Tissue Architecture: Cytoskeleton, Cell Junctions, and Extracellular Matrix