Bios Chapter 10

Which answer choice correctly lists components found in the extracellular matrix of animals?

Collagen, laminin, and elastin

Which structures are responsible for the shape of a cell during cell division?

Cytoskeleton

Which one of the statements about intracellular transport is true?

Myosin moves substances along microfilaments

Some cytoskeletal elements are more permanent that others. Which component of the cytoskeleton are dynamic structures?

-Microfilaments -Microtubules

Which of the statements about intracellular transport are true?

-Microfilaments facilitate cellular movement -Microtubules facilitate cellular movement

Epithelial tissue is found:

-On the outer surface of the body -Lining the gastrointestinal tract -Lining the lungs -Lining blood vessels

Myosin motor proteins use the energy of ATP to:

-Carry vesicles along microfilaments within a cell -Cause changes in cell shape -Shorten muscle fibers

Cancer can be characterized by:

-Cells with an enhanced ability to adhere to proteins in the basal lamina -A mass of rapidly dividing cells called a tumor -Metastasized tumor cells that leave the tumor and invade distant parts of the body

Evidence that cytoskeletal elements have ancient origins comes from the:

-Presence of cytoskeletal elements in both eukaryotes and prokaryotes -Observation that both prokaryotes and eukaryotes use cytoskeletal elements to assist cell division -Sequence similarities of cytoskeletal elements when comparing distantly related organisms -Ability to form functional hybrid microfilaments from actin monomers taken from distantly related organisms

How does extracellular matrix affect a cell that it surrounds?

-The cell's shapes depends in part on the structure and composition of the extracellular matrix -The genes that the cell expresses depend in part on the types of proteins in the extracellular matrix

The most likely reason(s) a metastatic tumor cell might lose its connection to the basal lamina would be:

A change in the integrin proteins from the cell's surface

A researcher is assessing the expression of a specific protein in cells. The protein appears as a "web" in the cytoplasm of cells. The protein is likely:

A component of the cytoskeleton

In order for a tumor cell to metastasize, which of the changes would you expect to happen?

A decrease in cadherin expression and an increase of integrin expression

Epidermolysis bullosa is a set of rare genetic disorders that is caused by:

A keratin gene that disrupts intermediate filaments, weakening connections between epidermal cell layers

Which of the statements about mammalian skin is incorrect?

A specialized form of extracellular matrix, called the basal lamina, underlies the dermis and separates it from tissues below it

Which one of the choices matches a type of cell junction with its proper cytoskeletal element and cell adhesion molecule?

Aderens junctions, microfilament, cadherin

A decrease in cell-cell adhesion was caused by the introduction of an experimental substance that compromised the structure integrity of the tissue. Which type of cell junction would most likely be affected by this treatment given that the treatment caused by a decrease in the strength of cell-cell adhesion

Adheren junctions

Which cytoskeletal elements is/are associated with supporting the movement of materials inside the cell?

Both microtubules and microfilaments

Which one of the choices is a characteristic shared by integrins and cadherins

Both proteins have a cytoplasmic domain connecred to the cytoskeleton

Kinesin motor proteins use the energy of ATP to:

Carry vesicles along a microtubule within a cell in a minus-to-plus direction

Many scientists use a specific type of mouse cell to coat the surface of petri dishes with extracellular matrix proteins. This coating forms a later on which other kinds of cells, often of different species, can adhere and grow. The mouse cells used to coat petri dishes are likely:

Fibroblasts

The dermis of mammalian skin, including that of humans, contains a large amount of extracellular matrix proteins, including collagen and elastin. As a person ages, the amount of elastin in the dermis declines. Which of the cell types is likely to be the cause of this change in the dermis of the skin?

Fibroblasts

Which one of the choices matches a type of cell junction with the correct cytoskeletal element and cell adhesion molecules?

Hemidesmosome, intermediate filament, integrin

Where would you find a cell adhesion molecule?

In a cell junction

Structures known as microvilli are associated with:

Increased surface area for nutrient absorption

Which of the statements about integrins is correct?

Integrins indirectly connect microfilaments with the extracellular matrix

Which of the cytoskeletal elements contribute to the structural integrity and strength of epithelia tissue in animals

Intermediate filaments and microfilaments and microtubules

Which statement about intracellular transport is true?

Kinesin and dynein move substances along microtubules

Kinesin is a motor protein found attaches to:

Microtubules

Which is the correct decreasing order of cytoskeletal elements from largest filament diameter to smallest filament diameter

Microtubules -> intermediate filaments -> microfilaments

Which of the choices enable(s) the movement of cells

Microtubules and microfilaments

Microtubules and microfilaments are said to be "dynamic" elements of the cytoskeleton. In this case, "dynamic" means that:

Microtubules and microfilaments are assembled, disassembled, and then reassembled again in a regulated manner

The cytoskeleton of animal cells includes:

Microtubules, microfilaments and intermediate filaments

Which of the choices correctly lists the sequence in which the plant cell wall is synthesized?

Middle lamella -> primary cell wall -> Secondary cell wall

Macrophage cells undergo a process called phagocytosis in which material is brought into a cell in the form of membrane vesicles and then transported along microtubules toward the cell center. Assuming that the centrosome is near the cell center, you can predict that these vesicles are moving to the _____ end of microtubules using the motor protein _____.

Minus end; dynein

Why are the ends of microfilaments and microtubules called "plus ends" and "minus ends"

Monomers are added more quickly to one end (the "plus end") than they are to the other end (the "minus" end)

Microfilaments increase in length:

More quickly at one end than the other

The internal cytoskeletal structure of cilia grows out from a structure called a basal body located near the base of the cilia. Based on this information, where would you predict the plus end of the microtubules to be located?

Near the tip of the cilia (or flagella)

In nerve cells, the centrosome is located near the nucleus. Vesicles move from near the nucleus to the end of long extemsions (axons) along microtubules. Based on these two facts, it is possible to conclude that these vesicles are moving in the ________ direction on the microtubule using the motor protein _________

Plus end; kinesin

Suppose there is a mutation in a laminin-binding integrin gene that causes a loss of function in the cytoplasmic domains of the integrin. Which one of the outcomes would you expect to observe as a result of this mutation?

The strength of tissues would decrease because the integrin could no longer associate with microfilaments

Suppose there is a mutation in a laminin-binding integrin gene that causes a loss of function in the cytoplasmic domains of the integrin. Which one of the outcomes would you expect to observe as a result to this mutation?

The strength of tissues would decrease because the integrin could no longer associate with microfilaments

A patient in a physician's office has a deep cut, and as it is being stitched up, a sample of tissue is taken for testing. Analysis of the tissue reveals it has few cells, surrounded by a large amount of extracellular matrix proteins with some blood vessels, sweat glands, and nerve cells. What kind of tissue is this?

The tissue is most likely dermis, and should also have some fibroblasts, but few keratinocytes and melanocytes

Gap junctions and plasmodesmata have what feature in common?

They both allow direct transport of materials between cells