4.16-4.22

Question 1

The
refers to a collection of protein fibers that provides structural support to the cell
____________
in addition to movement.

Answer 1

Cytoskeleton

Question 2

Microtubules

Answer 2

Serve as
tracks for
internal
cellular transport
- Cila

Question 3

Intermediate filaments

Answer 3

Reinforce cell shape
- outer cella of your skin

Question 4

Microfilaments

Answer 4

Muscle cells

Question 5

Neurons are very long cells that require the movement of substances from one end of the cell to the
other. Which type of cytoskeletal fiber would you expect to find participating in this process?

Answer 5

Y ou would expect them to have a network of microtubles for this transport

Question 6

Compare cilia with flagella.

Answer 6

Both for movement. Cilia = many short hairs, flagella = long whip-like
tail

Question 7

Briefly explain how the plasma membrane is supported both internally by elements of the cytoskeleton and
externally by the Extra Cellular Matrix.

Answer 7

Fibrous proteins help to provide structure intracellularly and extracellularly. For example, collagen
forms a large portion of the ECM, which helps to protect the cell and holds cells together.

Question 8

Which of the following spans a cell’s entire membrane and allows for signaling between the ECM
and cytoskeleton?

Answer 8

Integrins

Question 9

True or false: Gap junctions prevent substances from leaking through cell layers. If false, make it a
correct statement.

Answer 9

False, tight junctions prevent substances from leaking through cell layers.

Question 10

______ are connections between plant cells that allow for the passage of water and nutrients
and communication between plant cells.

Answer 10

Plasmodesmata

Question 11

In biology, the relationship between form and function is critical. Briefly explain how this is
apparent at the level of the cell. Y our answer should include a specific example of how form
follows function in a cell.

Answer 11

Cellular organelles have structures (form) that allow them to perform their function(s) effi ciently. For
example, lysosomes and peroxisomes are membranous sacs that allow for the com
partmentalization of their toxic contents.

Question 12

Use your knowledge of the information contained within this chapter’s “Big Ideas” to answer this
question.
Certain cells of your immune system respond to certain pathogens by engulfing and digesting these
invading cells and/or moving throughout your body tissues. Briefly identify the organelles that are
involved, as well as their functions, during these events.

Answer 12

White blood cells engulf bacteria, lysosomes
digest the bacteria and get rid of them