Exam2 Cell Membrane

Question 1

What is the primary function of the cell membrane?

Answer 1

To protect the cell and regulate what enters and exits.

Question 2

What is the basic structure of the cell membrane?

Answer 2

A phospholipid bilayer.

Question 3

Fill in the blank: The hydrophilic heads of phospholipids face _____.

Answer 3

outward, toward the water.

Question 4

What is the role of cholesterol in the cell membrane?

Answer 4

To maintain membrane fluidity.

Question 5

What term describes the selective permeability of the cell membrane?

Answer 5

Fluid mosaic model.

Question 6

True or False: Carbohydrates on the cell membrane play a role in cell recognition.

Answer 6

True

Question 7

What is the process by which molecules move across the membrane without energy?

Answer 7

Passive transport.

Question 8

Fill in the blank: Active transport requires _____ to move substances against their concentration gradient.

Answer 8

energy (ATP).

Question 9

What is endocytosis?

Answer 9

The process by which cells take in substances by engulfing them.

Question 10

What is exocytosis?

Answer 10

The process by which cells expel materials in vesicles.

Question 11

Multiple Choice: Which type of transport does NOT require energy? A) Active transport B) Facilitated diffusion C) Osmosis D) Both B and C

Answer 11

D) Both B and C

Question 12

What is osmosis?

Answer 12

The diffusion of water across a selectively permeable membrane.

Question 13

True or False: Ion channels are a type of integral protein that facilitates the passive transport of ions.

Answer 13

True

Question 14

What are glycoproteins?

Answer 14

Proteins with carbohydrate chains attached that are involved in cell recognition.

Question 15

Fill in the blank: The cell membrane is described as a _____ because of its flexible nature.

Answer 15

fluid structure.

Question 16

What is the significance of the term ‘mosaic’ in the fluid mosaic model?

Answer 16

It refers to the patchwork of diverse protein molecules embedded in the phospholipid bilayer.

Question 17

Multiple Choice: Which of the following molecules can easily pass through the lipid bilayer? A) Water B) Glucose C) Ions D) Proteins

Answer 17

A) Water

Question 18

What role do aquaporins play in the cell membrane?

Answer 18

They facilitate the transport of water molecules.

Question 19

True or False: The fluid mosaic model was proposed in the 1970s.

Answer 19

True

Question 20

What is the difference between diffusion and facilitated diffusion?

Answer 20

Diffusion does not require a protein, while facilitated diffusion does.

Question 21

Fill in the blank: The movement of solute from an area of high concentration to an area of low concentration is called _____

Answer 21

diffusion.

Question 22

What is a concentration gradient?

Answer 22

A difference in the concentration of a substance across a space.

Question 23

Multiple Choice: Which type of solution causes a cell to swell? A) Isotonic B) Hypertonic C) Hypotonic

Answer 23

C) Hypotonic

Question 24

What is the primary component of the cell membrane?

Answer 24

Phospholipids.

Question 25

True or False: The cell membrane is rigid and does not change shape.

Answer 25

False

Question 26

What is the role of peripheral proteins in the cell membrane?

Answer 26

To provide structural support and assist in signaling.

Question 27

Fill in the blank: The _____ is a protective barrier that separates the interior of the cell from the external environment.

Answer 27

cell membrane.

Question 28

What does the term 'selectively permeable' mean?

Answer 28

It allows certain substances to pass while blocking others.

Question 29

Multiple Choice: Which of the following is a type of passive transport? A) Phagocytosis B) Pinocytosis C) Simple diffusion D) All of the above

Answer 29

C) Simple diffusion

Question 30

What is the role of membrane potential?

Answer 30

To create a voltage difference across the membrane, affecting cell signaling.

Question 31

True or False: Lipid-soluble substances can easily pass through the cell membrane.

Answer 31

True

Question 32

What is a receptor protein?

Answer 32

A protein that binds to specific molecules (ligands) and initiates a cellular response.

Question 33

Fill in the blank: The _____ model describes the arrangement of molecules within the cell membrane.

Answer 33

fluid mosaic.

Question 34

What role do steroids play in the cell membrane?

Answer 34

They help to regulate fluidity and stability.

Question 35

Multiple Choice: Which type of transport moves substances down their concentration gradient? A) Active transport B) Passive transport C) Both A and B

Answer 35

B) Passive transport

Question 36

What is the function of the cytoskeleton in relation to the cell membrane?

Answer 36

It provides structural support and helps maintain cell shape.

Question 37

True or False: All cells have a cell membrane.

Answer 37

True

Question 38

What is the role of signal transduction in the cell membrane?

Answer 38

To relay signals from the outside of the cell to the inside.

Question 39

Fill in the blank: The _____ is the outer boundary of the cell.

Answer 39

cell membrane.

Question 40

What is the significance of membrane fluidity?

Answer 40

It allows for the movement and function of proteins and lipids within the membrane.

Question 41

What is the role of membrane carbohydrates?

Answer 41

They play a key role in cell-cell recognition and communication.