cell membrane

Question 1

What is the primary function of the cellular membrane?

Answer 1

To protect the cell and regulate the movement of substances in and out.

Question 2

True or False: The cellular membrane is composed primarily of lipids.

Answer 2

True

Question 3

Fill in the blank: The main type of lipid found in the cellular membrane is called __________.

Answer 3

phospholipid

Question 4

What structure do phospholipids form in aqueous environments?

Answer 4

A bilayer

Question 5

What is the role of proteins in the cellular membrane?

Answer 5

To facilitate transport, act as receptors, and provide structural support.

Question 6

Multiple choice: Which of the following is NOT a component of the cellular membrane?
A) Cholesterol
B) Nucleic acids
C) Phospholipids
D) Proteins

Answer 6

B) Nucleic acids

Question 7

What is the term for the movement of substances across the cellular membrane without energy?

Answer 7

Passive transport

Question 8

True or False: Active transport requires energy to move substances against their concentration gradient.

Answer 8

True

Question 9

Fill in the blank: __________ is the process by which a cell engulfs large particles.

Answer 9

Phagocytosis

Question 10

What is the fluid mosaic model?

Answer 10

A model that describes the structure of the cellular membrane as a mosaic of various components that move fluidly.

Question 11

Multiple choice: Which of the following molecules can easily pass through the lipid bilayer?
A) Ions
B) Small nonpolar molecules
C) Large polar molecules
D) Proteins

Answer 11

B) Small nonpolar molecules

Question 12

What is the function of cholesterol in the cellular membrane?

Answer 12

To maintain membrane fluidity and stability.

Question 13

True or False: Glycoproteins are proteins that have carbohydrates attached to them.

Answer 13

True

Question 14

Fill in the blank: The __________ is a selective barrier that allows certain substances to enter or exit the cell.

Answer 14

cell membrane

Question 15

What is the significance of membrane potential?

Answer 15

It is the voltage difference across the membrane that is crucial for cell signaling.

Question 16

Multiple choice: Which type of transport does NOT require a protein channel?
A) Facilitated diffusion
B) Simple diffusion
C) Active transport
D) Osmosis

Answer 16

B) Simple diffusion

Question 17

What is osmosis?

Answer 17

The diffusion of water across a selectively permeable membrane.

Question 18

True or False: Endocytosis involves the expulsion of materials from the cell.

Answer 18

False

Question 19

Fill in the blank: In __________, the cell membrane folds inward to take in substances.

Answer 19

endocytosis

Question 20

What is the role of receptor proteins in the cellular membrane?

Answer 20

To bind signaling molecules and initiate cellular responses.

Question 21

Multiple choice: Which type of transport moves substances from an area of low concentration to an area of high concentration?
A) Passive transport
B) Active transport
C) Diffusion
D) Osmosis

Answer 21

B) Active transport

Question 22

What does the term ‘selectively permeable’ mean?

Answer 22

It means that the membrane allows some substances to pass while blocking others.

Question 23

True or False: The lipid bilayer is hydrophilic on the outside and hydrophobic on the inside.

Answer 23

True

Question 24

Fill in the blank: __________ are membrane proteins that facilitate the passage of ions across the membrane.

Answer 24

Ion channels

Question 25

What is the role of aquaporins?

Answer 25

To facilitate the rapid transport of water across the cell membrane.

Question 26

Multiple choice: Which process describes the movement of molecules down their concentration gradient? A) Active transport B) Facilitated diffusion C) Both A and B D) None of the above

Answer 26

B) Facilitated diffusion

Question 27

What are lipid rafts?

Answer 27

Microdomains within the plasma membrane that are rich in cholesterol and proteins.

Question 28

True or False: Membrane proteins can be integral or peripheral.

Answer 28

True

Question 29

Fill in the blank: A __________ solution has a higher solute concentration compared to the cell.

Answer 29

hypertonic

Question 30

What happens to a cell in a hypotonic solution?

Answer 30

It swells and may burst due to water influx.

Question 31

Multiple choice: Which condition is necessary for facilitated diffusion to occur? A) Energy input B) A concentration gradient C) A membrane potential D) All of the above

Answer 31

B) A concentration gradient

Question 32

What is the primary role of the cell membrane in cell communication?

Answer 32

To receive and transmit signals through receptors.