Membranes

Question 1

What is the primary function of cell membranes?

Answer 1

To control the movement of substances in and out of the cell.

Question 2

True or False: Diffusion requires energy input.

Answer 2

False

Question 3

Fill in the blank: The movement of water across a selectively permeable membrane is called __________.

Answer 3

osmosis

Question 4

What is facilitated diffusion?

Answer 4

The process of passive transport of molecules across a cell membrane via specific transmembrane proteins.

Question 5

Which type of transport requires energy from ATP?

Answer 5

Active transport

Question 6

Multiple Choice: Which of the following substances is most likely to diffuse freely across the cell membrane? A) Ions B) Glucose C) Oxygen D) Proteins

Answer 6

C) Oxygen

Question 7

Define active transport.

Answer 7

The movement of molecules across a membrane from a region of lower concentration to a region of higher concentration, using energy.

Question 8

True or False: All molecules can pass through the lipid bilayer of a cell membrane easily.

Answer 8

False

Question 9

What role do channel proteins play in facilitated diffusion?

Answer 9

They provide a pathway for specific molecules to pass through the membrane.

Question 10

Fill in the blank: The concentration gradient is the difference in __________ of a substance between two regions.

Answer 10

concentration

Question 11

What is bulk transport?

Answer 11

The process by which large particles or volumes of substances are transported across the cell membrane.

Question 12

Multiple Choice: Which of the following is an example of active transport? A) Osmosis B) Sodium-potassium pump C) Simple diffusion D) Facilitated diffusion

Answer 12

B) Sodium-potassium pump

Question 13

What happens to a cell placed in a hypertonic solution?

Answer 13

It shrinks due to water moving out of the cell.

Question 14

True or False: Facilitated diffusion can occur against a concentration gradient.

Answer 14

False

Question 15

What is the function of transport proteins in membranes?

Answer 15

To assist in the movement of substances across the cell membrane.

Question 16

Fill in the blank: The process of engulfing large particles by the cell is called __________.

Answer 16

phagocytosis

Question 17

What is osmosis primarily concerned with?

Answer 17

The movement of water molecules.

Question 18

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

Answer 18

A) Simple diffusion

Question 19

Explain the term ‘selectively permeable’.

Answer 19

A property of cell membranes that allows some substances to pass while restricting others.

Question 20

What effect does temperature have on the rate of diffusion?

Answer 20

Higher temperatures increase the rate of diffusion.

Question 21

True or False: Active transport can occur against a concentration gradient.

Answer 21

True

Question 22

What is the primary energy source for active transport?

Answer 22

ATP (adenosine triphosphate)

Question 23

Fill in the blank: The process of releasing substances from a cell is called __________.

Answer 23

exocytosis

Question 24

Multiple Choice: Which of the following is NOT a factor affecting the rate of diffusion? A) Temperature B) Concentration Gradient C) Size of Molecule D) Color of Molecule

Answer 24

D) Color of Molecule

Question 25

What is the main difference between diffusion and facilitated diffusion?

Answer 25

Facilitated diffusion requires specific channel or carrier proteins, while diffusion does not.

Question 26

What is osmosis?

Answer 26

Osmosis is the movement of water molecules across a selectively permeable membrane from an area of lower solute concentration to an area of higher solute concentration.

Question 27

True or False: Osmosis requires energy to occur.

Answer 27

False

Question 28

Fill in the blank: Osmosis is a type of __________ transport.

Answer 28

passive

Question 29

What is a selectively permeable membrane?

Answer 29

A selectively permeable membrane is a barrier that allows certain substances to pass through while blocking others.

Question 30

In which direction does water move during osmosis?

Answer 30

Water moves from an area of lower solute concentration to an area of higher solute concentration.

Question 31

What is osmotic pressure?

Answer 31

Osmotic pressure is the pressure required to prevent the flow of water across a semipermeable membrane via osmosis.

Question 32

Multiple Choice: Which of the following solutions is hypertonic to a cell? A) 0.9% NaCl B) 3% NaCl C) Distilled water

Answer 32

B) 3% NaCl

Question 33

What happens to a cell placed in a hypotonic solution?

Answer 33

The cell will swell and may burst due to the influx of water.

Question 34

True or False: In osmosis, solute molecules move across the membrane.

Answer 34

False

Question 35

What is the main driving force behind osmosis?

Answer 35

The concentration gradient of solutes across the membrane.

Question 36

What is the primary function of cell signaling?

Answer 36

To transmit information between cells to coordinate their functions.

Question 37

True or False: All cell signaling occurs through direct contact between cells.

Answer 37

False.

Question 38

Fill in the blank: __________ signaling involves the release of signaling molecules that affect nearby cells.

Answer 38

Paracrine

Question 39

What type of signaling uses hormones to communicate over long distances?

Answer 39

Endocrine signaling.

Question 40

Which of the following is NOT a type of cell signaling? A) Autocrine B) Paracrine C) Cytokine D) Endocrine

Answer 40

C) Cytokine.

Question 41

Short answer: Name one common signaling molecule involved in cell signaling.

Answer 41

Cytokines, hormones, or neurotransmitters.

Question 42

What is the role of receptors in cell signaling?

Answer 42

To bind signaling molecules and initiate a cellular response.

Question 43

True or False: Signal transduction pathways can amplify the strength of a signal.

Answer 43

True.

Question 44

Multiple choice: Which of the following processes is primarily involved in cell communication? A) Photosynthesis B) Signal transduction C) Respiration D) Fermentation

Answer 44

B) Signal transduction.

Question 45

Fill in the blank: The process by which a signaling molecule triggers a response in a target cell is known as __________.

Answer 45

Signal transduction.