difussion,osmosis,active transport and enzymes

Question 1

What is diffusion?

Answer 1

The process by which molecules spread from areas of high concentration to areas of low concentration.

Question 2

True or False: Diffusion requires energy input.

Answer 2

False

Question 3

Fill in the blank: Diffusion occurs in __________ solutions.

Answer 3

liquid and gas

Question 4

What factors affect the rate of diffusion?

Answer 4

Temperature, concentration gradient, and particle size.

Question 5

What is osmosis?

Answer 5

The movement of water molecules through a selectively permeable membrane from an area of low solute concentration to an area of high solute concentration.

Question 6

True or False: Osmosis only involves the movement of solutes.

Answer 6

False

Question 7

Fill in the blank: Osmosis is crucial for __________ in living organisms.

Answer 7

cellular function

Question 8

What is the main difference between diffusion and osmosis?

Answer 8

Diffusion involves all types of molecules, while osmosis specifically refers to the movement of water.

Question 9

What is active transport?

Answer 9

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

Question 10

True or False: Active transport does not require energy.

Answer 10

False

Question 11

What is the role of ATP in active transport?

Answer 11

ATP provides the energy required for the transport of molecules against their concentration gradient.

Question 12

Fill in the blank: Active transport is essential for maintaining __________ in cells.

Answer 12

homeostasis

Question 13

What are transport proteins?

Answer 13

Proteins that assist in the movement of substances across a cell membrane.

Question 14

What is the primary function of enzymes?

Answer 14

To act as catalysts that speed up chemical reactions in biological processes.

Question 15

True or False: Enzymes can be used up in a reaction.

Answer 15

False

Question 16

Fill in the blank: Enzymes lower the __________ energy of a reaction.

Answer 16

activation

Question 17

What is the enzyme-substrate complex?

Answer 17

The temporary complex formed when an enzyme binds to its substrate.

Question 18

What factors can affect enzyme activity?

Answer 18

Temperature, pH, and substrate concentration.

Question 19

What is denaturation in terms of enzymes?

Answer 19

The process where an enzyme loses its three-dimensional structure and, consequently, its activity.

Question 20

Fill in the blank: The __________ model describes how enzymes and substrates interact.

Answer 20

lock and key

Question 21

How do inhibitors affect enzyme activity?

Answer 21

Inhibitors decrease or prevent enzyme activity by binding to the enzyme.

Question 22

What is competitive inhibition?

Answer 22

When an inhibitor competes with the substrate for the active site of the enzyme.

Question 23

What is non-competitive inhibition?

Answer 23

When an inhibitor binds to an enzyme at a site other than the active site, reducing its activity.

Question 24

Fill in the blank: Enzymes are __________ specific, meaning they only catalyze specific reactions.

Answer 24

substrate

Question 25

What is the role of coenzymes?

Answer 25

Coenzymes are organic molecules that assist enzymes in catalyzing reactions.

Question 26

Give an example of a coenzyme.

Answer 26

NAD+ (Nicotinamide adenine dinucleotide)

Question 27

What is the significance of enzyme concentration in a reaction?

Answer 27

Increasing enzyme concentration can increase the rate of reaction, provided that substrate is available.

Question 28

What is substrate concentration's effect on enzyme activity?

Answer 28

Increasing substrate concentration increases the rate of reaction to a point, after which the rate levels off.

Question 29

What is the term for the energy required to initiate a chemical reaction?

Answer 29

Activation energy

Question 30

What happens to enzyme activity at extreme temperatures?

Answer 30

Enzyme activity typically decreases and may lead to denaturation.

Question 31

Fill in the blank: The __________ is the region on an enzyme where the substrate binds.

Answer 31

active site

Question 32

What is the importance of pH for enzymes?

Answer 32

Each enzyme has an optimal pH at which its activity is maximized.

Question 33

True or False: All enzymes function best at neutral pH.

Answer 33

False

Question 34

What is the role of temperature in enzyme reactions?

Answer 34

Temperature affects the kinetic energy of molecules, influencing the rate of enzyme-catalyzed reactions.

Question 35

What is facilitated diffusion?

Answer 35

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

Question 36

True or False: Facilitated diffusion requires energy.

Answer 36

False

Question 37

What is the difference between simple diffusion and facilitated diffusion?

Answer 37

Simple diffusion occurs directly through the membrane, while facilitated diffusion requires specific transport proteins.

Question 38

What is the role of aquaporins?

Answer 38

Aquaporins are channel proteins that facilitate the transport of water across cell membranes.

Question 39

Fill in the blank: The __________ gradient drives the process of diffusion.

Answer 39

concentration

Question 40

What is the main purpose of the sodium-potassium pump?

Answer 40

To maintain the electrochemical gradient across the plasma membrane of the cell.

Question 41

What is endocytosis?

Answer 41

The process by which cells internalize substances by engulfing them in a membrane.

Question 42

What is exocytosis?

Answer 42

The process by which cells expel substances from the interior to the exterior via vesicles.

Question 43

Fill in the blank: __________ transport requires energy, while passive transport does not.

Answer 43

Active

Question 44

What is the primary energy molecule used in cellular processes?

Answer 44

ATP (Adenosine triphosphate)

Question 45

True or False: Enzymes can function in both forward and reverse reactions.

Answer 45

True

Question 46

What is the role of feedback inhibition in metabolic pathways?

Answer 46

To regulate enzyme activity and prevent the overproduction of substances.

Question 47

Fill in the blank: The __________ is the maximum rate of an enzyme-catalyzed reaction at a given substrate concentration.

Answer 47

Vmax

Question 48

What are allosteric enzymes?

Answer 48

Enzymes that have multiple binding sites and can be regulated by molecules that bind to sites other than the active site.