Ch-3: Movement into and out of cells

Question 1

Define:

Diffusion

Answer 1

Diffusion is the movement of particles from a region of high concentration to a region of low concentration, along the concentration gradient, until the concentration balances in both the regions

Question 2

What is Surface Area to volume ratio?

Answer 2

The bigger a cell is, the smaller it’s surface area to volume ratio is, slowing down the rate at which substances diffuse across it’s surface

Question 3

What is concentration gradient?

Answer 3

The greater the difference in concentration, the faster the movement will occur across it.

Question 4

On which side will more random collisions against the membrane occur?

Answer 4

On the side with the higher concentration, more random collisions against the membrane will occur

Question 5

Define:

Osmosis

Answer 5

Osmosis is the movement of water molecules from a region of high water potential to a region of low water potential across a semi permeable membrane

Question 6

What pressure does water create on plants?

Answer 6

Water creates a turgor pressure on the cell wall of plants

Question 7

Which structure is present in both plant and animal cell?

Answer 7

cell membrane

Question 8

which structure is present in a plant cell and not in animal cell?

Answer 8

chloroplast

Question 9

Which structure of the plant cell carries out photosynthesis?

Answer 9

chloroplast

Question 10

Which part of a liver cell is also present in a plant cell

Answer 10

cell membrane and cytoplasm

Question 11

(True/False):

Vacuoles are present in both plant and animal cells

Answer 11

True

Question 12

(True/False):

Mitochondria are the sites of respiration

Answer 12

True

Question 13

(True/False):

Diffusion rate is lower if the distance travelled is less

Answer 13

False

Question 14

Define:

Active transport

Answer 14

Active transport is the movement of molecules or ions into or out of the cell through the cell membrane, from a region of lower concentration to a region of higher concentration (against the concentration gradient), using energy released during respiration

Question 15

what are the differences between diffusion and active transport

Answer 15

• Difussion

1. Occurs along the concentration gradient
2. High to low concentration
3. no external sources of energy needed

• Active transport

1. Occurs against the concentration gradent
2. Low to high concentration
3. External energy needed