Cell transport mechanisms

Question 1

What is passive transport?

Answer 1

Transport that requires no energy from the cell and takes place due to chemical, concentration or electro-chemical gradients

Question 2

What is active transport?

Answer 2

The movement of substances into or out of the cell using ATP

Question 3

What is diffusion?

Answer 3

The movemnet of particles in a liquid or gas down a concentration gradient from an area of high concentration to an area of low concentration

Question 4

What is facilitated diffusion?

Answer 4

Diffusion that takes place through carrier proteins or protein channels

Question 5

What is osmosis?

Answer 5

A form of diffusion that involves the movement of solvent molocules down a concentration gradient through a partially permeable membrane

Question 6

What is endocytosis?

Answer 6

The movement of large molocules into cells through vesicle formation

Question 7

What is exocytosis?

Answer 7

The movement of large molocules out of a cell by vesicle formation

Question 8

Why does diffusion occur?

Answer 8

Molocules move about randomally until they are evenly spread

Question 9

What is an isotonic solution?

Answer 9

A solution where the osmotic concentration of the solutes is the same as that in the cell

Question 10

What is a hypotonic solution?

Answer 10

A solution where the osmotic concentration of solutes is lower than the cell

Question 11

What is a hypertonic solution?

Answer 11

A solution where the osmotic concentration of solutes is higher than the cell

Question 12

How does the cell wall of plants prevent them from bursting?

Answer 12

If the surrounding fluid is hypotonic to the cell, water floods in and the cytoplasm presses on the cell wall and creates hydrostatic pressure. The cell wall keeps it from bursting

Question 13

What is pressure potential?

Answer 13

The inward pressure excerted by the cell wall in plant cells that cancels out the tendency for water to move into the cell

Question 14

What is turgor?

Answer 14

Where the cell is ridged due to being full with water

Question 15

What happens if the fluid surrounding the plant cell is hypotonic?

Answer 15

Water rushes in and causes the cytoplasm to press against the cell wall until the pressure cancels each other out

Question 16

What happens if the fluid surrounding the plant cell is hypertonic?

Answer 16

Water moves out of the cell by osmosis and the membrane begins to pull away from the cell wall

Question 17

What is incipient plasmolysis?

Answer 17

Where water moves out of the cell by osmosis due to being in a hypertonic solution and the membrane moves away from the cell wall as the protoplasm shrinks

Question 18

What is plasmolysis?

Answer 18

Where so much water leaves a plant cell that the cell membrane pulls away from the cell wall

Question 19

What is water potential?

Answer 19

How likely water is to move out of a solution by osmosis

Question 20

What substance has the highest water potential?

Answer 20

Water (0)

Question 21

What is turgor pressure?

Answer 21

A measure of the inward pressure excerted by the cell wall that oposes entry of water by osmosis

Question 22

What is osmotic potential?

Answer 22

The potential of a solution to cause water to move into a cell

Question 23

How can you work out water potential?

Answer 23

Turgor pressure + osmotic potential

Question 24

What happens when turgor pressure and osmotic potential are equal?

Answer 24

The cell is at full turgor and water potential is 0

Question 25

What are carrier proteins?

Answer 25

Proteins that move substances through the membrane in active transport

Question 26

What is phagocytosis?

Answer 26

The active process where a cell engulfs something and encloses it in a vesicle