3. Movement Into And Out Of The Cell

Question 1

Describe diffusion

Answer 1

net movement of particles from a region of their higher
concentration to a region of their lower concentration (i.e. down a concentration gradient), as a result of their random movement

Question 2

Where does energy for diffusion come from

Answer 2

Kinetic energy of random movement of molecules and ions

Question 3

Substance move into and out of the cells by

Answer 3

Diffusion through cell membrane

Question 4

Describe the importance of diffusion of gases and
solutes in living organisms

Answer 4

Get rid of their waste products
Obtain substances they require to live
Gas exchange for respiration

Question 5

Role of water as a solvent

Answer 5

Substances dissolved in water can be easily transported
Toxic substance in excess can dissolve in water to be excreted in wine
Ensures metabolic reactions can occur

Question 6

Describe osmosis

Answer 6

the net movement of
water molecules from a region of higher water
potential (dilute solution) to a region of lower
water potential (concentrated solution), through
a partially permeable membrane

Question 7

Importance of osmosis in plant tissues

Answer 7

Plants are supported by the pressure of the water. inside the cell pressing outwards on the cell wall

Question 8

Describe osmosis in cells

Answer 8

Hypotonic - water will enter
A- lysed; swell and burst
P- turgid; high turgor pressure
Hypertonic - water will leave
A - suriveled;shrinks
P-flaccid J plasmolysed
Cell membranes separates from cell wall
Cell contents Shrink

Question 9

Describe active transport

Answer 9

movement of
particles through a cell membrane from a region
of lower concentration to a region of higher
concentration (i.e. against a concentration
gradient), using energy from respiration

Question 10

Explain the importance of active transport

Answer 10

Process for movement of molecules or ions across membranes, including ion uptake by root hair

Question 11

Describe protein carriers

Answer 11

Move molecules or ions across A melubrane during active transport

Question 12

,describe nitrate ion uptake

Answer 12

. Nitrate ion enters the protein carries
Carrie protein changes shape with energy from respiration
Nitrate ion is pushed out because of change in shape

Question 13

How is active transport different

Answer 13

-Requires energy
Goes against the concentration gradient
Diffusion doesn’t require a membrane

Question 14

Name one animal cell organelle that would occur in large numbers in a metabolically active cell

Answer 14

Mitochondria or ribosomes

Question 15

Which is the best adapted for diffusion
Ileum, atria, bronchioles or capillaries

Answer 15

Ileum - microvilli

Question 16

Describe the role of carrier proteins in active transport

Answer 16

The substance combines with the lawyer protein which changes Shad using energy from respiration to rapport the substance across the membrane