Paper 2 Bio

Question 1

Equation for photosynthesis

Answer 1

Carbon Dioxide + Water = Glucose + Oxygen

Question 2

Root hair cell structure and adaptation

Answer 2

. Takes up water by osmosis and takes mineral ions

. Large surface area means more water can be absorbed

Question 3

Xylem Cells structure and adaptation

Answer 3

. Transports water and mineral ions up the plants from the roots to the shoots
. A chemical called lignin is present causing cells to die
. Xylem has dead cells

Question 4

Phloem cells structure and adaptation

Answer 4

. Carries the products of photosynthesis to all parts of the plant
. Cell walls of each cell form structures called sieve plants when they break down, allowing the movement of substances from cell to cell

Question 5

Guard Cells

Answer 5

. They close and open the stomata

. Thin outer walls and thick inner walls

Question 6

Transpiration

Answer 6

The loss of water vapour from the leaves and stems of the plant

Question 7

Translocation

Answer 7

. The movement of food substances made in the leaves up or down the phloem

Question 8

Chlorophyll

Answer 8

Chlorophyll is green meaning the most light possible is absorbed

Question 9

Large surface area on plants

Answer 9

More light can be absorbed at once increasing the rate of photosynthesis

Question 10

Thinness in a leaf

Answer 10

Carbon dioxide only has a short distance to enter the leaf and oxygen has a short distance to diffuse out

Question 11

Auxins and uses

Answer 11

A growth hormone that moves to the shaded side of the plant and causes the stem to grow towards the light
USES
. Weed Killers
. Rooting powders

Question 12

Gibberellins and uses

Answer 12

Used in germination for fruits and flowers
USES
. They allow fruits to grow heavier and larger increasing yield
. Faster rate of growth

Question 13

Ethene and uses

Answer 13

Controls ripening used in the food industry
USES
. Reduces waste as more food is made to become sold
. Fruits are picked when it is not ripe

Question 14

Type 1 Diabetes

Answer 14

The pancreas cannot produce enough insulin

Question 15

Type 2 diabetes

Answer 15

The body cells no longer respond to insulin

Question 16

Factors affecting the rate of diffusion

Answer 16

Surface Area = More space for particles to move through resulting in a faster rate of diffusion
Temperature = The greater movement in particles meaning more collisions therefore a faster rate of diffusion

Question 17

Rate of Diffusion Calculation

Answer 17

Surface Area x Concentration difference / Thickness of membrane

Question 18

Cardiac Output Calculation

Answer 18

Stroke volume x Heart Rate

Question 19

Investigating the rate of respiration on living organisms

Answer 19

1. Pick a small organism that you would like to measure the rate of respiration
2. Place 5cm cubed of a soda lime into a test tube
3. Plc

Question 20

Food security and factors affecting

Answer 20

Having enough food to feed the population
. Birth rate and human population increase
. Climate change affecting food

Question 21

Maintaining biodiversity

Answer 21

. Breeding programs

. Reduction of deforestation

Question 22

Factors affecting rate of decomposition

Answer 22

. Temperature - Increases rate of decay
. Water - Respiration
. Oxygen - Respire