Cells

Question 1

How are palisade leaf cells specialised?

Answer 1

1) Packed with chloroplasts for photosynthesis. 2) Crammed at the top of leaf (nearer light). 3) Tall shape, so more surface area for absorbing more CO2.

Question 2

How are guard cells adapted ?

Answer 2

1) when inflated with water it becomes turgid and opens stomata. 2) When deflated it becomes flaccid and closes stomata. 3) sensitive to light so close at night to save water.

Question 3

what is differentiation?

Answer 3

when a cell changes to become specialised for a function.

Question 4

what is a tissue?

Answer 4

group of similar cells working together to perform a particular function.

Question 5

what is an organ?

Answer 5

group of different tissues working together to perform a certain job.

Question 6

organ system

Answer 6

group of organs working together to perform particular function.

Question 7

examples of organ system

Answer 7

digestive, respiratory, reproductive.

Question 8

photosynthesis

Answer 8

Carbon dioxide + water -> glucose + oxygen

Question 9

green substance in plants is..

Answer 9

chlorophyll

Question 10

plant structure (starting from top)

Answer 10

waxy layer, upper epidermis, palisade layer, spongy mesophyll, lower epidermis with guard cells.

Question 11

limiting factors of photosynthesis..

Answer 11

1) light intensity 2) CO2 concentration 3) Temperature

Question 12

why is light a limiting factor?

Answer 12

as light intensity is raised, rate of photosynthesis increases until certain point. it will make no difference so there is another limiting factor.

Question 13

why CO2 is a limiting factor?

Answer 13

increases rate of photosynthesis up to a point. there is another limiting factor.

Question 14

why temperature is a limiting factor?

Answer 14

increase in temp. means faster rate of photosynthesis until it gets too hot. enzymes get damaged at 45°C

Question 15

how plants use glucose…

Answer 15

1) respiration 2) making cell walls(convert to cellulose) 3) stored as starch. 4) making proteins.

Question 16

how to use quadrat

Answer 16

1) place at random point 2) count organisms and repeat.

Question 17

workout population size of organism in a sample area..

Answer 17

mean number of of organisms per square metre x total area of the habitat. e.g. 32 flowers x 300 square metres of area.

Question 18

to increase reliability

Answer 18

larger sample size, use many quadrats as possible on sample area.

Question 19

to increase validity

Answer 19

use more random samples.

Question 20

what is habitat?

Answer 20

a place where an organism lives

Question 21

uses of enzymes in industry..

Answer 21

biological detergents, baby foods, fructose syrup.

Question 22

advantages of enzymes in industry..

Answer 22

1) catalyse reaction you want
2) use lower temperatures, save s energy
3) do not need replacement, work for long time.

Question 23

disadvantages of enzymes in industry..

Answer 23

1) people develop allergies
2) get denatured by small changes, temperature.
3) expensive to produce.