Nutrition and transport in plants

Question 1

What is the structure and adaptation of waxy cuticle

Answer 1

Seals up the leaf/waterproof layer prevent excessive water loss/transparent to allow light energy to pass through

Question 2

Epidermal cells

Answer 2

protect the inner leaf cells

Question 3

palisad mesophyll cell

Answer 3

Has numerous chloroplast to trap light energy for photosynthesis

Question 4

spongy mesophyll cells

Answer 4

Irregularly shaped to create intercelluar air spaces for efficient diffusion of gases

Question 5

xylem

Answer 5

Transport water and dissolved mineral salts from the roots to the rest of the plant

Question 6

gurad cells

Answer 6

regulate the openeing of stoma

Question 7

stoma

Answer 7

allow diffusion of gases

Question 8

How are the leaf adapted

Answer 8

the leaves have a regular pattern to ensure that the leave are not blocking and they obtain max amt of light energy

Question 9

how does carbon dioxide enter the plant

Answer 9

The amount of carbon dioxide in the atmosphere is higher than the leaf.So the co2 diffuse from the higher concentration,atmosphere,to the lower concentration,leaf,via the stomata ,into the intercellular air spaces.The surfaces of mesophyll cells are covered with thin film of water to disslove gases.

Question 10

explain photosynthesis

Answer 10

Light energy absorbed by the chlorophyll is converted into chemical energy.They relases glucose and oxygen.
6co2 +6h2o——–>c6h12o6+O2

Question 11

What is photolysis

Answer 11

light energy is used to spilt water molecules into oxygen and hydrogen atoms

Question 12

how does guard cell control the size of the stomata(sunlight)

Answer 12

During theday,light energy is converted to chemical engergy.More glucose is in the cells so the water potential will be lower than the water potential outside the cell.So the water molecules enter the cell via osmosis through a paritally permemable membrane.The cell become turgid and more curved as the cell wall around the stomata pore is thicker than other parts of the cell.So it curves and it opens for diffusion of gases

Question 13

how does guard cell control the size of the stomata(night)

Answer 13

At night there will be no photosynthesis.The glucose stored will be used up for respiration.So the concentration
of glucose will be lower and the water potential in the cell will be higher than the environment.The water molcuese will osmosise fromt he cell into the environement.so the guard cells become flaccid and it stomata closes

Question 14

how does guard cell control the size of the stomata(very sunny day)

Answer 14

When the leaf loses too much water ,the sotmata closes.Excess evaporation of water causes the guard cells to become more flaccid and closes.

Question 15

what is a limiting factor

Answer 15

one that has effects on the results

Question 16

what are the limiting factors

Answer 16

-light intensity
-carbon dioxide
-temperture

Question 17

Explain why the temperature graph will be back a curve up and down

Answer 17

temperature is a enzym-controlled reaction.increasing the temp to the optimum temp will increase the rate of phtotsynthesis.Beyond it ,the enzyme will denature and the rate of photosynthesis decreases as the enzymes are denatured

Question 18

what happens after photosynthesis

Answer 18

glucose
-used for celluar respiration
-converted into sucrose for translocation and excess glucose will be converted into starch
-used to form(glucose+nitrate) amino acids which forms proteins to make new protoplasm
-used to form fats for storage
oxygen
–diffuses out
—used for respiration

Question 19

importance of photosynthesis

Answer 19

—-produces chemical energy for consumers
—provides o2 and removes co2 which is essential for carbon cycle
—-forms energy stored in coal

Question 20

adaptation of xylem

Answer 20

adpt: Has a continuouse lumen with no cross-walls or protoplasm(dead)
func: reduces resistence to water flow through xylem

adpt:Lignin deposits in the inner walls of xylem
func: provides mechanical support to the plant

Question 21

function of Phloem

Answer 21

Transports sucrose and amino acids from leaves to other parts of the element via tanslocation

Question 22

Adaptation of phloem

Answer 22

sieve tube-:
adpt: it has thin cytoplasm and lack most of the organeslles (eg:mitochondria) and it contains pores
func: Allows rapid flow of sucrose and amino acids and it will facilitate bulk flow of sucrose and amino acid

Question 23

function of companion cell

Question 24

def translocation