Plants

Question 1

Pathway of water through the stem into the surrounding air?

Answer 1

Water taken up by the xylem
Towards the leaves
Evapo

Question 2

Structure of xylem?

Answer 2

Hollow or dead tubes that extend from root to leaf
No protoplasm
To able to conduct water and ions
Lignified walls for strength

Question 3

Significance of distribution of chloroplasts in the process of photosynthesis?

Answer 3

In palisade and spongy
More in palisade
Since it’s near to leaf surface, hence maximum absorption of sunlight
Rapid rate of photosynthesis

None in epidermis
In guard cells,
Chloroplasts control the stomata
As stomata need ATP which is provided by photosynthesis, hence the presence of chloroplasts

Question 4

Significance of stomata and mesophyll cell in gas exchange?

Answer 4

CO2 and O2
In photosynthesis, CO2 is diffused in and O2 is diffused out
In respiration, CO2 is diffused out and O2 is diffused in
Stomata allows transpiration
Mesophyll cells have moist surface and large surface area

Question 5

Arrangement of xylem and phloem in roots?

Answer 5

Centre of root
One xylem
Unpaired

Question 6

Arrangement of xylem and phloem in stem?

Answer 6

Around edge
Many xylem
Phloem and xylem paired
Later of cambium in-between

Question 7

Effect of temperature on rate of transpiration?

Answer 7

Rate increases
Increased evaporation from surface of mesophyll cells
Diffusion gradient where inside plant there is more water
Molecules move faster due to kinetic energy

Question 8

Effect of light intensity on rate of transpiration?

Answer 8

Rate increases
More stomata open
Open wider
Increased surface area for water loss

Question 9

Effect of humidity on rate of transpiration?

Answer 9

Rate decreases
Outside higher concentration of water

Question 10

Importance of transpiration to a plant?

Answer 10

Create transpiration pull
Brings water and salts front the roots to the leaves
For photosynthesis
Also cools the plant