Plat Tissues

Question 1

Palisade mesophyll

Answer 1

Plant tissue which is adapted to absorb light for photosynthesis and is located in the upper layer of a leaf

Question 2

Structure of palisade mesophyll

Answer 2

• Packed with chloroplast - contains chlorophyll to absorb sunlight for photosynthesis
• are column shaped and arranged closely together
• towards the upper surface of the leaf

Question 3

Spongy mesophyll

Answer 3

Plant tissue which is packed loosely for efficient gas exchange

Question 4

Structure of spongy mesophyll for function

Answer 4

• covered by a thin layer of water - gasses dissolve in this water as they move in and out of cells
• when the play is photosynthesizing during the day these features allow CO2 to diffuse into the spongy mesophyll and O2 to diffuse out

Question 5

Meristem

Answer 5

Found out the tips of roots and shoots where unspecialised stem cells undergo a type of cell division called mitosis

Question 6

Xylem

Answer 6

The xylem transports water and minerals from the roosts up the plant stem and into the leaves

Question 7

Phloem

Answer 7

Moves food substances that the plant has produced by photosynthesis - sugars and amino acids. Transport in the phloem is both up and down. Consists of living cells.

Question 8

Sieve tube

Answer 8

Specialized for transport and have no nuclei. Has a perforated end so its cytoplasm connects one cell to the next

Question 9

Companion cells

Answer 9

Help the phloem transport substances by providing energy.

Question 10

Epidermis

Answer 10

Protective tissue that covers the entire surface of the plant

Question 11

Structure of xylem for its function

Answer 11

Vessels lose their end walls so the xylem forms a continuous hollow tube
Becomes strengthened by lignin. The cells are no longer alive. Lignin gives strength and support to plant.

Question 12

Stomata

Answer 12

Tiny holes found in epidermis of the leaf. Control water loss and gas exchange by opening and closing.

Question 13

Guard cells

Answer 13

Surrounds stomata. In bright light they take in water my osmosis and become turgid and plump. In low light they lose water and become flaccid causing stomata to close.
Guard cells are adapted to their function by allowing gas exchange and controlling water loss within the leaf

Question 14

Root hair cells

Answer 14

A specialized cell that increases the surface area of the root epidermis to improve the uptake of water and minerals

Question 15

How are root hair cells adapted

Answer 15

They have a large surface area to increase the rate of absorption.
They contain lots of mitochondria which releases energy from glucose during respiration to provide the energy needed for active transport