plant organisation

Question 1

what is the basic structure of a flowering plant?

Answer 1

flowers, stem, leaves, roots

Question 2

how are leaves adapted for photosynthesis?

Answer 2

• large surface area for maximum light absorption
• thin to minimise diffusion distance of carbon dioxide
• chlorophyll trap light energy for photosynthesis
• stomata is site of gas exchange
• network of veins to support the leaf, transport sugars

Question 3

list the structure of parts of the leaf (in order from top to bottom)

Answer 3

waxy cuticle, upper epidermis, palisade mesophyll, spongy mesophyll, lower epidermis, stomata and guard cells, waxy cuticle

Question 4

adaptations of the epidermis

Answer 4

thin and transparent so more light can reach the palisade cells

Question 5

adaptations of the palisade mesophyll

Answer 5

packed with chloroplasts to maximise photosynthesis (absorb as much light as possible)

Question 6

adaptations of waxy cuticle

Answer 6

thin and waterproof- protects the leaf from infection and prevents water loss

Question 7

adaptations of the spongy mesophyll

Answer 7

air spaces for the diffusion of carbon dioxide into the leaf

Question 8

name the two different transport vessels in plants

Answer 8

xylem
phloem

Question 9

what is the function of the xylem?

Answer 9

consists of dead cells and is responsible for the transport of water and minerals up the plant

Question 10

what is the function of the phloem?

Answer 10

transports sugars and amino acids from the leaves to the rest of the plant (this is known as translocation)

Question 11

how are the cells that make up the xylem adapted to their function?

Answer 11

• cells lose end walls so xylem forms a continuous, hollow tube
• lignin gives strength and support to the plant (it is also waterproof!)

Question 12

how are the cells that make up the phloem adapted to their function?

Answer 12

• companion cells attached to sieve tubes, provide them with energy
• sieve tubes have perforated ends (but no nuclei) so each cell is connected

Question 13

does transport in the xylem require energy?

Answer 13

no - passive process

Question 14

does transport in the phloem require energy?

Answer 14

yes - active process

Question 15

what is the function and adaptations of root hair cells?

Answer 15

absorb water and mineral ions
- large surface area
- has lots of mitochondria (provide energy)

Question 16

uses of water for plants

Answer 16

• photosynthesis
• cools leaves (evaporation)
• transports dissolved minerals around the plant