Mr Afriyie Gas exchange - Photosynthesis flashcards

Question 1

Upper Epidermis

Answer 1

A thin, single layer of cells located at the top of the leaf, directly beneath the cuticle. Transparent layer that allows light to pass through.

Question 2

Cuticle

Answer 2

A thin, waxy, transparent layer covering the upper surface of the leaf. Waxy layer that prevents water loss.

Question 3

Palisade Mesophyll

Answer 3

A layer of elongated, closely packed cells found below the upper epidermis. It is elongated to increase surface area for maximum light absorption. It has lots of chloroplasts to absorb light.

Question 4

Chloroplasts

Answer 4

Absorb light for phostosynthesis found within the palisade mesophyll.

Question 5

Spongy Mesophyll

Answer 5

A layer of loosely arranged, round cells with many air spaces, located below the palisade mesophyll. It has lots of air spaces for the diffusion of gases.

Question 6

Vascular Tissue

Answer 6

A bundle of tube-like structures (xylem and phloem) often found in the center of the leaf sections ->** (xylem + phloem).

Question 7

Xylem

Answer 7

Part of the vascular tissue, usually larger tubes towards the top of the bundle. It transports water.

Question 8

Phloem

Answer 8

Part of the vascular tissue, usually smaller tubes located below the xylem in the bundle. It transports food substances e.g. sucrose.

Question 9

Air Space

Answer 9

Gaps between the spongy mesophyll cells, appearing as empty spaces.

Question 10

Lower Epidermis

Answer 10

A thin, single layer of cells on the underside of the leaf.

Question 11

Stomata

Answer 11

Tiny openings in the lower epidermis, usually surrounded by guard cells.

Question 12

Gas exchange

Answer 12

refers to the diffusion of carbon dioxide (CO2) into the leaf and oxygen diffusing out of the leaf.

Question 13

Guard cell

Answer 13

It opens and closes to allow gases to diffuse through the stomata.