6.2 & 6.3 photosynthesis

Question 1

describe the process of photosynthesis

Answer 1

sunlight falls on chloroplast > energy of light is absorbed by chlorophyll > chlorophyll molecule releases the energy > released energy makes carbon dioxide and water, with the help of enzymes inside chloroplast > glucose that is made contains energy that was originally in sunlight (light energy is transferred to chemical energy)

Question 2

what is the balanced equation for photosynthesis?

Answer 2

6CO2+6H2O→C6H12O6+6O2 (sunlight & chlorophyll >)

Question 3

what is the name of the close-fitting cells that cover the top and bottom of the leaves?

Answer 3

epidermis

Question 4

what structures of the leaves contain chloroplasts?

Answer 4

the mesophyll layer and the guard cells

Question 5

what do the xylem tubes carry?

Answer 5

water

Question 6

what do the phloem tubes carry?

Answer 6

sucrose and other substances (food)

Question 7

what is the top layer of the mesophyll layer called?

Answer 7

palisade mesophyll

Question 8

what is the bottom layer of the mesophyll layer called?

Answer 8

spongy mesophyll

Question 9

how do leaves expose themselves to as much air as possible?

Answer 9

the leaf is held out into the air by the stem and the leaf stalk (petiole), so its large surface area expose it to as much air as possible

Question 10

which cells need carbon dioxide?

Answer 10

the mesophyll cells

Question 11

how does air diffuse inside the cells?

Answer 11

behind each stoma is an air space which connects up with other air spaces between the spongy mesophyll cells; it can then diffuse through the cell wall and cell membrane of each cell, then into the chloroplasts

Question 12

how is water obtained?

Answer 12

absorbed from root hairs > carried to the leaf by xylem vessels > travels from the xylem vessels to the mesophyll cells by osmosis

Question 13

what helps the sun easily penetrate through the leaves?

Answer 13

the position of the leaves; its broad and flat surfaces; the arrangement of the leaves and the chloroplasts; transparent epidermis cells with no chloroplasts

Question 14

how do chloroplasts position themselves? and in strong sunlight?

Answer 14

they lie broadside on in the palisade cells (to keep a few cell walls as possible between sunlight and the chloroplasts); in strong sunlight, they are arranged end on (to reduce the amount of light absorbed)

Question 15

how do chlorophyll expose themselves to more sunlight

Answer 15

they arrange themselves on flat membranes