photosynthesis

Question 1

equation for photosynthesis?

Answer 1

carbon dioxide + water-> glucose + oxygen

Question 2

chemical equation for photosynthesis?

Answer 2

6CO2 + 6H2O -> C6H12O6 + 6O2

Question 3

where does it happen within a cell?

Answer 3

chloroplasts

Question 4

what do chloroplasts contain?

Answer 4

chlorophyll

Question 5

what are some limiting factor of Photosynthesis?

Answer 5

sunlight, carbon dioxide, temperature

Question 6

what does carbon dioxide do to increase photosynthesis?

Answer 6

it controls availability of carbon in leaves

Question 7

what does sunlight do to increase photosynthesis?

Answer 7

as there is more energy for photosynthesis, so controls rate of reaction

Question 8

what does temperature do to increase photosynthesis?

Answer 8

it controls kinetic energy, so more kinetic energy, means more successful collisions between substrate and active site of enzymes, and so rate of photosynthesis increases

if temp too hot, enzyme denatures

Question 9

name all the levels of a leaf?

Answer 9

cuticle, upper epidermis, palisade mesophyll, spongy mesophyll, lower epidermis

Question 10

what is the vascular bundle?

Answer 10

where the xylem and phloem are

Question 11

what is the role of the waxy cuticle?

Answer 11

reduces water loss by evaporation and acts as a barrier to diseases

Question 12

what is the role of the upper epidermis?

Answer 12

transparent to allow maximum light through

Question 13

what is the role of the palisade mesophyll?

Answer 13

as tightly packed and has many chloroplasts its the site of photosynthesis,

Question 14

what is the role of the spongy mesophyll?

Answer 14

as has rounded cells and many air pockets, its the site of gas exchange to absorb CO2 and release oxygen and glucose

Question 15

role of lower epidermis?

Answer 15

doesn’t have one

Question 16

where are guard cells and stomata in a leaf?

Answer 16

lower epidermis

Question 17

what is the role of guard cells?

Answer 17

to control the opening and closing of the stomata

Question 18

role of stomata?

Answer 18

to allow CO2 in and oxygen out

Question 19

where is the vascular bundle located?

Answer 19

in both mesophylls

Question 20

role of xylem?

Answer 20

transport mineral ions and water around the leaf

Question 21

role of phloem?

Answer 21

transport sugars and amino acids around the leaf

Question 22

adaptations of a leaf?

Answer 22

has a large surface area and the leaf is thin

Question 23

what is the role of a large surface area?

Answer 23

to maximise light entering the leaf

Question 24

what is the role of a thin leaf?

Answer 24

allows light to penetrate through to larger numbers if cells

Question 25

how do mineral ions enter a plant?

Answer 25

by active transport through the root hairs

Question 26

what are the 2 main mineral ions a plant needs?

Answer 26

nitrates and magnesium

Question 27

why are nitrates needed in a plant?

Answer 27

mainly for growth and to make amino acids and proteins

Question 28

why is magnesium needed in a plant?

Answer 28

for growth and to make chlorophyll

Question 29

what converts light energy to chemical energy?

Answer 29

chlorophyll in chloroplasts

Question 30

describe the investigation for evolution of oxygen from a water plant?

Answer 30

-set up a beaker containing water and pondweed and a lamp with a ruler
-change the distance of the lamp by 10cm intervals
-use the same species of pondweed
-repeat 3x
-measure by counting number of bubbles produced per minute (oxygen)
-keep the same lamp, temperature of water, size of plant, same environment

Question 31

describe an investigation of the production of starch from a leaf?

Answer 31

-place leaf in boiling water for 1 minute
-wear safety goggles
-cover leaf in ethanol and place in water bath for 1 minute to dissolve all chlorophyll
-rinse in cold water
-place leaf on white tile
-cover in iodine
-blue/black =positive, yellow=negative

Question 32

describe the variegated leaf practical?

Answer 32

-place 5 leaves with different black tape on
-place 1 leaf in a sealed flask of sodium hydroxide as it absorbs CO2
-place in dark for 24 hours to destarch
-then place in light for 24 hours
-perform starch test
-then obtain results