2.9

Question 1

What is photosynthesis

Answer 1

the reaction of carbon dioxide and water and water using energy from light to produce carbohydrates (carbon compounds) and releasing oxygen as a waste product.

Question 2

Where does photosynthesis take place

Answer 2

in chloroplasts

Question 3

What are chloroplasts

Answer 3

tiny organelles in plant or algae cells where photons are captured

Question 4

What is the wavelength of visible light

Answer 4

400 to 700 nanometres,

Question 5

what si the shortest wavelength we can see

Answer 5

violet

Question 6

what is the longest wavelength we can see

Answer 6

red

Question 7

What pigments capture photons in chloroplast

Answer 7

chlorophyll a and b

xanthophyll and carotenoids

Question 8

why does a plant appear green

Answer 8

because the chloroplast pigments capture photons and reflect green light whilst absorbing most of the other wavelengths in the visible light spectrum

Question 9

What colour does xanthophyll reflect

Answer 9

yellow

Question 10

what color does carotenoids reflect

Answer 10

orange

Question 11

What is a chloroplast

Answer 11

the organelle in plants and algae that contains chlorophyll

Question 12

What colors does chlorophyll absorb most effectively

Answer 12

blue and red

Question 13

What is the action spectrum

Answer 13

shows the efficiency of photosynthesis or the rate of photosynthesis achieved over various wavelengths of light from the visible spectrum

Question 14

What is the absorption spectrum

Answer 14

shows which wavelength of visible light is absorbed by a particular photosynthetic pigment such as chlorophyll a or b measure day a spectrometer

Question 15

Draw an action spectrum

Answer 15

look online

Question 16

draw an absorption spectrum

Answer 16

look online

Question 17

What does the action spectrum record overall

Answer 17

the amount of photosynthesis at each wavelength

Question 18

What is photolysis

Answer 18

the splitting of water by light

Question 19

What energy is used to split water molecules

Answer 19

energy in photons

Question 20

What does photolysis generates

Answer 20

hydrogen ions, electrons and oxygen

Question 21

What is the equation of photolysis

Answer 21

2H20 + photons - 4e- + 4H+ + O2

Question 22

What is released as a by product in photolysis

Answer 22

water

Question 23

Where does the hydrogen and ATP go once being generated from photolysis

Answer 23

to the next stage

Question 24

Where does the energy for photolysis come from

Answer 24

light energy absorbed by the chlorophyl from the sun

Question 25

Where does the oxygen we breathe come from

Answer 25

from water used in the photolysis reaction

Question 26

In which process of photoysnthesis is light directly involved

Answer 26

the splitting of water

Question 27

What are the products of photolysis

Answer 27

hydrogen ions and oxygen

Question 28

What does photosynthesis mean

Answer 28

making things from light

Question 29

What is the energy absorbed from light used for in photosynthesis

Answer 29

turns carbon dioxide and water into carbohydrates and other carbon compounds

Question 30

What type of reaction is photosynthesis

Answer 30

an anabolic reaction in which small molecules (carbon dioxide and water) are joined together to form large molecules (sugars)

Question 31

What is the Calvin cycle

Answer 31

the light independent reactions, a cycle of chemical reactions where CO2 is assimilated to make sugars

Question 32

What is the equation for photosynthesis written

Answer 32

Carbon dioxide + water - carbohydrates + oxygen

Question 33

What are the two stages of photosynthesis

Answer 33

light independent reaction - requires light and occurs on the thylakoids of chloroplasts light independent reaction that has no light requirement and takes place in the storm of chloroplasdts

Question 34

Where does photolysis take place

Answer 34

light dependent in the thylakoids of chloroplasts

Question 35

where does carbon fixation produce carbs

Answer 35

in the light independent at the stroma of chloroplasts

Question 36

What are raw materials in photosynthesis

Answer 36

water and carbon dioxide

Question 37

What is needed in photosynthesis to convert carbon dioxide into organic molecules

Answer 37

ATP and hydrogen from the splitting of water

Question 38

What is a limiting factor

Answer 38

a factor that restricts the rate of a reaction when present in a low amount

Question 39

What are limiting factors of photosynthesis

Answer 39

light, carbon dioxide, temperature,

Question 40

Why is light a limiting factor fo photosynthesis

Answer 40

as sun goes up, rate of photosynthesis increases, but at its peak, the chemical reactions of photosynthesis cannot of any faster so any further increase in light does nor increase the rate, results in a plateau draw the diagram

Question 41

What is rate of uptake when looking at light intensity as the limiting factor

Answer 41

uptake of Co2

Question 42

How is carbon dioxide also a limiting rate of photosynthesis

Answer 42

once all the active sites fo the enzymes are occupied, any further increase in carbon dioxide concentration will not increase the rate graph levels off draw the diagram

Question 43

How is temperature a limiting factor

Answer 43

optimum temperatures, goes up and then it denatures it has a max temp draw graph

Question 44

when did photosynthetic organisms appear

Answer 44

around 2700 million years ago

Question 45

when did eukaryotes appear

Answer 45

around 2100 million years ago

Question 46

What organisms contributed to the rise in oxygen concentration during the first 2 billion years of the Earth's existence?

Answer 46

Cyanobacteria

Question 47

Name the process that accounts for the oxygen in the Earth’s atmosphere, oceans and rock depositions over the past 2 billion years.

Answer 47

photosynthesis

Question 48

What is chromatography

Answer 48

a technique used to separate mixtures of substances based on the movement of the different substances on a piece of paper by capillary action

Question 49

What phases take place in chromatography

Answer 49

the mobile phase ( solvent used to develop the chromatogram) and the stationary phase (the paper)

Question 50

What is the Rf

Answer 50

the distance traveld by the sample/ the distance travelled by the solvent

Question 51

What is a retention factor

Answer 51

allows us to see the distance moved by a pigment in comparison to the solvent

Question 52

What is thin layer chromatography

Answer 52

uses the sample principle as paper chromatography, the stationary phase is usually silica gel, aluminum oxide or cellulose instead od paper

Question 53

What is the benefit of thin layer chromatography

Answer 53

gives a better results as well defined and well separated spots are obtained

Question 54

What substance can be used to dissolve pigments in paper chromatography

Answer 54

ethanol

Question 55

The energy absorbed by chlorophyll is used directly for what in plants?

Answer 55

to split water and produce ATP

Question 56

Why is the action spectrum for photosynthesis similar to the absorption spectra of photosynthetic pigments?

Answer 56

Only wavelengths of light absorbed by pigments can be used in photosynthesis.

Question 57

What is the function of the acetone used in paper chromatography to separate photosynthetic pigments?

Answer 57

It dissolves pigments, allowing them to travel up the paper strip.

Question 58

What is the difference between absorption spectrum and action spectrum for photosynthesis?

Answer 58

The action spectrum represents the rate of photosynthesis at each wavelength of light while the absorption spectrum shows the percentage of light absorbed at each wavelength.

Question 59

From which molecule(s) is oxygen released into the air as a product of photosynthesis?

Answer 59

water