Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

biology assessmet. > photosynthesis : ) > Flashcards

photosynthesis : ) Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

what biological processes do plants require energy for ?

A
  • photosynthesis
  • active transport
  • DNA replication
  • proteinsynthesis
  • cell division
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

which biological processes do animals require energy for?

A
  • cell division
  • protein synthesis
  • DNA replication.
  • active transport.
  • muscle contraction
  • thermoregulation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is a coenzyme?

A

an organic molecule that takes part in reactions + is changed by them. They usually work by transferring a chemical group from one molecule to another.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

which coenzyme is involved in photosynthesis?

A

NADP
NADP transfers Hydrogen from one molecule to another.
its reduced in LDR and oxidised in LIDR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

which coenzyme is involved in respiration?

A

NAD
FAD
Coenzyme A

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what is a light harvesting system

A

accessory pigments that surround the reaction centers + the harvest + transfer light to them to boost the energy available for photoexcitation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the 2 types of p. pigment?

A 
primary pigments like chlorophyll a
accessory pigments (ie chlorophyll b, xanthophylls, carotenoids)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what do accessory pigments do?

A

absorb light at wavelengths that primary pigments cannot , it then convert them + send them to reaction center

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

why do most plants appear green?

A

most plants have ALOT of chlorophyll a and thus reflect ALOT of green pigment. They absorb all the other colours.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what happens when a pigment absorbs light?

A
  • it will appear black.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

why do some plants fluoresce?

A
  • if too much light is absorbed.

- plants release excess energy by emitting light as a longer wavelength –> fluorecent light

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is the wavelength of chlorophyll a in PS2 and PS1 ?

A

PS2 –> 682

PS1 –> 700

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what does an absorption spectrum show?

A
  • the % of light absorbed by pigments from each wavelength of light.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what does an action spectrum show?

A
  • the rate of photosynthesis for each wavelength of light. The rate will NOT be the same at every wavelength.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what is the role of different pigments in the photosynthetic process?

A
  • different pigments absorb different wavelengths of light in the antenna complex which is the light harvesting photosystem
  • energy is then passed on to chlorophyll a in the reaction center.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

where does the light dependant reaction occur?

A

the grana

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what does the LDR produce?

A

ATP

NADPH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

where does the light independent reaction occur?

A

the stroma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what does the LIDR produce?

A

glucose (using products of the LDR)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what is non cyclic photophosphorylation?

A

p. synth that involves both PS2 and PS1.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what are the products of non cyclic PP

A

ATP

NADPH

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what is the 1st electron donor in non cyclic PP

A

water (ie photolysis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

which photosystems are involved in Non cyclic PP?

A

PS2 and PS1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what is the last electron acceptor in non cyclic pp

A

NADP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what is cyclic PP?

A

pp that only involves PS1

26
Q

what happens in cyclic PP?

A

the electron is not ejected to reduce NADP, instead it leaves PS1 , passes through the ETC again to move H+ to eventually synthesis a small amount of ATP. , before moving back to PS1 again

27
Q

where do the electrons go to in cyclic pp?

A

PS1, they leave PS1 and comback to PS1

28
Q

what is the 1st electron donor + last electron acceptor in cyclic pp?

A

PS1

PS1

29
Q

which photosystem is involved in cyclic pp?

A

PS1 only

30
Q

how is the grana adapted to function?

A
  • the thylakoids have a large biconcave shape and thus alot more SA for pigments to absorb more light.
  • the grana have photosynthetic pigments that absorb wavelengths of light at diff Wv.
31
Q

how might a leaf be adapted to grow in shady conditions?

A
  • has alot of chlorophyll and chloroplasts to absorb ALOT of light energy to gain energy for electrons in the p.systems.
32
Q

why is green light not used in photosynthesis?

A
  • chlorophyll pigment reflect green light
  • gree light not used in p synth
  • v v little p synth occur
33
Q

what is chemiosis?

A
  • the process of electrons flowing down an ETC and then creating H+ gradient as H+ use energy to diffuse across membrane, all in order to provide proton motive force to synthesis ATP.
34
Q

what are the 3 main conditions that are optimal for photosynthesis in temperate climates?

A

1) high intensity of a certain wavelength
2) temperature of 25C
3) Carbon dioxide at 0.4%

35
Q

what would happen to rate pf photosynthesis if the temperature fell below 10C and why?

A
  • the rate would slow down as the enzymes , ie rubisco become inactive
36
Q

if the T>45C what would happen to stomata + how does this affect rate of p.synthesis.

A
  • stomata will close to reduce the water loss by transpiration
  • this will reduce the rate of photosynthesis as less CO2 can be taken up for the calvin cycle
37
Q

if the T>45C what would happen to thylakoid membranes + how does this affect rate of p.synthesis.

A
  • they will be damaged

- this could reduce the rate of light dependant reactions by reducing the no of sites available for electron transfer.

38
Q

if the T>45C what would happen to chloroplast membranes + how does this affect rate of p.synthesis.

A
  • they membrane surrounding chloroplast would be damaged and thus would cause enzymes such as rubisco to diffuse into the plant cell, reducing the rate of the calvin cycle.
39
Q

if the T>45C what would happen to chlorophyll + how does this affect rate of p.synthesis.

A

this would damage the whole chlorophyll which would reduce the amount of pigment that can absorb light energy, and this would reduce the rate of the LDR

40
Q

what does increasing CO2% from 0.04% in the atm to 0.4% do to p.synthesis rate

A

-increases the rate of the CALVIN CYCLE however, at higher than this and the stomata will start to close.

41
Q

what can TP be used as a starting material for?

A
  • carbohydrates
  • lipids
  • amino acids
42
Q

how are carbohydrates made from TP?

A
  • hexose sugars can be made by joining 2 TP molecules together (bc each one is made from 3c) (if gluc, need 6 turns of the cycle bc only 1C from each 2TP molecules produced) is used to make glucose
43
Q

how can lipids be made from TP + GP molecules?

A

made from using Glycerol which is synthesisded from TP, they are also made from fatty acids made from GP

44
Q

how can amino acids be made from GP?

A
  • some aa can be made from GP
45
Q

How much TP is made from 1 turn of the cycle and how much C atoms is that?
Thus how many turns of the cycle are needed to provide 6 TP?

A

2TP per turn of cycle (ie CO2 used) which produces 6c atoms in total

  • to make 6TP , u need 3 turns (bc 2tp/cycle x 3= 6TP)
46
Q

How many TP molecules are used to regeerate RUBP?

Thus how many per cycle are made to make glucose

A
  • 5TP out of 6 for regenerating ruBp

- thus only 1TP is made to synthesise Glucose (ie 3c)

47
Q

for every 3 turns of the cycle

  • how many TP
  • what is TP used to make
A
  • u get 6TP molecules
  • 5 of which are used to regen ruBP
  • is used to make gluc
48
Q

if u only get 1TP per 3 cycles for glucose how many cycles are needed to produce glucose?

A

6 turns
3 turns x 2 = 6 turns
now u have 2 TP for glucose ( 3c + 3c = 6c hex)

49
Q

how does a low light intensity affect the levels of GP, TP and RUBP?

A
  • low light intensity means that the products produced in the LDR in the grana will be in short supply
  • as a result the levels of TP will decline as GP cant be converted to tP
  • thus RUBP will decline as less TP is available to regenerate it.
  • levels of GP will rise as it is still being made (by CO2 + any RUBP present)
50
Q

how does the temperature affect the level of GP , TP and RUBP?

A
  • ALL the reactions in calvin require enzymes Ie RuBisCO
  • low temps mean that all the reactions of the calvin cycle will be slower as the enzymes involved in the calvin cycle work more slowly.
  • the same effect occurs for too high temps, where the enzymes are denatured and then GP,TP and RUBP levels are low
51
Q

how does [CO2] affect the level of RUBP, GP and TP?

A
  • at low CO2 conc, GP levels are pretty low bc there is little available CO2 to react w/ RUBP to make 6c -> GP>
  • bc low GP, there will be low TP
  • RuBP will rise bc its still being made.
52
Q

give the + and -ve of using CO2 for measuring rate of photosynthesis?

A

+ CO2 is only used in the calvin cycle.

- some CO2 may be the product of respuration and thus may be used in photosythesis

53
Q

give the + and -ve of using O2 to measure the rate of photosynthesis?

A

+ O2 only produced + released in the LDR

- O2 produced may be used for plant respiration

54
Q

briefly describe the apparatus and the method u would use to investigate how temperature affects photosynthesis in Canadian Pondweed.

A
  • we will measure the rate of photosynthesis by looking at vol of O2 prod over time
  • u need a light source, capillary tube, gas syringe.
    1) a test tube w/ pondweed (Elodea) us connected to the capillary tube full of water.
    A source of white light is placed at a specific distance from the pond weed.
    3) the pondweed is left to photosynthesise for a set amount of time - as it does so the O2 released as a product will be collected in the capillary tube.
    4) At the end of the experiment the syringe is used to draw the bubble of O2 gas alongside a rule and the length of the gas bubble is measured –> the vol of the O2 prod = length.
    variables such as time, vol of H2O , size of ELodea, CO2 conc are all kept constant.
    5) the experiment is repeated and the avg length of the gas bubble is calc to make the results more precise.
55
Q

how would u supply a plant in a potomter with additional CO2?

A
  • NaHCO3

sodium hydrogen carbonate.

56
Q

why is not all the O2 produced in a plant collected in a potometer ?

A
  • some is trapped in air spaces

- some is used in respiration /oxidative phosphorluation

57
Q

Some aquatic photosynthetic organisms, for example seaweeds, contain pigments such as fucoxanthin and phycoerythrin, in addition to chlorophyll. These pigments give seaweeds a brown or red colour and are produced in larger quantities in those seaweeds that live in
deeper water.
Suggest why the presence of these pigments is an advantage to seaweeds that live in deeper
water.

A
  • deeper waters have a lower light intensity.
  • these pigments absorb wavelengths of light that are shorter.
  • not all wavelengths will penetrate into deeper water
58
Q

how could u improve the validity of an photosynth experiment that is measuring effect of diff limiting factors?

A
  • cut the discs of leaves to the same size SO the surface areas are the SAME
  • carry out repeats so that a MEAN can be calculated.
59
Q

what happens when green light is exposed to green plants?

A
  • the chlorophyll reflects green light + doesnt absorb it.
  • green light is NOT used in photosynthesis.
  • bc less light absorbed less photolysis will occur + less excitation
60
Q

In order to maximise production, market gardeners often grow plants in glasshouses.
Light conditions can be controlled along with a number of other factors. HOW can factors other than light conditions be controlled to INCREASE the rate of
photosynthesis and MAXIMISE production?
In your answer you should explain why the rate of photosynthesis is affected by the controlled
factors you have discussed

A
  • photosynthesis is controlled by ATP synthase in non/cyclic photophosphorylation and by Rubisco in the calvin cycle.
  • Temperature can be increased w/ heater to increase enzyme activity –> ie produce more ATP via ATP synthase more quickly.
  • CO2 can be increased by burning a fuel. –> increases rate of calvin cycle as more CO2 available to be fixated.

biology assessmet. (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions