Brainscape's Knowledge GenomeTM

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


See full index

Biology Year 13 > Energy For Biological Processes > Flashcards

Energy For Biological Processes Flashcards

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

Define photosynthesis and respiration

A

Photosynthesis: the process by which plants harness light to produce complex organic molecules from CO2 and H2O

Respiration: breakdown of complex organic molecules to produce ATP

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

What is the purpose, reactants, products of photosynthesis

A

Purpose: conversion of light energy to chemical energy in organic molecules, 6CO2+6H2O—->C6H12O6+6O2

Reactants: CO2+ H2O

Products: glucose and oxygen

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

What is the type of reaction, ATP production, use of coenzymes for photosynthesis

A

ToR:Endothermic

ATP production: produced in light-dependent stage and used in light independent stage

Use of coenzymes: NADP Carries H atoms between the 2 stages of photosynthesis

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

What is the purpose, reactants, products of respiration

A

Purpose: conversion of chemical energy in organic molecules to chemical energy in ATP C6H12O6+6O2—>6CO2+6H2O

Reactants: glucose and oxygen

Products: CO2 and H2O

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

What is the type of reaction, ATP production and use of coenzymes for respiration

A

ToR: exothermic

ATP production: an end product

Coenzymes: NAD and FAD carry H atoms to electron transport chain

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

Describe the steps of chemiosmosis

A

1: electrons are raised to a higher energy level (ie excited electrons)

2: the high energy electrons pass along an electron transport chain

3: energy is released as the electrons are passed to lower energy levels

4: the energy is used to pump H+ ions across a membrane

5: a proton gradient is established across the membrane

6: protons move down the concentration gradient through channel proteins linked to ATP synthase

7: the flow of protons provides kinetic energy to enable ATP synthesis by ATP synthase

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

For chemiosmosis in photosynthesis:
Where do high energy electrons come from, where is location of ETC, what is name given to ATP production

A

Light absorbed by chlorophyll

Thylakoid membrane (in chloroplasts)

Photophosphorylation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

For chemiosmosis in respiration:
Where do high energy electrons come from, where is location of ETC, what is name given to ATP production

A

Electrons are released from chemical bonds in glucose

Inner mitochondrial membranes

Oxidative phosphorylation

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

What are grana

A

Singular (granum), are flattened membrane compartments (thylakoids), which are sites of light-dependent stage of photosynthesis

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

What is the stroma

A

A fluid-filled matrix, which is the site of the light-independent stage of photosynthesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the adaptations of chloroplast and the purpose

A

Thylakoid membrane are stacked: large SA over which light-dependent reactions can occur

Photosynthetic pigments are organized into photo systems: efficiency of light absorption is maximized

Grana are surrounded by stroma: products of light-dependent reactions (reduced NADP+ATP) can pass directly to enzyme catalyzing the light-independent reactions

Chloroplast contain their own DNA and ribosomes: photosynthetic proteins can be produced inside chloroplasts rather then being imported

The inner chloroplast membrane is embedded with transport proteins and is less permeable than outer membrane: control over which substances that can enter the stroma from cell cytoplasm

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

What are photosystems

A

Light-harvesting complexes of pigments found in thylakoid membranes

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

What are accessory pigments

A

Chlorophyll B and carotenoids (and xanthophylls) absorb photons of light and funnel this energy to a reaction center at the heart of the photo system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are chlorophyll A pigments

A

Located in reaction center, ‘special pair’

Electrons from chlorophyll A are excited and passed to electron acceptors at beginning of ETC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the purpose of the light-dependent stage

A

Light energy is absorbed and enables ATP production

Hydrogen from water is used to reduce NADP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the Light- dependent stage of photosynthesis

A

1: electrons from reaction center in photosystem II are excited

2: the excited electrons are passed along an ETC (and ATP is produced)

3: the electrons from photolysis replace those lost from photosystem II

4: electrons from reaction center in photosystem I are excited

5: more ATP is produced via a second ETC

6: the electrons that left photosystem II replace those lost from photosystem I

7: the electrons from photosystem I and H+ ions from photolysis of water combine to reduce NADP

17
Q

Describe the Calvin cycle

A

1: enzyme RuBisCo catalyses the reaction between RuBP and CO2 to produce two molecules of GP

2: ATP and NADPH are used to reduce GP to TP

3: 1 in every 6 TP used to make glucose, the rest continue the cycle by adding ATP to produce RUBP

18
Q

What are the uses of triose phosphate (TP)

A

Can be converted into:
6-Carbon sugars (eg glucose and fructose)

Fructose and glucose can react to produce disaccharide sucrose

Glucose molecules can react together to form polysaccharides such as amylose, amylopectin and cellulose

A single TP molecule can be converted into glycerol

TP can act as the starting point for the synthesis of amino acids

19
Q

How does light affect photosynethic rate

A

Light intensity determines the rate at which ATP and reduced NADP are produced in the light dependent reactions, can cause a build up of GP

20
Q

How does CO2 concentration affect photosynthetic rates

A

Low CO2 concentrations slow the rate of GP formation

21
Q

How does temperature affect photosynthetic rates

A

Low temperatures limit the kinetic energy of molecules involved in photosynthetic reactions. High temps can cause enzymes such as RuBisCo to denature

22
Q

State 3 similarities between the processes of photosynthesis and respiration (3 marks)

A

Use of ETC

Use of consented (eg NaD in respiration and NADP in photosynthesis)

Some of same intermediates formed (eg GP)

Starting materials are regenerated in both

Both use chemiosmosis to produce ATP

23
Q

Describe the energy conversions and transfers that occur between light and being absorbed by chlorophyll in plant leaves and heat being radiated form organisms (3 marks)

A

Light energy (photons) converter to chemical energy in organic molecules in photosynthesis

Respiration converts chemical energy in organic molecules into chemical energy in inorganic molecules (ATP)

Movement of H+ ions drives ATP production via chemiosmosis

Chemical energy is converted to thermal energy via metabolic reactions

24
Q

State 2 differences between chemiosmosis in respiration and photosynthesis (2 marks)

A

Excited electrons have different origins (ie light absorption in photosynthesis, organic reactions in respiration)

Locations differ (thylakoid in membranes in photosynthesis, inner mitochondrial membranes in respiration)

25
Q

Describe how a proton gradient is established across a thylakoid membrane during photosynthesis

A

Excited electrons are passed along ETC

Energy is released as electrons are passed to lower energy levels

Energy is used to pump protons ; from the storms to the thylakoid space/lumen

26
Q

Name 2 useful molecules that can be produced from TP and describe one way in which a plant can use each molecule (4marks)

A

Glycerol

Triglycerides/ phospholipids/plasma membrane production

Glucose/ fructose

Respiratory substrates, polysaccharides formation

Amino acids

Protein/enzyme formation

27
Q

Explain why the Calvin cycle will stop after a plant has been placed in the dark for a period of time (2marks)

A

ATP and NADPH are both produced in light dependent reactions

Both molecules required for reactions in the Calvin cycle

28
Q

Suggest 3 reasons why plants cannot use the ATP produced in the light independent stage of photosynthesis as their only source of ATP (3 marks)

A

Photosynthesis only occurs in the light

The rate of production is insufficient to supply the plant with the concentration of ATP required

Some plant cells lack chloroplast and would be unable to generate ATP

29
Q

Suggest why temperature changes have a greater impact on the rate of light-independent reactions than light dependent state of photosynthesis (2 marks)

A

Temperature affects the rate of enzyme activity

More enzymes are involved in the light-independent stage than the light-dependent stage

30
Q

Where does light independent and dependent stages of photosynthesis occur

A

Independent: thylakoids of chloroplasts

Dependent: stroma of chloroplasts

31
Q

What happens in the electron transfer chain for photosynthesis

A

Electrons released from chlorophyll move down carrier proteins embedded in thylakoid membrane

Biology Year 13 (4 decks)

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