Brainscape's Knowledge GenomeTM

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


See full index

IB HL BIOLOGY > Cell Respiration > Flashcards

Cell Respiration Flashcards

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

What is cell respiration?

A

The controlled release of energy from organic compounds to produce ATP

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

What is respiration catalysed by?

A

Enzymes

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

Which cells perform cell respiration?

A

ALL cells

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

What are some ways cells use energy?

A

Active transport
Translation
Vesicle transport

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

How is ATP produced?

A

A phosphate group is linked to ADP. Energy is needed to carry out this reaction.

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

Where do plants and animals gain their energy from?

A

Animals- breakdown of organic compounds in the food

Plants-organic substances made by photosynthesis

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

What are the advantages of ATP as an energy supply?

A
  1. The energy is released very fast by splitting ATP into ADP and inorganic phosphate
  2. It can diffuse to all parts of the cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Where does aerobic respiration take place in eukaryotes?

A

In the mitochondria

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

What does aerobic respiration require?

A

Oxygen

Glucose/carbohydrates or lipids or amino acids

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

How is glucose converted in the cytoplasm?

A

Glucose is first converted to pyruvate in the cytoplasm which produces 2 pyruvate molecules and pyruvate is transported to mitochondria. Carbon dioxide and water are produced.

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

What is the yield of ATP in aerobic respiration?

A

36 ATP -2 ATP in glycolysis and 34 in mitochondria

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

Describe anaerobic respiration

A

In cytoplasm. Breakdown of ONLY glucose without use of oxygen. It gives a small yield of ATP- 2 molecules of ATP.

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

What are the products of anaerobic respiration in humans and yeast?

A

Humans- lactic acid

Yeast/plants: Carbon dioxide and ethanol

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

When is anaerobic respiration useful?

A
  1. A short but rapid burst of ATP is needed
  2. Oxygen supplies run out in cells
  3. In oxygen- deficient environments
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is oxygen debt?

A

The demand of oxygen that builds up during anaerobic respiration

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

What happens to lactate after vigorous exercise?

A

The lactate is broken down aerobically in the liver

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

What is yeast used for?

A

Bread making

Brewing and the biofuel industries

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

Describe the process of bread making.

A

Yeast is mixed mixed with dough which contains sugar for cell respiration. The dough is kept warm(enzyme function). Yeast rapidly uses up all the oxygen and then respires anaerobically producing ethanol and carbon dioxide. Ethanol evaporates and the carbon dioxide makes the dough rise.

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

Describe the process of brewing and biofuel industry

A

Yeast produces ethanol by fermentation. Plants are processed with enzymes to digest the starch and cellulose to sugars. Yeast is cultured inside large fermenters in a liquid containing sugars but no oxygen. Yeast respires anaerobically and produces ethanol and CO2. Ethanol is collected in a liquid. When ethanol conc reaches a certain point it is removed because then it become too toxic.

In biofuels, the produced ethanol is purified by distillation to improve its combustion.

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

What is a respirometer?

A

A device set up to measure respiration rates

21
Q

Outline the respirometer

A
  1. Organism respires aerobically so it uses o2 and gives of co2
  2. Released co2 is absorbed by alkali- soda lime
  3. Volume of air inside the respirometer decreases
  4. Pressure decreases making the coloured liquid move towards organism
  5. Volume of oxygen consumed equals the increase in volume of coloured liquid.
22
Q

Give the equation for ATP hydrolysis

A

ATP–> ADP + Pi

23
Q

What are many metabolic reactions?

A

Endergonic-absorb energy so they do not proceed spontaneously unless coupled with an exergonic reaction that releases more energy.

24
Q

List the 4 processes that occur during aerobic cell respiration

A
  1. Glycolysis
  2. Link reaction
  3. Krebs cycle
  4. Oxidative phosphorylation
25
Q

What is oxidation and reduction?

A

Oxidation- lose of electrons/ hydrogen atoms

Reduction- gain of electrons/ hydrogen atoms

26
Q

What happens to the hydrogen that is removed from the substrates during oxidation?

A

Hydrogen is accepted by a hydrogen carrier which is reduced. Also known as electron carreirs as they gain electrons and protons

27
Q

Which is the most common hydrogen carrier?

A

NAD

28
Q

How is reduction of NAD shown?

A

NAD+ 2H–> reduced NAD

29
Q

List the hydrogen carriers

A

FAD and NAD

30
Q

What is phosphorylation?

A

The addition of a phosphate group to an organic molecule

31
Q

Where is the phosphate group transfered from?

A

ATP

32
Q

What does phosphorylation cause?

A

Causes the molecule to be less stable and therefore more likely to react in the next step of the metabolic pathway.

33
Q

What is glycolyis?

A

A metabolic pathway in which a hexose sugar is partially oxidised into two pyruvates and a small amount of ATP that takes place in the cytoplasm in both aerobic and anaerobic repsiration.

34
Q

List the main stages of glycolysis

A
  1. Phosphorylation of hexose
  2. Lysis of hexose biphosphate
    Oxidation of triose phosphate and ATP formation
35
Q

Describe Glycolysis

A

Phosphorylation of hexose- 2 phosphate groups are added to a molecule to form hexose biphosphate. 2 ATP molecules provide the phosphate groups.
Lysis of hexose biphosphate- One hexose biphosphate molecule is split to form molecules of triose phosphate
Oxidation of triose phosphate and ATP formation- 2 hydrogen atoms are removed from each triose molecule to form pyruvate.

Hydrogen ions are accepted by NAD, forming two reduced NAD per glucose molecule. The end energy released from the oxidation of each triose phosphate is used to convert two ADP molecules into two ATP.

36
Q

What is the net yield of ATP in glycolysis?

A

Two ATP molecules are used per glucose molecule, four are produced so there is a net yield of two ATP molecules.

37
Q

Where does Link reaction take place?

A

link reaction takes place in the matrix of the mitochondrion.

38
Q

Describe the link reaction.

A

Hydrogen and carbon dioxide are removed from pyruvate.
Hydrogen is accepted by NAD to form reduced NAD.
There is then the removal of hydrogen and carbon dioxide which is oxidative decarboxylation.
The product is an acetyl group which reacts with CoA to form acetyl coenzyme.
It then enters Krebs cycle

39
Q

What is the Krebs cycle?

A

A cycle of reactions catalysed by enzymes in the matrix of the mitochondrion.

40
Q

What are the main reactions of the Krebs cycle?

A
  1. An acetyl group from acetyl CoA is transferred to a C4 compound to form a C6 compound.
  2. Two CO2 molecules are removed in two decarboxylation reactions to form first C5 compound and then a C4 compound. CO2 is excreted as a waste product.
  3. Hydrogen is removed in 4 oxidation reactions. In three of the oxidations the hydrogen is accepted by NAD and one in FAD. The oxidations release energy which is then stored in hydrogen carriers to make ATP later.
  4. In one reaction ATP is produced directly- substrate- level phosphorylation.
  5. C4 compound is reformed.
41
Q

Outline briefly ATP production by oxidative phosphorylation.

A
  1. The energy released by oxidation reactions is carried to the cristae of the mitochondrion by reduced NAD and reduced FAD.
  2. Electrons from reduced NAD and reduced FAD pass along the electron transport chain and release their energy.
  3. This energy is used to pump protons from the matrix into the intermembrane space. A proton conc gradient is formed- store of PE
  4. ATP synthase located in the inner mitochondrial membrane, allows protons to diffuse back into the matrix and uses the energy that protons release to produce ATP.
42
Q

Describe in detail the electron transport chain

A
  1. The electron transport chain is a series of electron carriers located in the inner membrane including the cristae.
  2. Reduced NAD donate 2 electrons to teh first carrier. The electrons come from earlier oxidation reactions and bring energy too.
  3. As electrons pass from one carrier to the next they release energy
  4. Some electron carriers act as proton pumps and use this energy to pump protons against the concentration gradient from the matrix into the intermembrane space.
  5. A proton conc gradient is formed across the inner mitochondrial membrane which is a store of PE.
  6. Reduced FAD also feeds electrons in to the electron transport chain, but at a later stage than reduced NAD.
  7. At the end, the electrons are given to the oxygen and this happens in the matrix. Oxygen also accepts protons and forms water
43
Q

Where is the only place oxygen is used up ?

A

The use of oxygen as the terminal electron acceptor in the electron transport chain.

44
Q

Describe the process of oxidative phosphorylation.

A
  1. The electron transport chain has built a proton conc gradient across the inner mitochondrial membrane.
  2. The protons diffuse back into the matrix releasing energy
  3. Protons diffuse through ATP synthase which is located in the inner mitochondrial membrane
  4. ATP synthase uses the energy that the protons release as they diffuse to produce ATP
  5. ATP synthase catalyses the phosphorylation of ADP into ATP.
  6. The coupling of ATP synthesis to the electron transport and movement of protons across a membrane is called chemiosmosis.
  7. Since the electrons come from previous oxidation reactions of cell respiration, electron carriers are oxidised and ADP is phosphorylated into ATP- oxidative phosphorylation.
  8. 32 ATP molecules are produced so 36 ATP molecules are produced in aerobic respiration.
45
Q

Describe the adaptations of mitochondria

A
  1. Outer mitochondrial membrane- separates the contents of the mitochondrion from the rest of the cell
  2. Inner mitochondrial membrane- contains electron transport chains for generating a proton gradient and ATP synthase- Has cristae to increase the surface area for oxidative phosphorylation
  3. Cristae- Increase the sa for oxidative phosphorylation
  4. Space between outer and inner membrane is narrow as to build a steep proton concentration gradient quickly
  5. Matrix- fluid inside the mitochondrion containing enzymes for Krebs
  6. 70S ribosomes and naked circular DNA - found in matrix and the proteins in the mitochondrion are coded by genes. (synthesises proteins)
46
Q

What is an electron tomography?

A

A technique for obtaining detailed 3- dimensional images of sub-cellular structures

47
Q

What has electron tomography allows us to do?

A

To obtain 3D images of the interior active mitochondria

48
Q

What did the electron tomography help us see better?

A

The cristae originate at narrow openings and that membranes are dynamic and the shape and volume of the cristae change when a mitochondrion is active.

IB HL BIOLOGY (25 decks)

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