Paper 1: Topic 4 Bioenergetics - Respiration (LV) Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Describe respiration

A

An exothermic reaction which is occurring continually inside all living cells (all plant and animal cells)

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

What is the difference between breathing and respiration?

A
  • Breathing is the process of ventilation i.e. inhalation and exhalation
  • Breathing occurs in the lungs and involves the ribcage and the diaphragm
  • Respiration is a series of chemical reactions that are taking place inside every living cell
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the purpose of respiration?

A

To break down glucose to enable energy to be released for other chemical reactions inside the cell

To produce ATP

REMEMBER: energy can’t be produced/made/created

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

Define the term exothermic

A

A chemical reaction which transfers energy into the environment in the form of heat

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

State 3 uses of the energy released by respiration

A
  1. To build larger molecules from smaller molecules e.g. build proteins from amino acids, to build complex carbohydrates from simple sugars, to build lipids from fatty acids and glycerol
  2. To enable muscles to contract and bring about movement
  3. To maintain body temperature in birds and mammals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Write the word equation for aerobic respiration

A

Glucose + oxygen → carbon dioxide + water + ATP

Hint: do not write energy as a product as energy can’t be made or created

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

Give 5 examples of reactions involved in metabolism

A
  1. Respiration
  2. Conversion of glucose to starch, glycogen or cellulose
  3. Production of amino acids from glucose and nitrate ions in plant cells to synthesise new proteins
  4. Breakdown of excess proteins to form urea for excretion
  5. Production of lipids from 3 fatty acids and 1 glycerol
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What happens to the energy transferred in respiration?

A

It is used by the organism for the continual enzyme controlled processes of metabolism that synthesise new molecules

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

State the two different types of respiration

A

Aerobic

Anaerobic

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

Describe aerobic respiration

A

The complete breakdown of glucose in the presence of oxygen to produce ATP, carbon dioxide and water

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

State the useful product of aerobic respiration

A

ATP

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

State the waste products of aerobic respiration

A

Water and carbon dioxide

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

Describe anaerobic respiration in human muscles

A

The incomplete breakdown of glucose in the absence of oxygen to produce ATP and lactic acid

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

State the useful product of anaerobic respiration in muscles

A

ATP

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

State the waste products of anaerobic respiration in muscles

A

Lactic acid

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

Describe anaerobic respiration in plant and yeast cells

A

The incomplete breakdown of glucose in the absence of oxygen to produce ATP, ethanol and carbon dioxide

17
Q

State the useful product of aerobic respiration

A

ATP

18
Q

State the waste products of aerobic respiration

A

Carbon dioxide and water

19
Q

Which form of respiration transfers the most energy?

A

Aerobic respiration

20
Q

What is the term used to describe anaerobic respiration in yeast cells?

A

Alcoholic fermentation

21
Q

What is the economic importance of fermentation?

Hint: think of 2 useful products that can be made from fermentation

A

It is used in the manufacturing of bread and alcoholic drinks (e.g. beer, wine)

22
Q

Describe 5 changes that occur in the body during exercise

A
  1. Increased heart rate
  2. Increased breathing rate
  3. Increased depth of breathing
  4. Vasodilation of the arterioles at the skin’s surface
  5. Vasconstriction of the arterioles to the digestive system
23
Q

Explain the reasons for the changes observed in the body during exercise

A

To deliver more oxygen to respiring muscle cells

To deliver more glucose to respiring muscle cells

To remove more heat from respiring muscle cells

To remove more lactic acids from contracting muscle cells

To remove more carbon dioxide from respiring muscle cells

Hint you must remember to put the word MORE in to each sentence you write in this answer

24
Q

Describe and explain what happens to the rate of respiration in muscle cells during exercise

A

Description

  • Rate of respiration increases

Explanation:

  • This causes more energy to be transferred to the environment, more lactic acid to be produced and more carbon dioxide to be produced
  • The muscle cells will also have a higher oxygen demand and a higher glucose demand
25
Q

Describe what happens in muscles as a consequence of long periods of vigorous exercise

A

Lactic acid accumulates

An oxygen debt occurs

26
Q

Explain the term oxygen debt

A

The amount of EXTRA oxygen the body requires after exercise to react with the accumulated lactic acid and oxidise it (break it down) to glucose in the liver

27
Q

Explain what happens to the lactic acid produced as a result of anaerobic respiration

A
  • Blood flowing through the muscles transports lactic acid to the liver
  • The liver converts some of the lactic acid back into glucose (for respiration)
  • Some of the lactic acid is broken down to carbon dioxide and water
28
Q

Describe how you can test for the producion of carbon dioxide

A
  • Test*: Bubble the gas through limewater
  • Negative result*: the solution will remain colourless and transparent
  • Positive result*: the solution will turn a milky white colour
29
Q

Write the chemical equation for aerobic respiration

Hint: remember to balance your equation

A

C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP

30
Q

Write the word equation for anaerobic respiration in skeletal muscles

A

Glucose → lactic acid + ATP

31
Q

Write the word equation for anaerobic respiration in yeast or algal cells

A

Glucose → Ethanol + Carbon dioxide + ATP

32
Q

Explain why blood flow to the skeletal muscles increases during exercise

A
  • To deliver more oxygen and more glucose to the skeletal muscles
  • This means more aerbic respiration can take place
  • This means more ATP is produced and more energy is released
  • This means the muscles can contract more

Remember: the delivery of more oxygen also prevents anaerboc respiration occuring and prevents the production of lactic acid

33
Q

Explain why blood flow to the heart muscles (cardiac muscle) increases during exercise

A
  • During exercise the heart rate has to increase
  • This requires more energy to be released from ATP
  • So the heart muscle cells need to carry out more aerobic respiration
  • Increasing the bllod flow to the heart muscles supplies the cells with more oxygen and more glucose
  • This means the heart can contract more frequently AND it can contract more forcefully
  • This then means the blood flows faster to the skeletal muscles
34
Q

What is meant by the term ‘muscle fatigue’

A

When muscles are unable to contract efficiently (due to the accumulation of lactic acid)