B9 Respiration

Question 1

What happens during aerobic respiration?

Answer 1

glucose reacts with oxygen, transfers energy to cells to use for bodily functions

Question 2

What is the chemical equation for aerobic respiration?

Answer 2

C6H12O6 + 6O2 -> 6CO2 + 6H2O

glucose + oxygen -> carbon dioxide + water

Question 3

What type of reaction is an Aerobic reaction?

Answer 3

Exothermic reaction-> transfer energy to the environment

Question 4

Where does aerobic respiration take place?

Answer 4

In the mitochondria

Question 5

What are Mitochondria?

Answer 5

• tiny rod shaped organelle
• found in almost all plant, animal, fungal, algal cells
• folded inner membrane: large SA for enzymes in Aerobic respiration
• number of mitochondria in a cell show how active you are

Question 6

What do organisms use the energy supplied from respiration for?

Answer 6

• Build large molecules from smaller molecules for new cell material (synthesis reactions)
• Break down larger molecules to smaller
• Make muscles contract (heart beat, stomach churn) (animals)
• Constant internal body temp (mammals + birds)
• Move mineral ions (nitrates into root hair cells, convert sugars + nitrates + nutrients into amino acids -> proteins) (Plants)

Question 7

What is Muscle tissue + how does it work?

Answer 7

Made up of protein fibres, contracts when energy is transferred from respiration
- muscle fibres need lots of energy to contract
- contain many mitochondria for aerobic respiration
- contract in big groups to cause moment, allowing other muscles to work
- store glucose as glycogen (converted during exercise)

Question 8

What is the response of the body during exercise?

Answer 8

• many muscles contract harder + faster, need more glucose + oxygen for respiration
• produce increased amounts of CO2, needs to be removed to work effectively

Question 9

When muscular activity increases (during exercise), how does the body change?

Answer 9

• heart rate increases, arteries supplying blood to muscles dilate-> increase rate of oxygen + glucose supply for increased cellular respiration needed and increases removal rate of CO2
• breathing rate increases + deeper breaths, bring more air into lungs, increase oxygen in body + in red blood cells to muscles, removing CO2 more quickly from blood to lungs, breathed out
• glycogen is converted back to glucose, supply cells with fuel for increased cellular respiration-

Question 10

What are the aims of the bodily responses to exercise?

Answer 10

• increase rate of supply of glucose + oxygen to muscles
• increase rate of removal of CO2 from muscles

Question 11

What is Anaerobic respiration?

Answer 11

Respiration without oxygen

• occurs during exercise
• leads to incomplete breakdown of glucose

Question 12

What is the word equation for Anaerobic respiration?

Answer 12

glucose-> lactic acid

Question 13

Why is Anaerobic respiration less efficient than Aerobic respiration?

Answer 13

glucose molecules are not broken down completely-> less energy is transferred

Question 14

What happens if muscles work for a long time?

Answer 14

• become fatigued, don’t efficiently contract
• if there is a lack of oxygen, they will anaerobically respire

Question 15

Why can muscled become fatigued?

Answer 15

• Build up of lactic acid (produced by anaerobic respiration)
• can cause Oxygen Debt

Question 16

How is Lactic acids removed from the body?

Answer 16

• has to be broken down by oxygen, produces CO2 + water
• results in puffing and panting to pay off oxygen debt

Question 17

What is the reaction equation for anaerobic respiration in plants + yeast?

Answer 17

glucose-> ethanol + carbon dioxide

Question 18

What is the name for anaerobic respiration in yeast cells?

Answer 18

Fermentation
- used to make alcohol, bread

Question 19

What is the metabolism of an organism?

Answer 19

the sum of all reactions that take place in a cell or body

Question 20

How is the energy transferred in respiration used by the organism

Answer 20

• heat the environment
• continual enzyme-controlled processes of metabolism that synthesise new molecules

Question 21

What are some examples of metabolic reactions?

Answer 21

• conversion of glucose to starch, glycogen and cellulose
• reactions of respiration
• reactions of photosynthesis
• breakdown of excess proteins in the liver to form urea for excretion in the urine, by the kidneys

Question 22

What is the liver?

Answer 22

a large reddish, brownish organ
- cells grow and regenerate rapidly

Question 23

What are metabolic functions of the liver

Answer 23

• detoxifying poisonous substances (ethanol in alcoholic drinks)
• passing breakdown products into blood-> excreted in urine via kidneys
• breaking down old, worn out blood cells and storing iron until need to synthesise more blood cells

Question 24

How does the body get rid of the lactic acid?

Answer 24

• blood flowing through the muscles transports the lactic acid to the liver
• converted back into glucose
• repays oxygen debt once all the glucose is broken down in aerobic respiration to form CO2 and water

Question 25

What is the Hepatic Vein?

Answer 25

carries blood from liver to the heart (levels of food adjusted)

Question 26

What is the Hepatic Portal Vein?

Answer 26

carries blood containing digested food from intestines to the liver

Question 27

What is the Hepatic Artery?

Answer 27

brings oxygenated blood to the liver