U2 Respiration

Question 1

What is ATP? +uses

Answer 1

A high-energy compound capable of releasing energy for:
-muscle contraction
-synthesis reactions
-active transport
-etc.

Question 2

What is ATP made up of? and what is it broken down into?

Answer 2

One adenosine
3 inorganic phosphate groups

Broken down into ADP + Pi (energy released)

Question 3

What is phosphorylation?

Answer 3

the addition of a phosphate group

Question 4

What does ATP act as a link between?

Answer 4

energy-releasing reactions and energy consuming reactions

Question 5

Glucolysis-4 facts

Answer 5

It is the first stage of aerobic respiration

It occurs in the cytoplasm

Does not require oxygen

Glucose (6 carbon sugar) is broken down into two molecules of pyruvate (3 carbon molecule) in a series of enzyme controlled reactions

Question 6

What is ATP required for in glycolysis?

Describe the energy investment phase and the energy pay-off phase.

Answer 6

The phosphorylation of glucose and intermediates during the series of reactions

This requires an investment of 2 ATP molecules in the ENERGY INVESTMENT PHASE

but results in the generation of 4 ATP molecules in the ENRRGY PAY-OFF PHASE

NET GAIN of 2 ATP molecules

Question 7

What holds the carbons in a 6 carbon glucose molecule together?

Answer 7

hydrogen bonds

Question 8

glycolysis-What happens when the 6C glucose molecule is split?

Answer 8

hydrogen ions and electrons are released and must bind to a carrier

The carrier in glycolysis is NAD which becomes NADH when carrying hydrogen molecules

1-the enzyme dehydrogenase removes the hydrogen ions and electrons from the glucose
2-they are temporarily bound to a coenzyme (NAD) which acts as a hydrogen acceptor and carrier
3-NAD carries the hydrogen ions and electrons to the Electron Transport Chain to be used later

Question 9

Where is the Electron transport chain?

Answer 9

Inner membrane of the mitochondria

Question 10

Where does the citric acid cycle take place?

Answer 10

matrix of the mitochondria

Question 11

What happens after glycolysis?

Answer 11

If oxygen is present pyruvate diffuses into the matrix
where it loses a carbon atom to become acetyl

The carbon is released as CO2 and is released from the cell

Question 12

What does the acetyl group join with?

Answer 12

a molecule called co-enzyme A forming acetyl co-enzyme A. The co-enzyme transports the acetyl group to the citric acid cycle

Question 13

After acetyl has been transported to the citric acid cycle, what does it combine with? +what is it followed by?

Answer 13

oxaloacetate to form citrate.

This is followed by several enzyme controlled steps.

This cycle will eventually lead to the regeneration of oxaloacetate.

Question 14

How many ATP molecules are generated in the citric acid cycle

Answer 14

1 molecule per pyruvate

Question 15

What is released throughout the citric acid cycle?

Answer 15

Carbon dioxide

Question 16

What is the Electron Transport Train?

Answer 16

The final stage of the respiration pathway.

This is where most ATP is produced.

It is a collection of proteins on the inner membrane (crustal) of the mitochondria

A series of carrier proteins attached to the inner mitochondrial membrane.

Question 17

What is the inner membrane (crustal) of the mitochondria made up of?

Answer 17

proteins and phospholipids like any membrane

Question 18

Where are the electrons from in the electron transport chain?

Answer 18

The NADH from glycolysis and citric acid cycle release the electrons and pass them to the electron transport chain

Question 19

Stages of the electron transport chain

Answer 19

1-Electrons are passed along the chain, releasing energy

2-This energy is used to pump H+ across the inner mitochondrial membrane, creating a higher concentration outside of the matrix

3-H+ then flows back in across the membrane via molecules of ATP synthase. This enzyme converts ADP+Pi into ATP

Question 20

How is the majority of the ATP produced during cellular respiration generated?

Answer 20

Electron Transport Chain

Question 21

ETC-What is the final electron acceptor?

Answer 21

Oxygen is the final electron acceptor and combines with the electrons and hydrogen ions that reach the end of the chain to make water.

Question 22

3 features of fermentation

Answer 22

occurs when oxygen is absent

only glycolysis can occur

the process of fermentation is different in plants and animals

Question 23

Fermentation in plants and yeast

Answer 23

glucose->2pyruvate->ethanol + CO2

first stage=net gain of 2ATP

Irreversible

Question 24

Fermentation in animals

Answer 24

glucose->2pyruvate->lactation

first stage=net gain of 2ATP

oxygen debt build up converts pyruvate into lactate.
When oxygen debt is repaid, lactate is converted back into pyruvate (reversible)

Question 25

How many ATP are produced per molecule of glucose during aerobic respiration?

Answer 25

38ATP

Question 26

How many ATP are produced from 1 molecule of glucose during fermentation?

Answer 26

2ATP
(only produced during glycolysis->netbgain)

Question 27

What is metabolic rate?

Answer 27

The quantity of energy consumed per unit of time

Question 28

How can metabolic rate be measured?

Answer 28

energy production (heat) per unit of time

oxygen consumption per unit of time

CO2 production per unit of time

Question 29

What is a calorimeter used for?

Answer 29

To measure metabolic rate. Energy production (heat) per unit of time is recorded

Question 30

What is a respirometer used for?

Answer 30

To measure metabolic rate.

Probes can be used to detect changes in CO2 and O2 concentration