BioChem 2.8 Cell respiration

Question 1

How can living organisms release energy?

Answer 1

Release of energy occurs by cell respiration

Question 2

What is cell respiration?

Answer 2

Cell respiration is the controlled released of energy from organic compounds to produce ATP

Question 3

Where do human derive their energy from?

Answer 3

Energy comes from broken down organic compounds we gain from food. Also use: - carbohydrates - lipids - proteins (sometimes)

Question 4

What do plants use for cell respiration?

Answer 4

Carbohydrates or lipids (made by photosynthesis)

Question 5

How is glucose turned into energy? What is this process called?

Answer 5

Glucose and oxygen (breakdown through burning) makes energy This is called aerobic respiration

Question 6

How can the conversion into energy be usable?

Answer 6

Cell respiration uses Enzymes to control that energy released is retained in a usable form/immidiately available form, called ATP

Question 7

How is ATP made?

Answer 7

A phosphate group has to be liked to ADP. This reaction requires energy that comes from the break down of organic compounds

Question 8

Give an example of cell respiration?

Answer 8

Energy is released in muscle fibres by breaking down glucose into CO2 and H2O The energy can then be used for muscle contraction

Question 9

Is ATP transferred from cell to cell?

Answer 9

No. All cells require a continuous supply. (this is why they are so essential)

Question 10

What is a cell’s source of energy?

Answer 10

ATP from cell respiration is IMMEDIATELY available as a source of energy.

Question 11

Why do cells require energy?

Answer 11

• Synthesizing large molecules like DNA, RNA and proteins - (Active membrane transport) pumping molecules or ions across membrane by active transport - moving things around inside of the cell, such as chromosomes, vesicles, protein fibres (for muscle contraction)

Question 12

Why do cells require a continual source of ATP?

Answer 12

ATP –> Heat Energy –> Lost to environment

Question 13

What occurs during anaerobic respiration?

Answer 13

Glucose is broken down in the cytoplasm WITHOUT using any oxygen

Question 14

Does anaerobic cell respiration produce a lot of yield?

Answer 14

Anaerobic respiration gives small yield of ATP from glucose, but ATP can be produced QUICKLY

Question 15

When is anaerobic respiration useful?

Answer 15

• When a short but rapid burst of ATP production is needed - when oxygen supplies run out in respiring cells - in environments that are deficient in oxygen (e.g. water logged soils)

Question 16

What are the products of anaerobic respiration in animals/humans?

Answer 16

Glucose -> lactic acid (usually in dissolved form called lactate)

Question 17

What are the products of anaerobic respiration in plants?

Answer 17

In yeast/plants, glucose -> ethanol and CO2

Question 18

Why is aerobic respiration more used than anaerobic?

Answer 18

Anaerobic only gives a very small yield and the products (lactate and ethanol) are TOXIC in excess and must be REMOVED from cells or be produced in LIMITED quanities

Question 19

Where does this occur? & What kind of respiration?

Answer 19

Animals/Humans for anaerobic respiration

Question 20

Where does this occur? & what kind of respiration?

Answer 20

Occurs in Yeasts and plants for anaerobic respiration

Question 21

How is bioethanol produced?

Answer 21

Produced from sugar cane/corn using yeast which converts the sugar into ethanol by anaerobic respiration

As only sugars can be converted, starch and cellulose have to be broke down using enzymes.

Ethanol from yeasts has to be purified

Question 22

When is the lactate production in humans used?

Answer 22

Lactate production in humans when anaerobic respiration is used to maximize the power of muscle contraction (running/weight lifting)

Question 23

What cell respiration requires oxygen?

Answer 23

Aerobic respirtation requires oxygen

Question 24

How much yield does aerobic respiration produce?

Answer 24

Gives a large yield of ATP as glucose can be fully broken down

Question 25

What are the byproducts of aerobic respiration?

Answer 25

CO₂ and Water

Question 26

Where does aerobic respiration occur?

Answer 26

Insude of the mitochondrion

Question 27

What process is this?

Answer 27

Aerobic respiration