Respiration

Question 1

What is aerobic respiration

Answer 1

Aerobic respiration uses oxygen to break down glucose and release energy. Some
energy is released as heat, but most is trapped in a usable form of ATP.

Question 2

What is anaerobic respiration

Answer 2

In anaerobic respiration glucose is not completely broken down and so less ATP and therefore energy is released. It also produces toxic waste products, which must either be excreted or broken down (otherwise they will build up and so kill cells).

Question 3

Name the equation for aerobic respiration

Answer 3

glucose + oxygen = carbon dioxide + water, c6h12o6 + 6O2 = 6co2 + 6h2o

Question 4

List examples of the uses of energy

Answer 4

Cell division, contraction of muscle cells, building large molecules e.g. protein, transporting molecules, maintaining body temperature

Question 5

Name the equation for anaerobic respiration in animals

Answer 5

glucose -> lactic acid

Question 6

Name the equation for anaerobic respiration in fungi and plants

Answer 6

glucose -> ethanol + carbon dioxide

Question 7

How does the human body cope with lactic acid build up

Answer 7

We keep breathing heavily after exercise to supply the extra oxygen needed to dispose of the lactic acid in our bodies. The volume of oxygen needed to oxidise the lactic acid is called the oxygen debt.

Question 8

What can lactic acid cause

Answer 8

Lactic acid builds up, causing cramps, and diffuses from muscles into the blood. In high concentrations lactic acid is toxic, so it is transported to the liver where it is oxidised.

Question 9

How can we investigate respiration using peas?

Answer 9

As the peas start to grow they respire,
releasing heat. The thermos flask is
insulated, so heat is not transferred to
the surroundings and we can measure
the change in temperature.  We only see a temperature rise in thermos A, as the peas in thermos B are dead. Soaked in Milton solution to kill off bacteria

Question 10

How can we measure respiration using insects

Answer 10

Hydrogen carbonate indicator and insects:
This indicator is red but turns yellow when
carbon dioxide concentration increases.
Carbon dioxide reacts with water to form a
weak acid.

Question 11

How can we investigate anaerobic respiration in yeast

Answer 11

This equipment can be used to investigate the effect of changing a single variable on the rate of anaerobic respiration in yeast.
Your dependent variable could be the time taken for the limewater to become cloudy. Alternatively, you could connect the delivery tube to a gas syringe, to measure the volume of carbon dioxide produced.

Question 12

List the CORMs words

Answer 12

Change, Organism, Repeats, Measure, Same

Question 13

What is cell respiration

Answer 13

Cell respiration is the process of breaking down food molecules to release ATP. It is a series of chemical reactions.

Question 14

What is an advantage of anaerobic respiration

Answer 14

The advantage of anaerobic respiration is that it allows cells to obtain a small amount of usable energy even when oxygen supply is limited