Name______________________ Class___________

I am confident that I understand this and I can apply this to problems ? I have some understanding but I need to revise this some more I don’t understand this and I need help with it

1.7 Respiration Covered()

How well can you do this?

1. The term “respiration” refers to the chemical process by which energy is released from glucose. ?

2. Every living cell in every living organism requires the conversion of glucose to energy by respiration. ?

3. There are two types of respiration:a) Aerobic – with oxygenb) Anaerobic – without oxygen

?

4. Aerobic respiration means “with oxygen” and releases a greater amount of energy than anaerobic respiration. ?

5. Glucose and oxygen are required for aerobic respiration to take place. ?

6. Water and carbon dioxide are waste products of respiration. ?

7. I can describe an experiment which shows how energy can be released from food and oxygen (burning food experiment). ?

8. I can describe an experiment which shows how respiration occurs in the cells of all living things (germinating peas vs. boiled peas experiment).

?

Covered()

How well can you do this?

9. Energy, water and carbon dioxide are the products of aerobic respiration. ?

10. I can write a word equation for respiration, identifying the raw materials & products. ?

11. Anaerobic respiration means “without oxygen” and releases less energy than aerobic respiration. ?

12. Glucose is required for anaerobic respiration to take place. ?

13. Lactic acid is a product of anaerobic respiration when it occurs in animals and bacteria. ?

14. Alcohol is a waste product of anaerobic respiration in plants and fungi. ?

15. Carbon dioxide is released during anaerobic respiration in plants. ?

16. I can write a word equation for aerobic and anaerobic respiration identifying the raw materials & products. ?

17. I can give examples of how aerobic & anaerobic respirations are used in industry. ?

Name______________________ Class___________

I am confident that I understand this and I can apply this to problems ? I have some understanding but I need to revise this some more I don’t understand this and I need help with it

N5 Outcomes Covered()

How well can you do this?

1. Respiration is a biological process in which energy stored in food (glucose) is released for use in cells. ?

2. Respiration is a series of enzyme controlled steps. ?

3. Respiration stores chemical energy from food in a high energy molecule called adenosine tri-phosphate (ATP). ?

4. Adenosine di-phosphate (ADP) chemically joins with an inorganic phosphate (Pi) to generate (ATP).

ADP + Pi ATP ?

5. Breaking the bond between (ADP) and the terminal inorganic phosphate releases energy for cellular reactions. (Nerve impulses, muscle contraction, cell division & protein synthesis). ?

6. ATP is broken down to ADP + Pi and regenerated to ATP in a cyclic reaction. ?

7. Respiration begins with glycolysis, which takes place in the cytoplasm of a ?

cell.

8. Glycolysis requires energy from 2 ATP molecules and produces 4 ATP molecules giving a net gain of 2 ATP molecules.

?

9. During glycolysis each glucose molecule is broken down to 2 x pyruvate molecules. ?

10. In the presence of oxygen (aerobic respiration) pyruvate enters the kreb's cycle. ?

11. Kreb's cycle takes place in the central matrix of the mitochondria. ?

12. Hydrogen from intermediate compounds is removed in the kreb’s cycle and carried to a third stage in respiration by high energy transfer molecules. ?

13. Carbon dioxide is given off as a by product in respiration. ?

14. Oxygen combines with hydrogen to produce water during aerobic respiration. ?

15. Oxygen is carried in red blood cells bound to a special protein called ?

haemoglobin.

16. For each glucose molecule entering the kreb's cycle via pyruvate, 36 molecules of ATP are produced and when added to the 2 ATP molecules from glycolysis give a total yield of 38 ATP. ?

17. The equation for respiration is summarised asGlucose + Oxygen Carbon dioxide + Water

?

18. In the absence of oxygen (anaerobic respiration) pyruvate cannot enter the kreb's cycle and must enter a different pathway.

?

19. In animals, pyruvate is converted to lactic acid and that lactic acid causes fatigue and cramp.

Glucose Lactic Acid ?

20. When oxygen becomes available lactic acid can be converted back to pyruvate and then enter the kreb's cycle. This is repaying the oxygen debt. ?

21. Anaerobic respiration in plants results in the production of carbon dioxide and ethanol. ?

22. This reaction is called fermentation and is non-reversible. ?

Glucose Carbon dioxide + ethanol

23. Fermentation takes place in the cytoplasm of a cell. ?

24. Aerobic respiration starts in the cytoplasm of the cell and is completed in the mitochondrion. ?

Respiration Summary Notes National 4

Respiration is the chemical process where we release energy from our food (glucose).

Every cell needs to release energy from glucose and there are two types of respiration;

Aerobic – with oxygenAnaerobic – without oxygen

The equation for aerobic respiration can be summarised as follows:

Glucose + oxygen Carbon dioxide + water + ENERGY

Raw materials Products

All animals and plants make the same products when there is oxygen present.

In anaerobic respiration, glucose is still required but no oxygen.

For this reason, less energy is produced.

In Animals and Bacteria, anaerobic respiration produces not Carbon Dioxide and Water, but Lactic Acid.

Lactic acid is what makes your muscles sore when you are exercising. Once you stop exercising and your breathing catches up to deliver enough oxygen, you can return to aerobic respiration and the lactic acid is removed.

Glucose Lactic acid

(Remember – lactic acid was made by the bacteria in the milk to produce yoghurt)

In plants and fungi, anaerobic respiration produces Carbon Dioxide and Alcohol.

Glucose Carbon Dioxide + Alcohol + little energy

Raw material Products

The carbon dioxide is released and cannot be regained.

(Remember – yeast (fungus) makes Carbon Dioxide and Alcohol for making dough rise and in alcohol production)

Respiration Summary Notes National 5

Adenosine triphosphate (ATP) is a molecule made up from an adenosine molecule bound to three inorganic phosphates (Pi).

Energy which is stored in ATP is released when the bond attaching the terminal phosphate is broken by enzymes.

Once the terminal phosphate is broken off we are left with ADP + Pi (adenosine di-phosphate and inorganic phosphate).

During respiration ATP is regenerated from ADP + Pi, in an enzyme controlled process called phosphorylation.

this reaction can be summarised as:

ATP ADP + Pi High Low energy energy state State

When an energy rich substances such as glucose are broken down they produce energy which is used to produce ATP.

If glucose is burned in a dish it releases its energy quickly as heat and light. However in a living cell respiration releases energy gradually through a series of enzymes controlled steps.

There are many molecules of ATP in each living cell. As ATP is broken down to produce ADP + Pi, the energy released is used to fuel biological processes such as muscle contraction, transmission of nerve impulses, cell division and protein synthesis.

AdenosinePi Pi Pi

Terminal phosphate

Adenosine

Pi

PiPi Energy

In order to regenerate ATP, cells require glucose which is derived from digested carbohydrates. Glucose is carried, dissolved in the blood plasma, to every cell in the body where it is required. As the glucose is used up in the cells the concentration levels in the cell remain low while the concentration in the blood is higher allowing for diffusion of glucose from the blood into the cells.

Respiration can happen with or without oxygen, however it is more efficient if oxygen is available.

Aerobic respiration is the term used to describe respiration with oxygen.

Glucose + Oxygen Carbon dioxide + water

Oxygen is transported to the cells bound to a special protein called haemoglobin in red blood cells; oxygen is used by the cells maintaining a low concentration inside the cell. As we breathe, more oxygen enters the blood, maintaining a high concentration of oxygen in the blood reaching cells. This allows oxygen to move into the cells by diffusion.

Stage 1 – Glycolysis

Respiration begins in the cytoplasm of a cell and involves the breakdown of one glucose molecule into two molecules of pyruvate.

In order to do this the cell must use energy from 2 ATP molecules; at the same time producing 4 ATP molecules giving a net gain of 2 ATP molecules.

2 x Pyruvate

Glucose

Stage 2 – Kreb’s cycle (with oxygen only)

Pyruvate enters into the Kreb’s cycle a series of enzyme controlled reactions which takes place in the mitochondria of the cell. During this part of the process hydrogen is removed by high energy carrier molecules. Carbon dioxide is also given off as a by-product.

Stage 3

The hydrogen is used in the hydrogen transfer system to produce ATP before finally combining with oxygen to form water.

Including glycolysis, each molecule of glucose produces 38 ATP.

Carbon dioxide and water are breathed out as waste products.

Anaerobic respiration

There are occasions when oxygen is not available. Under these conditions anaerobic respiration takes place.

Pyruvate cannot enter the Kreb’s cycle in the absence of oxygen so only glycolysis can take place and only 2 ATP can be produced overall. The pyruvate therefore must enter an alternative pathway. This is different in animals and plants.

In animals pyruvate is converted to lactic acid which causes fatigue and cramp in muscle tissue. When oxygen becomes available lactic acid is converted back to pyruvate which can then enter the Kreb's cycle. The reaction is said to be reversible.

In plants pyruvate is broken down to carbon dioxide and ethanol (an alcohol). This is a non-reversible reaction which is also known as fermentation.

+

PyruvateLacticAcid

Pyruvate Carbon dioxide

Ethanol

Anaerobic respiration is less efficient than aerobic respiration producing 20 times less energy. Anaerobic respiration takes place in the cytoplasm and only involves energy produced in glycolysis.

1. The diagram below shows the main stages of respiration.

a) Name stage 1.__________________

pyruvate

b) Name substances X and Y.

X _____________________

Y _____________________

c)Which substance shown in the diagram is the source of the energy used to synthesise ATP?

__________________________

d) Complete the following word equation which represents the synthesis of ATP

___________ + __________ + energy ATP

e) How many molecules of ATP are produced per glucose molecule during each of the following stages?

Stage 1 ____________

Stage 2 ____________

f) During aerobic respiration some energy is lost from the cell. In which form is this energy?

____________________2. The experiment shown below was set up to demonstrate aerobic respiration in peas that are germinating (starting to grow).

After two days, the level of liquid had risen in tube Y but had not risen in tube X.

i) Explain the purpose of A as a control in this experiment.

_____________________________________________________________________

_____________________________________________________________________

ii) Predict the effect on the level of the liquid in tube Y if a greater mass of peas is used.

_____________________________________________________________________

b) The following list contains some features of aerobic and anaerobic respiration in germinating peas.

List

W Does not use oxygenX Produces carbon dioxideY Yields 38 molecules of ATP per glucose moleculeZ Produces ethanol

Complete the table below by writing the letters from the list in the correct columns.Each letter may be used more than once.

Aerobic respiration in germinating peas

Anaerobic respiration in germinating peas