1
1 mark
1 markWhat is urea produced from?
Fatty acids
Glucose
Amino acids
Glycerol
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13.1 Excretion in Humans
21 mark
1 markWhich of the following is a correct example of excretion in mammals?
The production of carbon dioxide from aerobic respiration.
The removal of excess salts from the blood.
The removal of undigested food from the anus.
The release of hormones from glands.
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31 mark
1 markWhich of the following is not a main function of the kidneys in a healthy person?
To reabsorb all glucose.
To regulate blood pressure.
To breakdown toxins.
To eliminate excess sodium and potassium ions.
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41 mark
1 markThe image below shows the structure of the human urinary system.
Which row of the table below correctly matches the structures in the image to their names?
| renal artery | urethra | ureter | |
| A | W | Z | X |
| B | W | Z | Y |
| C | X | Y | Z |
| D | X | W | Y |
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51 mark
1 markExtended only
Which of the following would not be a function of the liver?
Assimilation of amino acids
Breakdown of alcohol
Deamination
Excretion of urea
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11 mark
1 markWhich row of the table below correctly displays the correct roles of the following organs in processing waste in the human body?
| kidneys | liver | lungs | |
| A | excretes urea | excretes amino acids | removes carbon dioxide |
| B | removes carbon dioxide | deamination of amino acids | excretes urea |
| C | removes urea from blood | deamination of amino acids | removes carbon dioxide |
| D | excretes urine | deamination of urea | removes carbon dioxide |
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21 mark
1 markThe following table shows the composition of blood entering the kidneys of a healthy person.
| substance | % composition of blood entering the kidney |
| glucose | 0.20 |
| urea | 0.01 |
| protein | 7.00 |
Which row of the table below would show the percentage composition of blood of the same substances in the urine of a healthy person?
| composition of urine / % | |||
| glucose | urea | protein | |
| A | 0.00 | 2.50 | 0.00 |
| B | 0.00 | 2.50 | 3.50 |
| C | 2.00 | 0.00 | 7.00 |
| D | 0.20 | 0.01 | 0.00 |
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31 mark
1 markWhich of the following factors would affect the volume and concentration of urine produced by the kidneys?
- Exercise
- Temperature
- Water intake
1 and 3 only
2 and 3 only
3 only
All 3 of the above
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41 mark
1 markThe table below shows the composition of a solution found in the human body.
| component | concentration / arbitrary units |
| glucose | 0.00 |
| urea | 4.00 |
| protein | 0.00 |
| salts | 3.00 |
| amino acids | 0.00 |
In a healthy person, which of the following structures would contain this solution?
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51 mark
1 markExtended only
The image below shows a number of organs involved in helping rid the body of waste products.
Excess amino acids from the diet cannot be stored by the body. One of the products of their breakdown is urea.
Which row of the table below is correct?
| name for breakdown of excess amino acids | makes urea | removes urea from the blood | |
| A | assimilation | Y | Z |
| B | deamination | X | Y |
| C | assimilation | Y | X |
| D | deamination | X | Z |
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11 mark
1 markTo remain healthy, a person must be able to excrete a number of waste products produced as a result of metabolism.
A list of excretory products is given below.
Which of the following would be lost from both the kidneys and lungs?
Water
Carbon dioxide
Glucose
Urea
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21 mark
1 markExtended only
Each kidney contains one million kidney tubules called nephrons. A nephron is shown in the image below.
Which row of the table below correctly shows where filtration and selective reabsorption occur?
| filtration | selective reabsorption | |
| A | 1 | 2 |
| B | 2 | 4 |
| C | 2 | 3 |
| D | 1 | 3 |
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31 mark
1 markExtended only
Which of the following substances would be reabsorbed by the kidneys?
Salts, urea and glycogen
Salts and glycogen
Salts and glucose
Urea and glucose
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41 mark
1 markExtended only
Which of the following statements correctly describes the function of the kidneys?
Reabsorbing glucose and removing urea.
Removing glucose and reabsorbing salts.
Deamination and reabsorption of glucose.
Making and removing urea.
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51 mark
1 markWhich of the following organs are responsible for removing excretory products from the blood?
Bladder and kidneys
Kidneys and lungs
Lungs and liver
Bladder and liver
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