Excretion (Edexcel IGCSE Biology)

Exam Questions

2 hours10 questions
1a
Sme Calculator
6 marks

All living things carry out eight 'life processes', one of which is excretion.

(i)

Define the term excretion

(1)

(ii)

List five other life processes.

(5)

1b
Sme Calculator
1 mark

A substance that is excreted by plants is oxygen. 

State the source of this excreted oxygen.

1c
Sme Calculator
3 marks

Complete the table below using either a or a ✗ to indicate whether or not the plant processes described are examples of excretion

Process Excretion or
Water is drawn up from the roots of the plant and is lost through the leaves  
Carbon dioxide is released from respiring cells  
Dead leaves fall off deciduous plants during the autumn  

Did this page help you?

2a
Sme Calculator
2 marks

The diagram shows some human excretory organs. 

human-3

Name organ X and organ shown in the diagram.

2b
Sme Calculator
2 marks

One waste product that is excreted from the human body is urea. 

Urea is made from excess proteins that can't be stored in the body. 

Excess carbohydrates and lipids do not need to be excreted,

Suggest why excess carbohydrates and lipids do not need to be excreted.

2c
Sme Calculator
2 marks

Carbon dioxide is one of the substances that is excreted by the body.

Explain the importance of excreting carbon dioxide.

2d
Sme Calculator
2 marks

Another organ of excretion is the skin. 

Explain how the skin is able to carry out excretion. 

Did this page help you?

3a
Sme Calculator
2 marks

Separate: Biology Only

The diagram shows some glands of the endocrine system. 


q8B9tmM5_glands

(i)

Give the letter on the diagram that shows the gland that released the hormone ADH.

(1)

  A W
  B X
  C Y
  D Z

(ii)

State the name of the gland identified in part (i) that released ADH. 

(1)

3b
Sme Calculator
1 mark

Separate: Biology Only

ADH helps with a process called osmoregulation which involves regulating the quantity of water in the blood. 

ADH travels in the blood to the nephron in the kidney. 

Name the part of the nephron that is affected by ADH. 

3c
Sme Calculator
3 marks

Separate: Biology Only

Complete the sentences.

Choose answers from the box.

less ADH          less          glucose         urine          more         more ADH

The concentration of ............... is controlled by a hormone called anti-diuretic hormone.

If the blood water content is too high, ............... is released, so ............... water is reabsorbed in the kidney.

If the blood water content is too low, ............... is released, so ...............water is reabsorbed in the kidney.

3d
Sme Calculator
3 marks

Separate: Biology Only

Osmoregulation is an essential part of homeostasis. 

(i)
Define the term homeostasis

(1)

(ii)

Explain the consequences of having too much water in the blood. 

(2)

Did this page help you?

4a
Sme Calculator
3 marks

Separate: Biology Only

The diagram shows the structure of a nephron in the kidneys.

xEHxvlx__image-2

(i)

Identify structure 1 in the diagram. 

(1)

(ii)

Describe the process taking place at structure 1.

(2)

4b
Sme Calculator
2 marks

Separate: Biology Only

The fluid moving along structure 2 of the nephron in the diagram in part (a) is known as filtrate and it contains several substances.

State two substances that will form part of the filtrate in structure 2.

4c
Sme Calculator
1 mark

Separate: Biology Only

Water is reabsorbed from the filtrate back into the blood at various points along the nephron, such as structure 3 in the diagram in part (a).

Identify structure 3 in the diagram.

4d
Sme Calculator
3 marks

Separate: Biology Only

Structure 5 represents the collecting duct, which can adjust the amount of water reabsorbed into the blood depending on the needs of the body.

Complete the following sentences about the role of the collecting duct.

On a hot, sunny day the body will ............... more water due to sweating.

In order to conserve water the collecting duct will reabsorb ............... water into the blood.

This results in the excretion of ............... urine that is more concentrated.

Did this page help you?

1a
Sme Calculator
3 marks

Separate: Biology Only

The diagram shows a nephron from a kidney with three different areas, X, Y and Z.

screenshot-2022-10-24-15-42-18

The table gives the concentration of glucose and urea at X, Y and Z.

Area of nephron Concentration of glucose in mg per 100 cm3 Concentration of urea in mg per 100 cm3
X 90 32
Y 0 440
Z 0 1700

Explain the difference in concentration of glucose between X and Y.

1b
Sme Calculator
4 marks

Separate: Biology Only

(i)

Calculate how many times more concentrated the urea is in area Z compared to area Y.

Give your answer to two significant figures.

(2)

(ii)

Explain the difference in urea concentration in the filtrate found in Y and Z.

(2)

1c
Sme Calculator
4 marks

Separate: Biology Only

High blood pressure during pregnancy can result in the production of urine that contains protein.

(i)
Describe how a sample of urine could be tested to see if it contains protein.

(2)

(ii)

Protein is not normally found in urine.

Suggest why high blood pressure could cause protein to be present in urine.

(2)

Did this page help you?

2a
Sme Calculator
1 mark

Separate: Biology Only

The urinary system is used in excretion.

The diagram shows the urinary system with parts labelled A, B, C and D.

jan2021p2bq2a

(i)

 Which part of the urinary system contains nephrons?

  A  
  B  
  C  
  D  

2b
Sme Calculator
1 mark

The urinary system produces urine.

Name a substance found in urine.

2c
Sme Calculator
7 marks

Separate: Biology Only

A scientist uses this method to investigate the effect of drinking different liquids on urine production.

  • Drink 600 cm3 of water in the morning
  • Measure the volume of urine produced during the next two hours
  • Drink 600 cm3 of 0.8 % salt (NaCl) solution at the same time the following morning
  • Measure the volume of urine produced during the next two hours

The table shows the scientist’s results.

Liquid Volume of urine produced during two hours in cm3
 Water 560
Salt solution 254

(i)

Explain the scientist’s results.

(5)

(ii)

Give two other factors that affect the volume of urine produced.

(2)

Did this page help you?

3a
Sme Calculator
1 mark

Separate: Biology Only

The kidney contains nephrons involved in osmoregulation and excretion.

The diagram shows a nephron.edexcel-igcse-2b-nov-21-q3a

Which part is the Bowman’s capsule?

  A  
  B  
  C  
  D  

3b
Sme Calculator
6 marks

Separate: Biology Only

The table gives the mass of three substances transported in part A and in part D for all kidney nephrons during one day.

Substance Mass of substance in g
Part A Part D
Glucose 180 0
Water 180 000 1500
Urea 53 25

(i)
Explain the change in the mass of glucose from part A to part D.

(3)

(ii)

Calculate the percentage reabsorption of water by kidney nephrons.

(2)

(iii)

A substance containing nitrogen is broken down in the liver to produce urea.

Which substance is broken down to produce urea?

(1)

  A Fat
  B Glucose
  C Protein
  D Water

3c
Sme Calculator
4 marks

Separate: Biology Only

A drug called MDMA increases the secretion of ADH.

Explain how this increase affects urine production.

Did this page help you?

1a
Sme Calculator
3 marks

Separate: Biology Only

The diagram shows a nephron from a human kidney.

screenshot-2022-10-26-11-41-22

(i)

From which structure does ultrafiltration take place? 

(1)

  A P
  B Q
  C R
  D S

(ii)

From which structure is glucose reabsorbed? 

(1)

  A Q
  B R
  C S
  D U

(iii)

Which structure is the loop of Henle? 

(1)

  A P
  B R
  C S
  D U

1b
Sme Calculator
10 marks

Separate: Biology Only

The table gives the mean values of mass filtered per day and excreted per day for different plasma components that are filtered and reabsorbed in the nephron.

Plasma component Mass filtered per day in g Mass excreted per day in g Percentage reabsorbed
Water 180 000 1800 99.0
Sodium 630 3.0 99.5
Glucose 180 0 100.0
Urea 54   44.0

(i)

State what is meant by plasma components.

(1)

(ii)

Calculate the mean mass of urea excreted per day.

Give your answer in g. 

(2)

(iii)

Explain why glucose is reabsorbed in the nephron.

(2)

(iv)

The concentration of urine is determined by the volume of water present and the mass of dissolved substances.

A person eats a meal with a high protein and salt content and drinks a small volume of water.

Comment on how this may change the values in the table and the effect it will have on urine production.

(5)

Did this page help you?

2a
Sme Calculator
2 marks

Separate: Biology Only

The diagram shows a nephron of a kidney, with some of the structures labelled.

23e5DFwJ_p2bq6a

(i)

 From which structure are substances forced out of the blood by ultrafiltration?

(1)

  A  
  B  
  C  
  D  

(ii)

 From which structure is glucose reabsorbed into the blood by selective reabsorption?

(1)

  A  
  B  
  C  
  D  

2b
Sme Calculator
2 marks

Separate: Biology Only

In homeostasis, the kidney is involved in the control of blood concentration.

(i)

State the name for the control of blood concentration.

(1)

(ii)

Another function carried out by the kidney is excretion.

State what is meant by the term excretion.

(1)

2c
Sme Calculator
4 marks

Separate: Biology Only

Diabetes insipidus is a medical condition in which the body is unable to produce ADH.

Explain how diabetes insipidus affects the control of blood concentration.

2d
Sme Calculator
3 marks

Separate: Biology Only

Desmopressin is a drug used to reduce the symptoms of diabetes insipidus.

(i)

Suggest what effect the drug would have on the nephron.

(1)

(ii)

Describe the effects the drug would have on urine production.

(2)

Did this page help you?

3a
Sme Calculator
2 marks

Separate: Biology Only

The human kidney is an organ that is able to process excretory products from human metabolism.

Concentration of urine is calculated using this formula.

concentration space in space milliosmoles space per space dm to the power of 3 space end exponent equals space fraction numerator amount space of space waste space in space milliosmoles over denominator volume space in space dm cubed end fraction

The amount of waste the kidneys produce per day is 600 milliosmoles.

The maximum concentration that the human kidneys can produce is 1400 milliosmoles per dm3.

Calculate the minimum volume of urine that must be produced each day.

Give your answer in cm3.

3b
Sme Calculator
1 mark

Name another organ that carries out excretion in the human body.

3c
Sme Calculator
5 marks

Separate: Biology Only

Explain the role of the nephron in osmoregulation.

Did this page help you?