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grade 8 qp Science

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1. What does the xylem transport in a plant?
A. Water and dissolved sugars B. Water and dissolved mineral salts C. Water only D. None
2. How are sucrose and amino acids transported in a plant?
A. Through the phloem B. Through the xylem C. Through the xylem and phloem D. through the roots.
3. Which type of blood vessel carries blood away from the heart?
A. Artery B. Vein C. Capillary D. All
4. From which chamber of the heart does blood leave to go to the lungs?
A. left Atrium
B. Right atrium
C. Left ventricle
D. Right ventricle
5. Which of these is a common risk factor for heart disease?
A. Having low blood pressure
B.Being overweight
C.Exercising regularly
D. None
6. What is the purpose of blood clotting after a skin wound?
A. To stop the loss of blood and trap microorganisms in the capillaries
B.To stop the loss of blood and prevent the entry of microorganisms into the body
C. To use up excess platelets in the blood
7. How is carbon dioxide transported in the blood?
A.In the plasma
B.In the red blood cells
C.In the white blood cells
8. A component which Ingest pathogens and producing antibodies
A. Plasma B. Red Blood cells C. White blood cells D. Platelets.
9. the shape of the red blood cells to maximise their surface area for oxygen absorption
A. circular
B. biconvex
C. cylindrical
D. biconcave shape
10. Water passes from the soil water to the root hair cell’s cytoplasm by.
A. osmosis
B. Diffusion
C. pressure
D. All
11. the major function of this nutrient is growth and repair.
A. Carbohydrates
B. Fats
C. Proteins
D. vitamins
12. What molecules are the buillding blocks of proteins?
A. Amino acids
B. Fatty acids
C.Sugars
D. glucose
13. The digestion of which food molecule by enzymes begins in the mouth?
A. Glucose
B.Protein
C.Starch
D. Aminoacids
14. What is the main function of the small intestine?
A. Absorption of digested food molecules
B. The breakdown of starch into maltose
C.The absorption of water from the gut
D. secretes hydrochloric acid
15. Which is the major region of the gut where lipids are broken down
A. Mouth
B. Stomach
C. Small intestine
D. Oesophagus
16. What is the function of bile?
A. Bile contains a mixture of digestive enzymes
B. Bile emulsifies lipids
C. Bile contains hydrochloric acid to provide the optimum pH for pepsin activity
D. Bile rolls food into small balls.
17. An exit opening of gut through which faeces leaves the body.
A.Large intestine
B.Colon
C.Rectum
D.anus
18. This organ produces protease, lipase and maltase.
A.Small Intestine
B.Pancreas
C.Mouth
D.Liver
19. the digestive enzyme which acts on starch is
A. amylase
B.maltase
C.protease
D.lipase
20. this transports blood from capillaries to the heart
A.arteries
B. heart
C. Veins
D.xylem
Section B
1. The diagram shows the human circulatory system.
Parts of the system are labelled with the letters A to G.
Use the diagram to identify parts of the circulatory system from their descriptions.
Write your answers in the table.
[4]
description
letter
the part that pumps blood to the lungs
the part where oxygen leaves the blood
the part where the blood is at its greatest
pressure
an artery that takes blood to the body
2. In an osmosis experiment, after 45 minutes, a potato cylinder had lost 2.4 g in mass.
Calculate the rate of water loss from the potato cylinder in grams per hour. [2 marks]
3. Explain why a plant will wilt if not watered. [2 marks]
4. Describe and explain how blood in the right ventricle travels to the left atrium. [3 marks]
5. A student used red blood cells to carry out an investigation into cell membranes. Red blood
cells were placed in salt solutions at three different concentrations. A sample of red blood cells
was then removed from each concentration and placed on a microscope slide. The cells were
viewed using a microscope for a period of time.
Concentration of salt solution (%)
0.0
0.9
3.0
Observation of red blood cells
swell and burst
remain the same size
smaller and shriveled
Explain the observations shown in the table. [3 marks]
6. Pierre plays a sport called rugby.
To keep fit he eats a special diet and exercises often.
(a) To improve his strength, Pierre eats lots of chicken.
Name the main nutrient present in chicken.
[1]
(b) Explain how this nutrient improves Pierre’s strength.
[1]
7. This diagram shows the digestive system in the human body.
(a) Name parts A to F (not X or Y). [6]
(b) X is a gland below the mouth.
What substance does X secrete? [1]
______________________________
(c) D contains a strong acid. What is
the purpose of this acid?[1]
________________________________
(e) What process takes place in B? [1]
________________________________
8. A food contains protein. Describe what happens to this protein after the food reaches the
stomach.
_________________________________________________________________________
_________________________________________________________________________
_________________________________________________________________________
b. Name the enzyme that catalyses the digestion of dietary fats.
_________________________________________________________________________
c. What are the products of fat digestion?
d. Name the substance produced by the liver that helps in the digestion of dietary fats.
_________________________________________________________________________
e. Explain how this substance helps in the digestion of dietary fats.
9. Q10.This table shows the percentage of starch converted into maltose by a synthetic enzyme,
amylase Q, under different conditions.
a) What are the optimum conditions for Amylase Q? [2]
________________________________________________________________________
b) What is the effect of an increase in temperature on enzyme activity? [1]
________________________________________________________________________
________________________________________________________________________
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