Grade 8 Natural Science Topic Tests & Memos Term 1

Photosynthesis and Respiration Test 1:

 

Question 1:

1.1        What is the function of chlorophyll?                                                                                         (3)

1.2        What gas is bound in the process of photosynthesis?                                                              (1)

1.3        1What gas is released during the process of photosynthesis?                                                    (1)

1.4        Through which structure in the leaf does gas exchange take place?                                        (1)

1.5        Where does the energy that makes photosynthesis possible, come from?                                (1)

 

Question 2:

 

2.1        What is the product of respiration?                                                                                           (3)

2.2        Name three places where respiration can take place.                                                              (3)

 

Question 3:

 

3.1        When does respiration take place in plants?                                                                           (1)

3.2        When does photosynthesis take place in plants?                                                                   (1)

 

Question 4:

 

4.1        What is the name of the sugar produced by plants?                                                                 (1)

4.2        In what form is food stored in the plant?                                                                                 (1)

 

Question 5:

 

5.1        Name two types of respiration?                                                                                                 (2)

5.2        How do we test for carbon dioxide?                                                                                          (4)

5.3        Give an energy transfer diagram for the origin of energy to where you use energy to walk.

Photosynthesis and Respiration Test 2:

 

Question 1:

 

1.1        Give the chemical formula for the process of photosynthesis                                            (6)

1.2        Give the chemical formula for the process of respiration.                                                   (6)

Question 2:

 

2.1        Define the following terms:

2.2        Photosynthesis.                                                                                                                               (4)

2.3        Respiration.                                                                                                                                     (4)

 

Question 3:

 

3.1        What colour will the starch in a leaf turn to if it is placed in iodine?                                            (1)

3.2        What solution is used to test for CO2?                                                                                         (2)

3.3        How do we test for the presence of O2 which is a product of photosynthesis?                             (2)

Photosynthesis and Respiration Test 3:

 

Question 1:

 

1.1        What is the source of energy used in respiration?                                                                 (1)

1.2        What type of energy does the starch formed in the leaf store?                                         (1)

1.3        Why can't animals photosynthesize and produce their own food?                                   (1)

1.4        Where does cellular respiration take place?                                                                           (1)

1.5        What are the waste products formed during respiration?                                                  (2)

 

Question 2:

 

2.1        What happens to the by-products of photosynthesis?                                                         (4)

2.2        Describe the process of respiration.                                                                                          (6)

2.3        Why is it advisable to remove plants from a pneumonia patient in the evening?         (3)

 

Question 3:

 

3.1        Why are the following processes important:

3.2        Respiration                                                                                                                                      (2)

3.3        Photosynthesis                                                                                                                                (2)

 

Question 4:

 

List two differences between respiration and photosynthesis in tabular form.                         (4)

Microorganisms:

 

1.           Describe the difference between Viruses and Bacteria.                                         (4)

2.           Name three useful organisms and describe their role in industry.                       (6)

3.           Name 3 properties of Algae and Fungi (yeasts).                                                       (6)

4.           Protozoa can be harmful. Describe what makes these organisms harmful and give an example.                                                                                                                                                (2)

5.           Karel likes to bake. What organisms are involved in the process of making food?    (2)

6.            Fermentation is a process that produces butter. Is this sentence true or false? If your answer is false, motivate why.                                                                                              (2)

Photosynthesis and Respiration Memorandum 1:

 

Question 1:

 

 

1.1        Chlorophyll helps the leaf produce food through photosynthesis.

1.2        Carbon dioxide.

1.3        Oxygen.

1.4        Skin mouth.

1.5        Sunlight

 

Question 2:

 

2.1        Carbon dioxide, water and energy.

2.2        In Lungs, in leaves, in cells in the body.

 

Question 3:

 

3.1        Through the night.

3.2        Throughout the day when the sun shines.

 

Question 4:

 

4.1        4.1 Glucose.

4.2        Starch.

 

Question 5:

 

5.1        Aerobic and anaerobic.

5.2        Dissolve lime in water.

5.3        Bubble the gas through the lime water.

5.4        If the lime water becomes milky, there is carbon dioxide in the gas.

5.5        Sunlight             Photosynthesis             Glucose           Starch            Intake          Respiration        Energy

 

Photosynthesis and Respiration Memorandum 2:

Question 1:

Question 2:

 

2.1        Photosynthesis is the process where a green plant, with chlorophyll, uses carbon dioxide and water to produce sugar and give off oxygen as a by-product.                                    (4)

2.2        Respiration is the process where sugar is broken down in the presence of oxygen to produce energy with water and carbon dioxide as by-products.                                                      (4)

 

Question 3:

 

3.1        Dark purple blue.                                                                                                                            (1)

3.2        Clear lime water.                                                                                                                             (2)

3.3        A burning splinter of wood will ignite in the presence of oxygen.                                               (2)

Photosynthesis and Respiration Memorandum 3:

Question 1:

 

1.1        Sunlight                                                                                                                                         (1)

1.2        Potential chemical energy                                                                                                            (1)

1.3        Animals do not have chlorophyll in their bodies for photosynthesis.                                          (1)

1.4        In the mitochondrion.                                                                                                                   (1)

1.5        Water and carbon dioxide.                                                                                                           (2)

Question 2:

 

2.1        Water and oxygen are given off through the leaves. Water can also be used to transport substances in the plant. Oxygen can also be used for the small amount of photosynthesis that takes place during the day for energy for growth and other processes in the plant.      (4)

2.2        Respiration takes place in every cell of the organism.

Respiration requires oxygen to break down food such as glucose and starch to provide energy.

The type of respiration is called aerobic energy.

Carbon dioxide and water are by-products of respiration.                                                  (6)

2.3        Pneumonia patients do not absorb enough oxygen, and therefore need more oxygen than a healthy person. Why is it advisable to remove plants from a pneumonia patient, in the evening. During the night, respiration takes place in plants. Oxygen is used in the process and carbon dioxide is given off. The much-needed oxygen for the patient is used up by the plant.(3)

 

 Question 3:

 3.1   Respiration provides the much-needed energy that makes life possible.                                         (2)

3.2   Provides the much-needed oxygen which is also a condition of life. It is necessary to provide energy through respiration.                                                                                                               (2)

 Question 4:

Respiration	Photosynthesis
Does not require chlorophyll to occur.	Needs chlorophyll to occur.
Needs oxygen to occur.	Sulphur is a product of photosynthesis.

                                                                                                                                                          (4)

Memorandum:

1.               Bacteria are unicellular and can function together or independently of a host. Viruses can only function inside the cells of their host.

 2.

a.       Decomposers: break down organic matter in nature.

b.       Water purification: Organisms feed on sludge in water.

c.        Digestion: Bacteria in the human colon protect us from harmful organisms that can possibly be found in food. These bacteria feed on the food inside the stomach and contribute to the process of excretion.

3.       Algae: Food manufacturers, plant organisms, large cell size of the microorganisms.

          Fungi: Can not produce their own food. Life on sugars. Some emit alcohol and carbon dioxide.

4.       They cause disease that can sometimes be fatal like malaria.

5.       Yeast cells are used to stir in bread dough before baking bread.

6.       No, yogurt is where fernmetation is involved.