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Lungs have numerous alveoli to increase surface area for diffusion of gases; alveoli have thin
membrane which minimizes resistance against gases; blood flowing in the capillaries contains
less oxygen and more C02 since it is from the body tissue; alveoli are supplied with air through bronchioles which link them to the trachea; alveoli are supplied with many capillaries containing
blood to transport gases; air in the alveoli contain more oxygen and combine with haemoglobin,
forming oxyhaemoglobin; C02 diffuses out of the blood into the alveoli ;from where it is exhaled;
sharon kalunda answered the question on May 22, 2019 at 10:53
- An experiment was set up to demonstrate the necessity of carbon (IV) oxide for
photosynthesis in a certain green plant as shown below. The plant was...(Solved)
An experiment was set up to demonstrate the necessity of carbon (IV) oxide for
photosynthesis in a certain green plant as shown below. The plant was first kept
darkness for 48 hours before the experiment.
a), Why was the plant kept in darkness for 48 hours before the start of this experiment.
b), What was the role of sodium hydroxide?
ci)What was the results shown by the leaf in the flask when it was tested for presence of starch after
the set up was exposed to light for a day?.
ii), Give reasons for your answer in (c) I above
d. Suggest a control for this experiment.
e), Name other two limiting factors in this experiment.
Date posted: May 22, 2019. Answers (1)
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Date posted: May 22, 2019. Answers (1)
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a), What was the aim experiment?
b), Why was pyrogallic acid...(Solved)
In an experiment a group of students set up the test tubes as shown below
a), What was the aim experiment?
b), Why was pyrogallic acid included in the gas jar. A?
c), What results would you expect in each of the gas jar A and B at the end of experiment?
Date posted: May 22, 2019. Answers (1)
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Give an explanation why haemophilia is more common in males than in females.
Date posted: May 22, 2019. Answers (1)
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normal man. Let H represent gene for normal condition and...(Solved)
Haemophilia is a sex linked disorder due to a recessive gene. A carrier woman married a
normal man. Let H represent gene for normal condition and h to represent gene for
haemophilic condition.
a), State the genotypes of
i), Man
ii), woman
bi), Using a punnet square, show the genotypes of the children resulting from this
marriage
ii), State the probability of getting a carrier daughter.
Date posted: May 22, 2019. Answers (1)
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a), Name the parts labeled
K –
M –
b), State the functions of
P –
Q –
c) A...(Solved)
The diagram below shows some components of a light microscope.
a), Name the parts labeled
K –
M –
b), State the functions of
P –
Q –
c) A student was viewing a prepared slide of a plant cell under high power microscope.
The features of the cell were blurred. Which one of the labeled parts of the microscope
would the student use to obtain; A sharper outline of the features
Date posted: May 22, 2019. Answers (1)
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State two functions of ovaries in humans.
Date posted: May 22, 2019. Answers (1)
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a) Identify the stage of cell division in which this phenomenon occurs.
b) State the...(Solved)
The diagram below shows a phenomenon which occurs during cell division.
a) Identify the stage of cell division in which this phenomenon occurs.
b) State the importance of the phenomenon taking place in the part labeled B.
Date posted: May 22, 2019. Answers (1)
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Date posted: May 22, 2019. Answers (1)
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Date posted: May 22, 2019. Answers (1)
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(a) Why does the activity of the enzyme become constant after a while?
(b) State how the activity...(Solved)
Use the graph below to answer the following questions.
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(b) State how the activity of the enzyme may be increased in (a) above.
Date posted: May 22, 2019. Answers (1)
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Date posted: May 22, 2019. Answers (1)
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Date posted: May 22, 2019. Answers (1)
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(a) State the function of the organelle drawn above.
(b) Name the parts of the organelle where :
(i) Oxygen...(Solved)
Below is a diagram of an organelle.
(a) State the function of the organelle drawn above.
(b) Name the parts of the organelle where :
(i) Oxygen gas is produced as a byproduct.
(ii) Carbon (IV) oxide is utilized.
Date posted: May 22, 2019. Answers (1)
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follow.
a)Name the class in which the plant belongs.
b)...(Solved)
The diagram below represents a transverse section of a plant part. Study it and answer the questions that
follow.
a)Name the class in which the plant belongs.
b) Give a reason for answer (a) above.
c) State one adaptation for the structures labeled X to their functions.
Date posted: May 22, 2019. Answers (1)
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Date posted: May 22, 2019. Answers (1)
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(i) B1
(ii) B2
(iii)B6(Solved)
State the deficiency diseases of each of the following vitamins.
(i) B1
(ii) B2
(iii)B6
Date posted: May 22, 2019. Answers (1)
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Name the substance U, V and W.(Solved)
Study the flow diagram below.
Name the substance U, V and W.
Date posted: May 22, 2019. Answers (1)
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When red blood cell was placed in a certain solution, the solution exerted more osmotic pressure
leading to...(Solved)
In a certain experiment, the following observation was made:
When red blood cell was placed in a certain solution, the solution exerted more osmotic pressure
leading to the cell losing water molecules to become crenated/ shrunk.
(a) What type of solution was the cell placed in respect to the cell’s cytoplasm?
(b) By which physiological process did the cell lose water molecules?
Date posted: May 22, 2019. Answers (1)
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Under what condition is lactic acid formed in human muscles?
Date posted: May 22, 2019. Answers (1)