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i) - Red blood cells have respiratory pigment for transport of oxygen.
- Have biconcave shape to increase surface area for diffusion of respiratory gases (oxygen and carbon (IV) oxide; )
- Are pliable to be able to squeeze within narrow blood capillaries.
- Lack nucleus and some other organelles for packaging of more haemoglobin;
- Have thin epithelium for easy diffusion of respiratory gases;
- Are many per unit volume for transport of more oxygen;
- Have enzyme carbonic anhydrase which speeds loading and offloading of carbon (IV) oxide.
- Have a relatively long life span for efficient transport of oxygen;
ii) White blood cells.
- Have nucleus to regulate cell activities as they destroy pathogens;
- Are able to change shape to be able to engulf and destroy pathogens; / are phagocytic to destroy pathogens;
- Are produced in small numbers to prevent them from destroying other cells;
- Produce opsonins / lysins /antitoxins / agglutinins which destroy pathogens / microbes
sharon kalunda answered the question on May 23, 2019 at 13:24
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Date posted: May 23, 2019. Answers (1)
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a) What...(Solved)
In an experiment to investigate an aspect of digestion, two test tubes A and B were set up as shown in the diagram below.
The test tubes were left in the bath for 30 minutes. The contents of each test tube was then tested for starch using iodine solution.
a) What was the aim of the experiment?
b) What results were expected in test tube A and B.
c) Account for the results you have given in (b) above in test tube A and B.
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Date posted: May 23, 2019. Answers (1)
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b) State THREE adaptation of part Q...(Solved)
The diagram below represents a mammalian embryo and associated maternal structures.
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b) State THREE adaptation of part Q to its functions.
c) i) Name the part labelled T.
ii) What is the function of part T?
Date posted: May 23, 2019. Answers (1)
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ii) Give...(Solved)
The diagram below represents a food web in a certain ecosystem.
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ii) Give a reason for your answer in a(i) above.
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ii) Quaternary consumer
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Date posted: May 23, 2019. Answers (1)
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a) State the couple's genotypes.
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Date posted: May 23, 2019. Answers (1)
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Date posted: May 23, 2019. Answers (1)
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Date posted: May 23, 2019. Answers (1)
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Date posted: May 23, 2019. Answers (1)
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Date posted: May 23, 2019. Answers (1)
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