a) R -retina
S- optic nerve
T- ciliary muscles
b) U -Has dark pigments to absorb stray lights and prevent internal reflections within the eyes.
-contains numerous blood vessels that supply nutrients to the eye and remove metabolic wastes from the eyes.
c) The radial muscles of the iris contract and the circular muscles relax; Pupils size (diameter) increases/ enlarges and more light
enters the eye.
sharon kalunda answered the question on September 16, 2019 at 07:17
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(a) Identify the tissue
(b) Name the cells represented by R,S and T
(c) State the function of structure S and R.
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Date posted: September 16, 2019. Answers (1)
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Date posted: September 16, 2019. Answers (1)
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Date posted: September 16, 2019. Answers (1)
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(iii) Worms feed on insect larvae;
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(vi) Large fish feed on small fish.
(a) From this record of observations, construct a food web.
(b) From the food web, isolate and write down a food chain that ends with:-
(i) Bird species as a secondary consumer.
(ii) Large fish as a tertiary consumer.
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Date posted: September 16, 2019. Answers (1)
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Date posted: September 13, 2019. Answers (1)
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Date posted: September 13, 2019. Answers (1)
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KEY
1. a) Jointed legs present ………………………………………………………………go to 2
b) Jointed legs absent………………………………………………………………..go to 7
2. a) Three pairs of legs ………………………………………………………………..go to 3
b) More than 3 pairs of legs………………………………………………………….go to 5
3. a) Wings present …………………………………………………………………….go to 4
b) Wings absent………………………………………………………………………Anoplura
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b) Two pairs of wings……………………………………………………………Hymenoptera
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b) More than ten pairs of legs ………………………………………………………. go to 6
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Date posted: September 13, 2019. Answers (1)
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Date posted: September 13, 2019. Answers (1)
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Date posted: September 13, 2019. Answers (1)
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Date posted: September 13, 2019. Answers (1)
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(b) Identify the structures labelled in the diagram that will develop into the following after fertilization.
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(i) C
(ii) D
Date posted: September 13, 2019. Answers (1)
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Date posted: September 13, 2019. Answers (1)