REPRODUCTION QUICK QUIZ FORM THREE

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1. What is the significance of reproduction. (2m)2 

2. Distinguish between sexual and asexual reproduction. (2m)4
Sexual
Asexual 

3. (a) What is crossing over. (1m)5
(b)What is its significance. (1m)6
(c) Name two organs in humans where crossing over takes place. (2m)8 

4. A chromosome is a long thread like structure made up of long molecules of DNA wrapped around proteins.
(a)DNA is an abbreviation. What’s the long form of DNA. (1m)9
(b) What is the name the proteins in the above excerpt. (1m)10

5. Distinguish between the following terminologies.(2m)12
(i)Haploid
(ii)Diploid

6. (a)State and explain four ways by which flowering plants prevent self pollination and promote cross pollination. (8m)20
(i)
(ii)
(iii)
(iv)
(b) What is the advantage of cross pollination over self pollination. (2m)22

7. Distinguish between: (8m)30
(a) Apocarpous and syncarpous flowers.
(b) Complete and incomplete flower.
(c) Regular and irregular flower.
(d) Superior and inferior ovary.
THE END

1.      What is the significance of reproduction. (2m)2
-Propagation of a species
-Variation hence improvement of a species. 

2. Distinguish between sexual and asexual reproduction. (2m)4
Sexual
-Involves fusion of gametes Asexual
-No fusion of gametes
3. (a) What is crossing over. (1m)5
-Exchange of genetic material between non-sister chromatids of homologous chromosomes
(b)What is it’s significance. (1m)6
-Is a source of variation (c) Name two organs in humans where crossing over takes place. (2m)8
-Ovary
-Testis

4. A chromosome is a long thread like structure made up of long molecules of DNA wrapped around proteins.
(a)DNA is an abbreviation. What’s the long form of DNA. (1m)9
-Deoxyribonucleic Acid (b) What is the name the proteins in the above excerpt. (1m)10
-Histones
5. Distinguish between the following terminologies.(2m)12
(i)Haploid
-Having a single set of chromosomes (ii)Diploid
-Having two sets of chromosomes.
6. (a)State and explain four ways by which flowering plants prevent self pollination and promote cross pollination. (8m)20
(i) Protandry; Stamens mature before pistils of the same flower/plant making self pollination impossible
(ii) Protogyny; Pistils mature before stamens of the same flower/plant hence self pollination is impossible.
(iii) Dioecism; Male and female reproductive organs are on separate plants of the same species making self pollination virtually impossible.
(iv) Heterostyly; A condition of having unequal styles and filaments among flowers in a cluster thus increasing chances of cross pollination.
NB: Any other relevant answer.

(b) What is the advantage of cross pollination over self pollination. (2m)22
-Mixing of genetic material between the different plants of the same species leading to variation hence improvement of a species.

7. Distinguish between: (8m)30
(a) Apocarpous and syncarpous flowers.
-Apocarpous: Carpels are free/not joined/United. Owtte
-Syncarpous: Carpels are fused.
(b) Complete and incomplete flower.
-Complete: Having all the four floral parts.
-Incomplete: Missing one or more of the four floral parts.
(c) Regular and irregular flower.
-Regular: Having radial symmetry
-Irregular: Having bilateral symmetry
(d) Superior and inferior ovary.
-Superior: Floral parts of a flower are attached at a point below the position of the ovary.
-Inferior:Floral parts of a flower are attached at a point above the position of the ovary
THE END

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