Can you think of reasons why more complex organisms cannot give rise to new individuals through regeneration?
Complex organisms are not simply a random collection of cells where sPecialized cells are organised as tissues, and tissues ale organised into organs which then have to be placed at definite positions in the body. In such a carefully organised situation, it is not easy to develop organism through regeneration.
How are the modes for reproduction different in unicellular and multicellular organisms ?
List two advantages of practising vegetative propagation in plants. Select two plants raised by this method from the list given below:
Banana, Gram, Pea, Rose, Tomato, Wheat.
Differentiate between ‘self-pollination’ and ‘cross-pollination’. Describe double fertilisation in plants.
What is AIDS? Which microbe is responsible for AIDS infection? State one mode of transmission of this disease. Explain in brief one measure for the prevention of AIDS.
What is the effect of DNA copying which is not perfectly accurate on the reproduction process?
What is reproduction? What are its two types? Which one of the two confers new characteristics on the offsprings and how?
State in brief the changes that take place in a fertilised egg (zygote) till birth of the child in the human female reproductive system. What happens to the egg when it is not fertilised?
(a) Name the parts labelled A, B, C, D and E.
(b) Where do the following functions occur?
(i) Production of an egg
(ii) Fertilisation
(iii) Implantation of zygote.
(c) What happens to the lining of uterus:
(i) before release of a fertilised egg?
(ii) if no fertilisation occurs?
List the parts of human male reproductive system which contribute fluid to the semen. State two advantages semen offers to the sperms.
State one genetically different feature between sperms and eggs of humans. What is its consequence?
Name the two types of germ-cells present in human beings. How do they structurally differ from each other? Give two differences.
What are sexually transmitted diseases?
Name four such diseases. Which one of them damages the immune system of human body?
If a woman is using a copper-T will it help in protecting her from sexually transmitted diseases?
Asexual reproduction takes place through budding in :
(a) Amoeba
(b) Yeast
(c) Plasmodium
(d) Leishmania.
Which of the following is not a pan Of the female reproductive system in human beings ?
(a) Ovary
(b) Uterus
(c) Vas deferens
(d) Fallopian tube
“Variations that confer an advantage to an individual organism only will survive in a population.” Justify.
Name the information source of making proteins in the cell. State two basic events in reproduction.
What is regeneration? State a reason why a more complex organism cannot give rise to new individuals through this method.
(a) Explain the terms:
(i) Implantation (ii) Placenta
(b) What is the average duration of human pregnancy?
What does HIV stand for? Is AIDS an infectious disease? List any four modes of spreading AIDS.
a) List any four reasons for adopting contraceptive methods.
(b) If a woman is using Copper-T, will it help in protecting her from sexually transmitted diseases? Why?