How do organisms reproduce Worksheet-15

How do organisms reproduce Worksheet-15

 

Subjective questions:

  1. What criteria and precautions should be taken into consideration while selecting stock and scion?

 

  1. Describe how vegetative propagation is done in the following plants :

(a) Ginger          (b) Sugarcane   (c) Citrus           (d) Bryophyllum

 

  1. Explain the main characters of self-pollinated plants.

 

  1. Explain the method of vegetative reproduction in mint, sweet potato, Dahlia, onion and Chrysanthemum.

 

  1. What is fission? What are the different types of fission? Explain them with the help of diagrams.

 

  1. Write a note on fertilisation in human beings.

 

  1. Describe how sexual reproduction is a necessity for evolution.

 

  1. Enumerate the events of female menstrual cycle starting from the maturation of a group of follicles.

 

  1. Define grafting. Suggest any two advantages and disadvantages of grafting.

 

  1. "DNA copies generated will be similar, but may not be identical to the original." Explain.

 

  1. Why is variation of organisms important? Give an example.

 

  1. What changes are noticed on sexual maturity of human beings?

 

  1. Mention the important post-fertilisation changes in the flower.

 

  1. Define secondary sex characters. Give three examples each in male and female.

 

  1. What is grafting? Write any two uses of this process.

 

  1. (i) Mention the various methods used to prevent pregnancy. Give one example of each.

(ii) Why is it done so?

 

  1. How can the reproductive health be maintained and sexually transmitted diseases (STD) prevented?

 

  1. What is a seed? How does it help in reproduction in plants?

 

  1. Define the term layering. What are its two types? How is one different from the other?

 

  1. What role do hormones play in the process of reproduction?

 

  1. How does binary fission differ from multiple fission?

 

  1. Why is vegetative propagation practiced for growing some types of plants?

 

  1. Why is DNA copying an essential part of the process of reproduction?

 

  1. How is the process of pollination different from fertilisation?

 

  1. What are the advantages of sexual reproduction over asexual reproduction?

 

  1. Draw a labelled diagram of the longitudinal section of a flower.

 

  1. What are the different methods of contraception?

 

  1. How are the modes of reproduction different in unicellular and multicellular organisms?

 

  1. What could be the reasons for adopting contraceptive; methods?

 

  1. Draw the diagram of a flower to show its male and female reproductive parts. Label the following on it :

(i) Ovary            (ii) Anther          (iii) Filament    (iv) Stigma

What is the function of anther? How does fusion of male and female gametes take place in plants?