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प्रश्न
Draw a well labelled diagram of T.S. anther.
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संबंधित प्रश्न
What is DNA?
How does the amount of DNA remain constant though each new generation is a combination of DNA copies of two individuals?
Egg laid after fertilisation is made up of a single cell.
Match items in Column I with those in Column II:
| Column I | Column II | ||
| (a) | Bud | (i) | Maple |
| (b) | Eyes | (ii) | Spirogyra |
| (c) | Fragmentation | (iii) | Yeast |
| (d) | Wings | (iv) | Bread mould |
| (e) | Spores | (v) | Potato |
| (vi) | Rose |
Which life process ensures that a plant or animal species will not disappear from this earth?
Fill in the following blank with suitable word :
the process of...........ensures continuity of life on earth.
What is a clone? Why do offsprings formed by asexual reproduction exhibit remarkable similarity?
Reproduction is essential for living organisms in order to ______
What type of fertilisation takes place in birds?
State whether the following statement is true (T) or false (F):
Dogs and cats reproduce from two parents.
Bryophyllum can reproduce by its ______.
Answer the following question.
The growing size of the human population is a cause of concern for all people. The rate of birth and death in a given population will determine its size. Reproduction is the process by which organisms increase their population. The process of sexual maturation for reproduction is gradual and takes place while general body growth is still going on. Some degree of sexual maturation does not necessarily mean that the mind or body is ready for sexual acts or for having and bringing up children. Various contraceptive devices are being used by human beings to control the size of the population.
(a) List two common signs of sexual maturation in boys and girls.
(b) What is the result of reckless female foeticide?
(c) Which contraceptive method changes the hormonal balance of the body?
(d) Write two factors that determine the size of a population.
Multiple choice question.
Which of these is the male reproductive organ in humans?
The number of meiotic and mitotic divisions necessary for development of female gametophyte in angiosperms is ______.
______ is an example of helobial endosperm.
Seminal fluid is ______ in nature.
Nebenkern is ______.
The average period of pregnancy in human lasts for ______ days of pregnancy.
In a flower, the parts that produce male and female gametes (germ cells) are
