1. Zoospore:- 1. A zoospore is a motile asexual spore that utilizes the flagella for movement. 2. It is an asexual reproductive structure. Zygote:- 1. A zygote is a non-motile diploid cell formed as a result of fertilization. 2. It is formed as a result of sexual reproduction. For more answers visit toRead more

    Zoospore:-
    1. A zoospore is a motile asexual spore that utilizes the flagella for movement.
    2. It is an asexual reproductive structure.
    Zygote:-
    1. A zygote is a non-motile diploid cell formed as a result of fertilization.
    2. It is formed as a result of sexual reproduction.

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  2. External fertilization is the process in which the fusion of the male and the female gamete takes place outside the female body in an external medium, generally water. Fish, frog, starfish are some organisms that exhibit external fertilization. Disadvantages of external fertilization:- In external fRead more

    External fertilization is the process in which the fusion of the male and the female gamete takes place outside the female body in an external medium, generally water.
    Fish, frog, starfish are some organisms that exhibit external fertilization.

    Disadvantages of external fertilization:-
    In external fertilization, eggs have less chances of fertilization. This can lead to the wastage of a large number of eggs produced during the process.
    Further, there is an absence of proper parental care to the offspring, which results in a low rate of survival in the progenies.

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  3. Meiosis is a process of reductional division in which the amount of genetic material is reduced. Gametogenesis is the process of the formation of gametes. Gametes produced by organisms are haploids (containing only one set of chromosomes), while the body of an organism is diploid. Therefore, for proRead more

    Meiosis is a process of reductional division in which the amount of genetic material is reduced. Gametogenesis is the process of the formation of gametes. Gametes produced by organisms are haploids (containing only one set of chromosomes), while the body of an organism is diploid. Therefore, for producing haploid gametes (gametogenesis), the germ cells of an organism undergo meiosis. During the process, the meiocytes of an organism undergo two successive nuclear and cell divisions with a single cycle of DNA replication to form the haploid gametes.

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  4. Although sexual reproduction involves more time and energy, higher organisms have resorted to sexual reproduction in spite of its complexity. This is because this mode of reproduction helps introduce new variations in progenies through the combination of the DNA from two (usually) different individuRead more

    Although sexual reproduction involves more time and energy, higher organisms have resorted to sexual reproduction in spite of its complexity. This is because this mode of reproduction helps introduce new variations in progenies through the combination of the DNA from two (usually) different individuals. These variations allow the individual to cope with various environmental conditions and thus, make the organism better suited for the environment. Variations also lead to the evolution of better organisms and therefore, provide better chances of survival. On the other hand, asexual reproduction does not provide genetic differences in the individuals produced.

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  5. (a) Juvenile phase:- It is the period of growth in an individual organism after its birth and before it reaches reproductive maturity. (b) Reproductive phase:- It is the period when an individual organism reproduces sexually. (c) Senescent phase:- It is the period when an organism grows old and loseRead more

    (a) Juvenile phase:- It is the period of growth in an individual organism after its birth and before it reaches reproductive maturity.
    (b) Reproductive phase:- It is the period when an individual organism reproduces sexually.
    (c) Senescent phase:- It is the period when an organism grows old and loses the ability to reproduce.

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