Tag: fertilization in organisms

Questions Related to fertilization in organisms

Fertilization is depicted by which of the following condition? 

  1. n $\rightarrow$ 2n

  2. 2n $\rightarrow$ 3n

  3. 2n $\rightarrow$ 4n

  4. 4n $\rightarrow$ 8n


Correct Option: A
Explanation:

Fertilization is the process of fusion of male and female gametes. Gametes are haploid (n) in nature and the fusion of the two results in the diploid (2n) product called as zygote. Zygote is the universal diploid cell. 

Thus, the correct answer is option A.

Oogamous sexual reproduction involves fusion of

  1. Motile and non-motile gametes

  2. Similar gametes

  3. Dissimilar motile gametes

  4. Dissimilar non-motile gametes


Correct Option: A
Explanation:

Oogamous reproduction involves fusion of one motile male gamete and another non-motile large sized female gametes. 

Fusion of similar gametes is known as isogamous reproduction. Fusion of dissimilar motile or non-motile gametes is known as anisogamous reproduction.
So, the correct option is 'Motile and non-motile gametes'.

In oogamy, fertilization occurs between

  1. Small non-motile female gamete and large motile male gamete.

  2. Large non-motile female gamete and small motile male gamete.

  3. A large non-motile female gamete and a small non-motile male gamete.

  4. A large motile female gamete and a small non-motile male gamete.


Correct Option: B
Explanation:

Oogamy is a form of sexual reproduction. It is a form of anisogamy (heterogamy) in which the female gamete is significantly larger than the male gamete and is non-motile.The male gametes are  smaller in size and motile 
So, the correct option is 'Large non-motile female gamete and small motile male gamete'.

Fusion of a male gamete with egg in embryo sac is

  1. Autogamy

  2. Syngamy

  3. Double fertilization

  4. Triple fusion


Correct Option: B
Explanation:

Syngamy and triple fusion are two events of sexual reproduction in plants. Syngamy is the fusion of one of the male gamete with the egg cell to produce a zygote while In triple fusion, second male gamete fuses with two polar nuclei to produce primary endosperm nucleus.

Since two types of fusions, syngamy and triple fusion take place in an embryo sac the phenomenon is termed double Fertilisation.
So, the correct answer is 'Syngamy'.

The phenomenon of endogamy is reported in

  1. Fasciola

  2. Earthworm

  3. Marchantia

  4. Rabbit


Correct Option: A
Explanation:

Fasciola is a genus of trematodes. It is commonly known as liver fluke. It shows the phenomena of endogamy where the two fusing gametes are derived from the same parent which means the gametes are uniparental. These are hermaphrodite and has both male and female reproductive organs. The male and female reproductive organs open up into the same chamber within the body, which is called the genital atrium where the two gametes fuses.

So, the correct answer is option A.

The type of syngamy in Trichonympha is

  1. Hologamy

  2. Anisogamy

  3. Isogamy

  4. Conjugation


Correct Option: A
Explanation:

The process of fusion between the haploid male nucleus and egg nucleus is known as amphimixis. It is also known as syngamy. It leads to the formation of a diploid zygote. The form of sexual reproduction in which the gametes are of the same size and structure as the somatic cells. Trichonympha lives in the intestine termite species and helps them to break the cellulose which they take from the wood. They produce similar haploid gametes known as zooflagellates so it is classified as hologamy.

So, the correct answer is option A.

Fertilisation was first discovered by

  1. Aristotle

  2. Leeuwenhoek

  3. Harvey

  4. Pander


Correct Option: A
Explanation:

Fertilization is the fusion of male and female gametes. In animals, it was first discovered by Aristotle. In plants, it was discovered by Nawaschin.

Which of the following is incorrect about fertilization?

  1. It restores diploid condition.

  2. It activates egg.

  3. There is no variation.

  4. It determines sex of offspring.


Correct Option: C
Explanation:

As the sperm reaches ovum to fertilize it, the ovum gets activated and completes its second meiotic division. After fertilization, a diploid zygote is formed. Fertilization also helps in determining the sex of the offspring. On the one hand, it leads to inherent qualities of a parent and on the other hand, it is the means for variations among the populations.

So, the correct option is 'There is no variation'.

Union between a large non-motile female gamete and a small motile male gamete is called ____________.

  1. Anisogamy

  2. Isogamy

  3. Oogamy

  4. Zoogamy


Correct Option: A

Male and female, both gametes arise from the same parent in

  1. Rabbit

  2. Humans

  3. Taenia

  4. None of the above


Correct Option: C
Explanation:
A. Rabbit is a monosexual animal. Male gametes are produced by male rabbit and female gametes are produced by a female rabbit.
B. In humans, females produce eggs and males produce sperms. These gametes fuse to produce a new organism. 
C. Taenia, commonly known as Tapeworm, is a hermaphrodite organism. Each segment of a tapeworm, which is known as proglottid, consists of male and female reproductive systems.
Hence, both male and female gametes arise from the same parent in Taenia, as it is a hermaphrodite. So, the correct answer is 'taenia'.