Tag: modes of reproduction

Questions Related to modes of reproduction

Select the correct option:

On very special feature in the earthworm is that:

botany modes of reproduction fertilization in organisms sexual reproduction in organisms reproduction in organisms

  1. fertilization of eggs occurs inside the body

  2. the typhlosole greatly increases the effective absorption area of intestine

  3. the S-shaped setae embedded in the integument are the defensive weapons used against the enemies

  4. it has a long dorsal tubular heart.

Show answer
Correct Option: B
Explanation:

From 27th segment upt 23-25 segments in front of the anus in intestine of earthworm, lies a highly glandular and vascular part called typhosole. It greatly increases the effective absorption area for digested food in the intestine.

Given below are a few statements related to external fertilisation. Choose the correct statements.
(i) The male and female gametes are formed and released simultaneously.
(ii) Only a few gametes are released into the medium.
(iii) Water is the medium in a majority of organisms exhibiting external fertilisation.
(iv) Offspring formed as a result of external fertilisation have better chance of survival than those formed inside an organism.

botany modes of reproduction fertilization in organisms sexual reproduction in organisms reproduction in organisms

  1. (iii) and (iv)

  2. (i) and (iii)

  3. (ii) and (iv)

  4. (i) and (iv)

Show answer
Correct Option: B

Mark the correct one.

botany modes of reproduction fertilization in organisms sexual reproduction in organisms reproduction in organisms

  1. Labeo- Internal fertilization

  2. Frog - Internal fertilization

  3. Birds - External fertilization

  4. Balaenoptera - internal fertilization

Show answer
Correct Option: D
Explanation:
  • Balaenoptera which designates genus is a combination of two Latin words, Balaena (meaning whale) and "pteron" (meaning fin). It thus means a whale having a dorsal fin so as to distinguish from Balaena (meaning whale without dorsal fin). "Musculus" designating species is a Latin word originally meaning a "mouse.
  • In mammals, reptiles, birds, and some types of fish the gametes meet inside of the female's body. This is called internal fertilization. 
  • As Balaenoptera is a mammal the fertilization in Balaenoptera is internaL.
  • so, the correct answer is  'Balaenoptera - internal fertilization'.

Fertilization is

botany modes of reproduction fertilization in organisms sexual reproduction in organisms reproduction in organisms

  1. Union of diploid spermatozoon with diploid ovum to form diploid zygote.

  2. Union of haploid sperm with haploid ovum to form haploid zygote.

  3. Union of haploid sperm with haploid ovum to form diploid zygote.

  4. Union of diploid sperm with haploid ovum to form triploid zygote.

Show answer
Correct Option: C
Explanation:

Sexual reproduction in animals involves the production and fusion of two types of gametes (haploid cells) sperm and eggs. Typically, two different individuals are required. A male parent contributes sperm, and a female parent contributes an egg, or ovum. The sperm provides genes coding for some of the male parents traits, and the egg contributes genes coding for some of the female parents traits. The egg is typically large and nonmotile, with a store of nutrients that supports the development of the embryo. The sperm is usually small and motile and adapted to propel itself by beating its long, whip like flagellum. When sperm and egg unite, a (diploid) zygote, or fertilized egg, is produced. The zygote develops into a new animal, similar to both parents but not identical to either. Sexual reproduction typically involves remarkably complex structural, functional, and behavioural processes. In vertebrates, hormones secreted by the hypothalamus, pituitary gland and gonads regulate these processes.

When gamete fusion is involved in the formation of new organism the phenomenon is known as

botany modes of reproduction fertilization in organisms sexual reproduction in organisms reproduction in organisms

  1. Syngamy

  2. External fertilization

  3. Parthenogenesis

  4. Parthenocarpy

Show answer
Correct Option: A
Explanation:

Syngamy is a process in sexual reproduction that is defined as the fusion of the male gamete i.e., sperm with the female gamete i.e., egg resulting in the formation of a diploid zygote. Thus the correct answer is option A.

Isogamy is found in

botany modes of reproduction fertilization in organisms sexual reproduction in organisms reproduction in organisms

  1. Hydra

  2. Monocystis

  3. Plasmodium

  4. Planaria

Show answer
Correct Option: B
Explanation:

The fusion of similar motile gametes is known as isogamous. Monocystis is an endoparasite in the seminal vesicle and coelom of earthworms. Fusing gametes do not differ morphologically but may be different physiologically. The isogamous gametes fuses to form zygote which develops into sporoblast, sporocyst, trophozoite and finally, to young trophozoite.

So, the correct answer is option B.

In sexual reproducing animals, the union of male and female gamete forms a cell, which is called as

botany modes of reproduction fertilization in organisms sexual reproduction in organisms reproduction in organisms

  1. Ovarian cell

  2. Oocyte

  3. Zygote

  4. Graafian follicle

Show answer
Correct Option: C
Explanation:

Ovarian cell is the cells of ovary.
Oocyte is the female gametocyte or germ cell. It is involved in reproduction.
Zygote is the diplod cell, formed by the fusion of two gametes i.e., by the fusion of male gamete (sperm) or female gamete (ovum).
Graafian follicle is the mature follicle in the ovary of mammals. It contains cavity, which is filled by liquid and it ruptures during ovulation to release ovum.
Thus, the correct answer is option C.

In oogamy fertilisation involves,

botany modes of reproduction fertilization in organisms sexual reproduction in organisms reproduction in organisms

  1. A small non-motile female, gamete and large motile male gamete

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

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

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

Show answer
Correct Option: B
Explanation:

In oogamy, fertilization involves the fusion of a large non-motile female gamete and a small motile male gamete. The large motile female gamete is the ovum which is produced in the ovary. The ovum after maturation is released from the ovary under the influence of LH hormone. The small motile male gametes are known as sperm which is produced in the testis. The two dissimilar gametes fuse to form a diploid zygote by the process of syngamy.

So, the correct answer is option B.

Fusion of dissimilar gametes is

botany modes of reproduction fertilization in organisms sexual reproduction in organisms reproduction in organisms

  1. Allogamy

  2. Dichogamy

  3. Autogamy

  4. Fertilization

Show answer
Correct Option: D
Explanation:
Cross-pollination in a crop plant is known as allogamy. Allogamy is defined as fertilization of ovum of a flower by the pollen of another flower on the different plant. The pollen is transferred from the anther of a male flower to the stigma of a female flower. Allogamy takes place because of the male and female part of a particular flower mature at a different time. 
Dichogamy is a condition when the stamens and pistils of a flower mature at different times to prevent self-fertilization.
Autogamy is the phenomena of fusion of gametes produced from the same individual. It involves the transfer of pollen from the anther to the stigma of the same flower. It is avoided when the number of seed is less, or the produced pollen is not able to fuse and germinate with the ovule of the same flower or the produced pollen are not healthy. 
Fusion of dissimilar gametes is fertilization. It takes place during sexual reproduction where the male and female gametes fuse to form a zygote. 
So, the correct answer is option D.

Regarding fertilization which among the following statements is incorrect

botany modes of reproduction fertilization in organisms sexual reproduction in organisms reproduction in organisms

  1. It restores diploid condition in the zygote

  2. It activates egg both physiologically and metabolically

  3. Paternal and maternal sets contribute to the diploid number without causing any variation

  4. It determines the sex of the offspring

Show answer
Correct Option: C
Explanation:

The process of fusion between haploid male nucleus and egg nucleus is known as amphimixis. It is also known as syngamy. The process is known as fertilization which leads to formation of a diploid zygote and restores diploid condition in zygote. The statement is true.

Fertilization activates the egg physically and leads to formation of fertilization cone to prevent polyspermy. It also brings changes in permeability. The eggs become metabolically active and allows division of nucleus and forms embryo. The statement is true.
Sexual reproduction leads to the recombination of character in the pachytene stage of the meiosis which causes variation. So, the statement is false.

Fertilization determines the sex. Men have an X and a Y. So, each of their sperm carries one of the 2 sex chromosomes, which sex chromosome is in the sperm that fertilizes the egg dictates the baby's sex. The statement is true.

So, the correct answer is option C.