Identify the correct option (A), (B), (C), (D) with respect to spermatogenesis. [2024]
[IMAGE 13]
FSH, Leydig’s cells, Sertoli cells, Spermiogenesis
ICSH, Interstitial cells, Leydig’s cells, Spermiogenesis
FSH, Sertoli cells, Leydig’s cells, spermatogenesis
ICSH, Leydig’s cells, Sertoli cells, Spermatogenesis
(1)
Spermatogenesis starts at the age of puberty due to significant increase in the secretion of gonadotropin releasing hormone (GnRH). The increased levels of GnRH then acts at the anterior pituitary gland and stimulates the secretion of two gonadotropins – luteinising hormone (LH) and follicle stimulating hormone (FSH). LH acts at the Leydig's cells and stimulates the synthesis and secretion of androgens. Androgens, in turn, stimulate the formation of spermatids. FSH acts on the Sertoli cells and stimulates secretion of some factors which help in the process of spermiogenesis.
Given below are two statements regarding oogenesis. [2023]
Statement I: The primary follicles get surrounded by more layers of granulosa cells, a theca and shows fluid filled cavity antrum. Now it is called secondary follicle.
Statement II: Graafian follicle ruptures to release the secondary oocyte from the ovary by the process called ovulation.
In the light of the above statements, choose the correct answer from the options given below.
Statement I is correct but statement II is false.
Statement I is incorrect but statement II is true.
Both statement I and statement II are true.
Both statement I and statement II are false.
(2)
The primary follicles get surrounded by more layers of granulosa cells and a new theca and are called secondary follicles. The secondary follicle soon transforms into a tertiary follicle which is characterised by a fluid filled cavity called antrum.
Arrange the sequence of different hormones for their role during gametogenesis. [2023]
(A) Gonadotropin LH stimulates synthesis and secretion of androgen.
(B) Gonadotropin releasing hormone from hypothalamus.
(C) Androgen stimulates spermatogenesis.
(D) Gonadotropin FSH helps in the process of spermiogenesis.
(E) Gonadotropins from anterior pituitary gland.
Choose the correct answer from the options given below:
(E), (A), (D), (B), (C)
(C), (A), (D), (E), (B)
(B), (E), (A), (C), (D)
(D), (B), (A), (C), (E)
(3)
Spermatogenesis starts at the age of puberty due to significant increase in the secretion of a hypothalamic hormone, gonadotropin releasing hormone (GnRH). The increased levels of GnRH then act at the anterior pituitary gland and stimulates secretion of two gonadotropins – luteinising hormone (LH) and follicle stimulating hormone (FSH). LH acts at the Leydig cells and stimulates synthesis and secretion of androgens. Androgens, in turn, stimulate the process of spermatogenesis. FSH acts on the Sertoli cells and stimulates secretion of some factors which help in the process of spermiogenesis.
Given below are two statements: [2022]
Statement I: The release of sperms into the seminiferous tubules is called spermiation.
Statement II: Spermiogenesis is the process of formation of sperms from spermatogonia.
In the light of the above statements, choose the most appropriate answer from the options given below.
Both Statement I and Statement II are correct
Both Statement I and Statement II are incorrect
Statement I is correct but Statement II is incorrect
Statement I is incorrect but Statement II is correct
(3)
Formation of mature spermatozoa from spermatids is called spermiogenesis. Spermiation is the process by which mature spermatids are released from Sertoli cell into the seminiferous tubule lumen prior to their passage to the epididymis.
Which of the following statements are true for spermatogenesis but do not hold true for oogenesis? [2022]
(A) It results in the formation of haploid gametes.
(B) Differentiation of gamete occurs after the completion of meiosis.
(C) Meiosis occurs continuously in a mitotically dividing stem cell population.
(D) It is controlled by the Luteinising Hormone (LH) and Follicle Stimulating Hormone (FSH) secreted by the anterior pituitary.
(E) It is initiated at puberty.
Choose the most appropriate answer from the options given below:
(A) and (E) only
(B) and (C) only
(B), (D) and (E) only
(B), (C) and (E) only
(4)
In both, spermatogenesis and oogenesis haploid gametes are formed. The spermatids are transformed into spermatozoa (sperms) by the process called spermiogenesis occurs in process spermatogenesis only. Spermatogenesis and oogenesis both are controlled by LH and FSH secreted by the anterior pituitary. Spermatogenesis is a continuous process that begins at puberty. Oogenesis on the other hand begins during embryonic development of the female.
At which stage of life the oogenesis process is initiated? [2022]
Puberty
Embryonic development stage
Birth
Adult
(2)
Oogenesis is initiated during embryonic development stage when a couple of million oogonia are formed within each fetal ovary. No oogonia are formed or added after birth.
Meiotic division of the secondary oocyte is completed [2020]
prior to ovulation
at the time of copulation
after zygote formation
at the time of fusion of a sperm with an ovum
(4)
In humans, the secondary oocyte is produced when the primary oocyte grows in size and completes its first meiotic division. The secondary oocyte will be halted at this stage of metaphase of meiosis II until fertilisation takes place. Thus, when a sperm cell fertilises the female sex cell, the secondary oocyte rapidly completes the remaining stages of meiosis II, giving rise to ovum, with which the sperm cell unites.
The difference between spermiogenesis and spermiation is [2018]
In spermiogenesis spermatids are formed, while in spermiation spermatozoa are formed
In spermiogenesis spermatozoa are formed, while in spermiation spermatids are formed
In spermiogenesis spermatozoa from Sertoli cells are released into the cavity of seminiferous tubules, while in spermiation spermatozoa are formed
In spermiogenesis spermatozoa are formed, while in spermiation spermatozoa are released from Sertoli cells into the cavity of seminiferous tubules.
(4)
Formation of spermatozoa from spermatids is called spermiogenesis. After spermiogenesis, sperm heads become embedded in the Sertoli cells and are finally released from the seminiferous tubules by the process called spermiation.
Which of the following layers in an antral follicle is acellular? [2015]
Stroma
Zona pellucida
Granulosa
Theca interna
Which of the following cells during gametogenesis is normally diploid? [2015]
Spermatogonia
Secondary polar body
Primary polar body
Spermatid
(1)
Spermatogonia are diploid cells which mature into primary spermatocytes (2n) by growth. They then produce two haploid secondary spermatocytes by meiosis I. Each secondary spermatocyte (n) completes the meiosis II and produces two spermatids (n). Each spermatid (n) develops into a spermatozoan or sperm (n).
