Test: Human Reproduction - NEET MCQ

• Male accessory glands secrete seminal plasma. A pair of seminal vesicles, bulbourethral glands, and a prostate gland are among the male accessory glands.
• Seminal plasma is made up of secretions from these glands and is high in fructose, calcium, and enzymes.
• It is the fluid part of the sperm-ejaculated.  
• It aids in the movement of sperm from the testes to the female genital tract.

Hence, the correct option is A.

NCERT Reference: topic “THE MALE REPRODUCTIVE SYSTEM” of chapter: Human Reproduction.

• Each testis contains about 250 compartments called testicular lobules.
• Each testicular lobule contains one to three highly coiled seminiferous tubules that produce sperms.

Fig: Image showing testicular lobules consists of seminiferous tubules. 

Hence, the correct option is D.

NCERT Reference: topic “THE MALE REPRODUCTIVE SYSTEM” of chapter: Human Reproduction.

Each seminiferous tubule is lined on its inside by two types of cells called male germ cells (spermatogonia) and Sertoli cells.The male germ cells undergo meiotic divisions finally leading to sperm formation, while Sertoli cells provide nutrition to the germ cells. The regions outside the seminiferous tubules called interstitial spaces, contain small blood vessels and interstitial cells or Leydig cells . Leydig cells synthesise and secrete testicular hormones called androgens. Other immunologically competent cells are also present.

Fig: Sertoli cells with embedded sperms

Hence, the correct option is .
NCERT Reference: Topic “THE MALE REPRODUCTIVE SYSTEM” of chapter: Human Reproduction.

The regions outside the seminiferous tubules called interstitial spaces, contain small blood vessels and interstitial cells or Leydig cells Leydig cells synthesise and secrete testicular hormones called androgens. Other immunologically competent cells are also present

Hence, the correct option is B.
NCERT Reference: topic “THE MALE REPRODUCTIVE SYSTEM” of chapter: Human Reproduction .

• Mitochondria are known as the cell's powerhouse, and the middle component of sperm contains a high number of them.
• Mitochondria provides  energy required by Sperms for active motility.

Structure of Sperm:

Hence, the correct option is B.
NCERT Reference: topic “GAMETOGENESIS ” of chapter: Human Reproduction .

The spermatids are transformed into spermatozoa (sperms) by the process 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.

Hence, the correct option is C.
NCERT Reference: topic “GAMETOGENESIS ” of chapter: Human Reproduction.

One primary oocyte will form one secondary oocyte and 1 polar body after meiosis 1. The polar body will give rise to 2 another polar bodies and 1 secondary oocyte will form one ovum without centrioles after meiosis 2. So, one oogonium will form 1 ovum without centrioles and 3 polar bodies.

• At puberty, the menstrual cycle begins in girls. The beginning of menstrual cycle is called menarche.
• It starts at the age of about 11 to 12 years in girls.

Hence, the correct option is C.

NCERT Reference: topic “MENSTRUAL CYCLE” of chapter: Human Reproduction.

• It is made almost exclusively in the placenta.
• hCG hormone levels found in the mother's blood and urine, rise a lot during the first trimester. 
• hCG Maintains the corpus luteum throughout the early stages of pregnancy. It is used to detect pregnancy.

Hence, the correct option is B.

NCERT Reference: topic “PREGNANCY AND EMBRYONIC DEVELOPMENT” of chapter: Human Reproduction.

• The release of ovum from ovary during menstrual cycle is called ovulation.
• Ovulation occurs in the middle of menstrual cycle that is on about 14th day of start of menstrual cycle.

Hence, the correct option is C.
NCERT Reference: topic “MENSTRUAL CYCLE” of chapter: Human Reproduction.

The menstrual flow results due to breakdown of endometrial lining of the uterus and its blood vessels which forms liquid that comes out through vagina. Menstruation only occurs if the released ovum is not fertilised every month till menopause.

Hence, the correct option is B.
NCERT Reference: topic “MENSTRUAL CYCLE” of chapter: Human Reproduction.

• The movement of the fetus is observed in the fifth month of pregnancy.
• In the first month heart is formed.
• In the second month limbs and digits are formed.
• At the end of three months, all major organs and genital organs are formed.

Hence, the correct option is C.
NCERT Reference: topic “PREGNANCY AND EMBRYONIC DEVELOPMENT” of chapter: Human Reproduction.

4 structure is implanted named Blastocyst.

The mitotic division starts as the zygote moves through the isthmus of the oviduct called cleavage towards the uterus  and forms 2, 4, 8, 16 daughter cells called blastomeres. The embryo with 8 to 16 blastomeres is called a morula.(Figure 3) The morula continues to divide and transforms into blastocyst  as it moves further into the uterus. The blastomeres in the blastocyst are arranged into an outer layer called trophoblast and an inner group of cells attached to trophoblast called the inner cell mass. The trophoblast layer then gets attached to the endometrium and the inner cell mass gets differentiated as the embryo. After attachment, the uterine cells divide rapidly and covers the blastocyst. As a result, the blastocyst becomes embedded in the endometrium of the uterus

• The head of mature mammalian sperm is made of elongated nucleus covered by acrosome.
• The acrosome is filled with hydrolytic enzymes that help in fertilization of ovum.
• These enzymes called sperm lysins that dissolve the membranes enveloping the ovum and help the sperm cell to enter the ovum by penetrating the egg membrane.

Hence, the correct option is C.

NCERT Reference: topic “GAMETOGENESIS” of chapter: Human Reproduction.

The mammary glands of the female undergo differentiation during pregnancy and start producing milk towards the end of pregnancy by the process called lactation.

Lactiferous glands present inside the mammary gland produce milk due to the release of the hormone oxytocin from pituitary glands.

Hence, the correct option is D.

NCERT Reference: topic “PARTURITION AND LACTATION” of chapter: Human Reproduction.

• After parturition, mammary glands start producing milk. The yellowish coloured milk is called colostrum.
• This milk contains antibodies that provide immunity to newly born baby.

Hence, the correct option is C.
NCERT Reference: topic “PARTURITION AND LACTATION” of chapter: Human Reproduction.

The correct sequence of spermatogenesis in the human testis is:

Spermatogonia: The precursor germ cells that divide mitotically.
Spermatocyte: These cells undergo meiosis; primary spermatocytes give rise to secondary spermatocytes.
Spermatid: Haploid cells that result from the second meiotic division.
Sperms: Mature sperm cells formed from the differentiation of spermatids.
Thus, the sequence is spermatogonia → spermatocyte → spermatid → sperms.
 

• Statement i is correct because oogenesis begins during embryonic development when oogonia are formed.
• Statement ii is incorrect because the primary oocyte does not complete its first meiotic division until puberty.
• Statement iii is correct; during the transition from primary to tertiary follicle, an antrum does develop.
• Statement iv is incorrect; at puberty, only 60,000-80,000 primary follicles remain, not 100,000.

Therefore, the correct statements are i and iii, making Option B the right answer.

- Statement i is correct because LH (Luteinizing Hormone) and FSH (Follicle-Stimulating Hormone) both peak around the 14th day of the menstrual cycle, which is known as ovulation.

- Statement ii is incorrect; the LH surge is responsible for the rupture of the Graafian follicle, leading to ovulation, not for the degeneration of the corpus luteum. The corpus luteum degenerates only in the absence of fertilization.

- Statement iii is correct; the corpus luteum secretes progesterone, which is crucial for maintaining the endometrium, making it suitable for implantation.

- Statement iv is also correct; if fertilization does not occur, the corpus luteum degenerates, leading to the disintegration of the endometrium and the onset of menstruation.

Therefore, the correct answer is C: i, iii, and iv.

- The Assertion is true because the male reproductive system does indeed include the testes, which are responsible for sperm production and hormone secretion.

- The Reason is also true, as Leydig cells do produce androgens, which play a crucial role in the development and maintenance of male reproductive tissues, including spermatogenesis.

- The Reason correctly explains the Assertion because the hormones produced by Leydig cells are vital for the processes mentioned in the Assertion.

- The Assertion is true because during each menstrual cycle, typically only one ovum is released from the ovary.

- The Reason is false; while ovarian hormones do influence the cyclical changes, pituitary hormones (like LH and FSH) are also crucial in regulating the ovarian cycle.

- Therefore, the Reason does not explain the Assertion correctly, as it overlooks the role of pituitary hormones in oogenesis and the menstrual cycle.