(i) Testis
It produces the male gametes.
It secretes male hormone, testosterone.
(ii) Ovary
 It produces the female gametes, ovary.
It secretes female hormones, estrogen anncerd progesterone.

(i) Spermiogenesis is the process of transformation of spermatids into flagellated spermatozoa.
(ii) Spermiation is the process of release of spermatozoa from the seminiferous tubules.

Partiruition refers to the process of delivery if the fully-developed foetus,i.e.,childbirth.
Relaxin and oxytocin are the hormones involved in the process.

Six eggs

Six eggs

Menstrual cycle:
1. It is the reproductive cycle of female primates (such as monkeys, apes, and humans).
2. The menstrual cycle is the sequence of events that begins with one menstruation and ends with the next.
3. Menstruation occurs every 28/29 days in human females.
4. Menstruation, the follicular phase, ovulation, and the luteal phase are the four phases of the menstrual cycle.
The hormones involved in the process are:
(i) FSH, LH stimulate growth of follicle and maturation of ovum.
(ii) Oestrogen endometrial repair and growth.
(iii) Oestrogen and progesterone together prepare endometrium and other parts of the body for pregnancy.

Each testicular lobule contains 1-3 highly coiled seminiferous tubules. Each tubule is lined on its inside by two types of cells. The cuboidal cells are called male germ (spermatogenic) cells and few large pyramidal (supporting cells) are called Sertoli or nurse cells.
The former gives rise to sperms while the latter provide nutrition to the germ cells. 

Seminal fluid is a secretion of accessory sex glands of male that is, seminal vesicles, prostate gland and Cowper's glands. It is rich in fructose, calcium and certain enzymes.

1.lt helps it to survive and undergo meiosis II.
2.lt also helps in the nutrition of the zygote/embryo up to implantation.

46 chromosomes (23 pairs).

Oxytocin.

The menstrual phase (menstruation) is followed by follicular or proliferative phase;it is under the influence of follicle stimulating hormone (FSH) from the anterior pituitary. The primary follicle matures into Graafian follicle;the follicular cells secrete estrogens,which control the growth and maintenence of the secondary sex organs like uterus,fallopian tube,ect. The FSH and lutenising hormone reach their peak level around the 14th day of menstrual cycle. The peak level of LH or LH surge causes the rupture of Graafian follicle and release of ovum;this process is called ovulation. It is followed by luteal phase,where LH influences the ruptured Graafian follicle to transform into corpus luteum. Corpus luteum secretes large quantity of progesterone in the luteal phase,which is necessary for the growth and maintenance of endometrium of uterus for implantation. If fertilisation does not occur,corpus luteum degenerates and progesterone is not secreted. The endometrium degenerates and menstruation occurs.

Hormones controlling spermatogenesis.
Spermatogenesis is initiated by an increase in the secretion of GnRH (gonadotropin-releasing hormone) by the hypothalamus, at the age of puberty.
The increased levels of GnRH act on the anterior pituitary and stimulate it to secrete two gonaditropins namely:
(i) Follicle Stimulating Hormone (FSH) and
(ii) Luteinizing Hormone (LH).
LH acts o the Leydig cells and stimulates them to secrete testosterone.
FSH acts on Sertoli cells and stimulates them to secrete some factors which help in spermiogenesis.

The male accessory ducts are rete testis, vasa efferentia, epididymis and vas deferens.These ducts store and transport the sperms from the testes to the outside through the urethra. The male accessory glands are paired seminal vesicles, prostate gland and paired Bulbourethral glands. The secretion of these glands forms seminal plasma, which is rich in fructose, calcium and certain enzymes. The secretion of Bulbourethral glands lubricates the glans penis.

One
One
Two

T.S.of Ovary

In our society, Women are blamed for giving birth to daughters. This is wrong because sex of the baby is determined by the sperm that can have either X or Y-chromosomes.
Since Women have only one type of chromosome (X) in all the ova. 
If the sperm having X-chromosome fertilises the ovum (X), the resulting zygote (XX) will become a female. 
If the sperm having Y-chromosome fertilises the ovum (X), the resulting zygote (XY) will become a male.

The human male reproductive system consists of a scrotum, testes, testicular lobules, seminiferous tubules, urethra and penis.  The scrotum is a pouch of deeply pigmented skin divided into two separate sacs. Each sac contains one testis. Testes are the primary sex organs of the man. Each testicular lobules consists of 2-3 seminiferous tubules, blood vessels, nerves, and connective tissue. The male urethra is a common pathway for both semen and urine. The penis is the male copulatory organ and for conducting urine from the body.

Testes and ovaries are the primary sex organs in the males and females, respectively. Each testis bears large number of seminiferous tubules, which are the spermatogenic tissue of the testis. Similarly, ovaries bear the Graafian follicle or the ovarian follicles, which ultimately give rise to ovum. The testes secrete testosterone and the ovaries secrete oestrogen and progesterone

Spermatogenesis is the process of the production of sperms from the immature germ cells in males. It takes place in seminiferous tubules present inside the testes. During spermatogenesis, a diploid spermatogonium (male germ cell) increases its size to form a diploid primary spermatocyte. This diploid primary spermatocyte undergoes first meiotic division (meiosis I), which is a reductional division to form two equal haploid secondary spermatocytes. Each secondary spermatocyte then undergoes second meiotic division (meiosis II) to form two equal haploid spermatids. Hence, a diploid spermatogonium produces four haploid spermatids. These spermatids are transformed into spermatozoa (sperm) by the process called spermiogenesis.

Graafian follicle is a fluid-filled structure in the mammalian ovary which carries ovum development.

(a) Corpus luteum 
It secretes large amounts of progesterone, which is essential for maintenance of the endometrium, implantation of embryo and other events of pregnancy.
(b) Endometrium
 It is the inner most glandular lining of the wall of the uterus. - It undergoes cyclical changes during menstrual cycle and prepares itself for the implantation of embryo.
(c) Acrosome
The acrosome contains enzymes which help in dissolving the envelopes (zona pellucida and plasma membrane) of the ovum and facilitate the entry of sperm into the cytoplasm of the ovum.
(d) Sperm tail
It facilitates the movement of sperm inside the female reproductive tract to reach the ovum for fertilisation.
(e) Fimbriae
They help in collection of the ovum after ovulation, into the fallopian tube.

(a) A. Seminal vesicle
B. Prostate gland
C. Bulbourethral gland
(i) Their secretions constitute seminal plasma.
(b) Testis is the primary sex organ and it is located in the scrotum.

A. Acrosome
(i) The secretions.enzymes of acrosome dissolve the egg envelopes and help the sperm enter the cytoplasm of the ovum.
B. Mitochondria
(i) The mitochondria in the middle piece provide energy for the sperm motility in the female reproductive tract towards ovum.
C. Tail
(i) It facilitates the movement of sperm towards the ovum for fertilisation.

(a) 1. Gonadotropin-releasing hormone (GnRH)
2. Follicle-stimulating hormone (FSH) Luteinising hormone (LH)
3. Testosterone
(b) (i)  Leydig cells secrete testosterone.
(ii) Sertoli cells secrete some factors necessary for spermiogenesis.

(i) 75 million
(b) 300 million
c) (i) 92 chromatids
(ii) 46 chromatids

(A) (i) - (d), (ii) - (b), (iii) - (c), (iv) - (e)
(b) (i) - Luteinising hormone
(ii) - Progesterone

(a) (i) It is called proliferative phase because the endometrium of the uterus is regenerated through prol iferation of its cells.
(ii) It is called follicular phase as the primary  follicle in the ovary grows to become a fully mature Graafian follicle under the influence of follicle-stimulating hormone.
(b) (i) Corpus luteum is formed from the remaining parts of the ruptured Graafian follicle.
(ii) Corpus luteum secretes large amounts of progesterone.

(a) X is hormone estrogen.
(i) It is secreted by the cells of the developing follicle.
Y is hormone progesterone.
(ii) It is secreted by corpus luteum.
(b) (i) X is secreted by the cells of the follicle during follicular phase before ovulation; after the rupture of Graafian follicle, there is no secretion of estrogen.
(ii) Y is secreted by corpus luteum that is formed after ovulation in the luteal phase; hence X peaks before Y.

(a) X is luteinizing hormone (LH).
Y is follicle-stimulating hormone (FSH).
(b) Functions of X
(i) The LH-surge causes rupture of Graafian follicle and release of ovum, in the process, called ovulation.
(ii) It influences the formation of corpus luteum from the remaining parts of the Graafian follicle and secretion of progesterone from it.
Functions of Y
 (i) It stimulates the growth of a primary follicleinto a Graafian follicle and thus, influences oogenesis.
(ii) It stimulates the cells of the developing follicle to secrete estrogens.

(i) 1. Gonadotropin-releasing hormone (GnRH)
2. Follicle-stimulating hormone (FSH) and Luteinising hormone (LH)
3. Progesterone.
(b) Corpus luteum secretes progesterone.

(a) A is a morula
B is a blastocyst.
 

(a) It is a blastocyst.
(b) 'a' is inner cell mass.
'b' is trophoblast.
(c) Stem cells are present in the inner cell mass.
(d) Role of Trophoblast.
(i) It becomes attached to the endometrium for implantation.
(ii) The chorionic villi appearing on it form the foetal part of placenta.

(b) They induce mild uterine contractions, called foetal ejection reflex.
(c) This triggers the release of oxytocin from the maternal pituitary.
(e) The stimulatory reflex between the uterine contractions and oxytocin secretion continues and results in stronger and stronger uterine contractions.
(f) This leads to expulsion of the foetus through the birth canal, i.e., parturition.
 

(i) (b) : P is an epididymis that stores the sperms and secretes a fluid which is considered to nourish the sperms
(ii) (b) : Q - Vas deferens, R - Ejaculatory duct S - Bulbourethral gland, T - Seminal vesicle
(iii) (c) :Q (vas deferens) arises from cauda epididymis
(iv) (d)
(v) (a)

(i) (c) : FSH stimulates the growth of Graafian follicles, development of egg oocyte within the follicles to complete the meiosis I to form secondary oocyte. It also stimulates the formation of estrogen.
(ii) (d) : LH induces rupture of mature Graafian follicle and thereby the release of secondary oocyte.
(iii) (c) : FSH stimulates the growth of Graafian follicles, development of egg oocyte within the follicles to complete the meiosis I to form secondary oocyte. It also stimulates the formation of estrogen.
(iv) (a)
(v) (d) : The rising level of progesterone inhibits the release of GnRH, which in turn inhibits production of FSH, LH and progesterone.

(i) (d): During menstrual phase, the endometrium breaks down and menstruation begins.
(ii) (c) : Proliferative phase extends for about 10-12 days usually from day 6th to 13th in a 28 day cycle
(iii) (a)
(iv) (d) : During ovulatory phase, both LH and FSH attain a peak level
(v) (b)

(i) (a)
(ii) (d) : T is mammary ampulla and R is mammary alveoli.
(iii) (b) : Near the nipple, mammary ducts expand to form mammary ampullae where some milk may be stored before going to lactiferous ducts.
(iv) (c)
(v) (c) : The fibrous (connective) tissue supports the alveoli and the ducts.

(i) (a): In multiplication phase, the undifferentiated primordial germ cells divide several times by mitosis to produce large number of spermatogonia
(ii) (c)
(iii) (b) : Transformation of spermatids (L) into spermatozoa (M) is known as spermiogenesis or spermateliosis
(iv) (c)
(v) (d) : FSH acts on spermatogonia to stimulate sperm production

(i) (c)
(ii) (b)
(iii) (a) : Relaxin increases the flexibility of the pubis symphysis and ligaments of sacroiliac and sacrococcygeal joints and helps to dilate the uterine cervix during labour pains.
(iv) (a) : hPL, hCG and relaxin are produced in women only during pregnancy.
(v) (b)

(i) (c) : The secretions of female genital tract remove coating substances deposited on the surface of the sperms. This phenomenon of sperm activation is called capacitation
(ii) (d)
(iii) (b) : Binding of sperm to the secondary oocyte induces depolarisation of the oocyte plasma membrane. Depolarisation prevents polyspermy and ensures monospermy
(iv) (c) : Fertilisation restores diploid number of chromosomes. It introduces variations as it combines characters of the two parents.
(v) (b)

(i) (d)
(ii) (a) : In humans, ovum is released from the ovary as secondary oocyte
(iii) (c)
(iv) (b) : V - Cortical granules
W - Cells of corona radiata
X - Zona pellucid a
Y - Perivitelline space
Z - Plasma membrane
(v) (d) : Ovum has large amount of cytoplasm called ooplasm

(i) (b)
(ii) (c) : J - Spermatogonium,
K - Sertoli (sustentacular) cell,
L - Primary spermatocyte,
M- Secondary spermatocyte
N - Spermatid,
O- Spermatozoa
(iii) (a): Spermatogonium and primary spermatocytes are diploid (2N), i.e., 46 chromosomes
(iv) (b)
(v) (d) : Spermatogenesis starts at puberty due to significant increase in the secretion of GnRH.

(i) (a) : Embryo with 8-16 blastomeres is solid mass of cells, known as morula.
(ii) (c) : Embryo with 64 cells is called blastula (blastocyst) and has blastocyst cavity. Blastocyst is composed of an outer envelope of cells called trophoblast and inner cell mass.
(iii) (a) : Implantation is the attachment of blastocyst to the uterine wall. The portion of blastocyst where the inner cell mass is located lies against the endometrium of uterus.
(iv) (d)
(v) (b)