(i) A - Utreus B - Fallopian tube C - Ovary D - Vagina 
(ii) The penis reaches into the vaginal area thus, the sperms are released in vagina.

(i) g
(ii) a, e
(iii) d
(iv) b
(v) c, f

If implantation occurs, a portion of the endometrium of the uterus becomes modified and is called the decidua. The decidua is shed when the foetus is delivered. There are three kinds of decidua.
(i) Decidua basalis. It is the portion of the endometrium between the chorion and the myometrium of the uterus. The decidua basalis becomes the maternal part of the placenta.
(ii) Decidua capsularis. It is the portion of the endometrium between the embryo and uterine cavity.
(iii) Decidua parietalis. It is the portion of the modified endometrium that lines the entire pregnant uterus, except for the area where the placenta is forming.

The corpus luteum is formed in the mammalian ovary from a reputed Graaflan follicle after ovulation.It degenerates in the absence of fertilisation as the level of gonadotropins (FSH and LH) drops.

(i) 'a'  is zona pellucida.
The changes that occur in it when a sperm comes in contact with it, block the entry of other sperms.
(ii) Ampullary - isthmic junction of fallopian tube.

Cortisol and thyroxine.
These hormones are essential for supporting the foetal growth,metabolic changes in the mother and maintenance of pregnancy.

In males,gametogenesis is completed in the testes.
In females,it is completed in the ovary and fallopian tube.

• Trophoblast - helps in implantation / attachment to endometrium / attachment to uterus.
• Inner cell mass - gets differentiated into an embryo.

(a) FSH and LH levels - low
(b) Endometrium is highly vascularised, proliferative phase of uterine lining.
(c) Formation of corpus luteum, secretion of progesterone.

(i) Oogenesis
(ii) Clitoris
(iii) Mesometrium
(iv) Tubectomy
(v) Estrogens
(vi) Female rabbit

(a) Blastula stage of human embryo (also called blastocyst).
(b) 'a' in the figure is trophoblast (trophoectoderm). The trophoblast gives rise to extraembryonic membranes for the protection and nourishment of the embryo.
(c) The inner cell mass (after implantation in the uterus) gives rise to three germ layers (ectoderm, mesoderm and endoderm) or simply embryo.
(d) Inner cell mass (embryonal knob) represents the stem cells.

(a) I  - Teritiary follicle
II  - Ampullary-isthmic junction
III  - Ampullary-isthmic junction
IV  - Endometrium of uterus.
(b) The signals originate from the fully developed foetus and the placenta.
Pituitary releases oxytocin,that stimulates stronger contractions of the uterine muscles.

Duct System of male Reproductive System.
The intratesticular duct system starts with tubuli recti,which are the short,straight end segments of the seminiferous tubules ;these tubules connect the seminiferous tubules to the cuboidal epithelium-lined channels,called rete testis.
Form the rete testis arise 10-20 fine tubules,called vasa efferentia that leave the testis and open into the epididymis.
Epididymis is a single convoluted tubule that is located along the posterior surface of the testis.
The epididymis continues as the vas-deferens,that ascends into the abdominal cavity through inguinal canal.
It loops over the urinary bladder and receives a duct from the seminal vesicle of its side to form ejaculatory duct that runs through the prostate and opens into the prostatic urethra,just after its emergence from the urinary bladder.
The urethra receives the ducts of prostate gland and bulbourethral glands,a little ahead and runs through the penis to its openning called urethral meatus,to the outside.

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.

(i) It is not correct to blame a females for giving birth to female child. The sex of the baby is determined by the male gamete, because the man is heterogametic and produces two types of sperms x and y. Female is homogametic and produce only one type of ova i.e., X. Now if the X sperm with X chromosome fuses with egg the zygote XX will develop into female baby and if sperm with Y chromosome fuses with egg the (XY) baby would be male.
(ii) Values: Following values are not exhibited by Nisha's grandmother:
(a) understanding and awareness
(b) Respect to females.

(a) (A) Estrogen
(B) Progesterone
(b) (A) Maturing ovarian follicle/Graafian follicle
(B) Corpus luteum
(c) Formation of Graaffian follicle (releases estrogen) is followed by the formation of corpus luteum (releases progesterone)
(d) Role of A (Estrogen)-Leads to changes in the ovary and uterus/regeneration of endometrium through proliferation
Role of B (Progesterone)-Maintenance of endometrium for implantation of the fertilized ovum/maintenance of other events of pregnancy.
(e) In case of pregnancy.

(i) Tests are the primary sex organs in males. It is the site where male gametes or sperms are made.
(ii) The outermost covering of the tests is formed of a dense fibrous membrane called tunica albuginea.
(iii) Uterus has a thick wall composed of three layers of tissues as follows:
(a) Outer perimetrium
(b) Middle myometrium
(c) Inner endometrium
(iv) The teacher is patient, understanding, has scientific knowledge and is dutiful.

Fertilisation is the fusion of two gametic nuclei to form a diploid zygote.It involves a series of chemical and physical steps as follows:

The cortical cytoplasm of ovum shows the physicochemical reactions called the cortical reactions.

1.Sperm lysins dissolve the membranes around egg.centriole physically passes into ovum.

3.Normally these reactions result in the formation of fertilisation membrane outside the egg plasma membrane.

4.In man, cortical granules burst and release their contents between egg plasma membrane and zona pellucida i.e. perivitelline space (No fertilisation membrane formation).The plasma membrane shows increased permeability for water, phosphate and potassium.

5.Electrical potentiality of plasma membrane changes from positive to negative, NAD kinase enzyme becomes activated after fertilisation for the oxidation and reduction reaction of the cell.

6.Rate of DNA synthesis increases with great pace after fertilisation.Hence the ovum is now ready for mitosis(cleavage).

7.Cleavage results in multicellular in dividual.

(i) A-Spermatids, undergo spermiogenesis
(ii) A-Spermatids, B-Spermatogonium.
Spermatogonium (B) are diploid and have 46 chromosomes in humans, while spermatids (A) are haploid and have 23 chromosomes in case of human male.
(iii) E-spermatozoa, are motile cells
(iv) F-Sertoli cell, it provides nutrition to the germ cells
(v) Seminiferous tubule.