(i) The head comprises of two parts acrosome and nucleus.
(ii) Acrosome is a small cap like poin structure present at the tip of the nuel and is formed mainly from the golgi of the spermatid.
(iii) It contains hyaluronidase, a protein enzyme, popularly known as sperm lysin which helps to penetrate the ovum  fertilization.
(iv) The nucleus is flat and oval.

Parturition is the completion of pregnancy and giving birth to the baby. The series of events that expels the infant from the uterus is collectively called "labour".

(i) human Chorionic Gonadotropin (hCG)
(ii) human Chorionic Somatomammotropin (hCS)
(iii) human Placental Lactogen (hPL)
(iv) Oestrogen and progesterone and relaxin.

(i) Sperm lysin is a proteolytic enzyme secreted in the acrosome of sperm.
(ii) It helps to penetrate the ovum during fertilization.
(iii) It is also called as hyaluronidase.

(i) The inner glandular layer of the uterus is called endometrium.
(ii) The endometrium undergoes cyclic changes during the menstrual cycle.

(i) The epididymis is a single highly coiled tube that temporarily stores the spermatozoa and they undergo physiological maturation and acquire increased motility and fertilizing capacity.
(ii) It is found in the testis.

(a) Sertoli cells or Nurse cells
(b) Spermatogonic cells or male germ cells.

Human Chorionic Gonadotropin (hCG), Human Chorionic Somatotropin (hCS) (or) Human Placental Lactogen (hPL), oestrogens and progesterone.

Spermiogenesis Spermatogenesis lt is a process of formation of sperms from immature germ cells It is a process of transformation of a non-motile spermatid into a motile
spermatozoan Number of cells increased as each spermatogonium produces four spermatids No change in number of cells as only one spermatid develops into a spermatozoa

(i) Change the napkins periodically for 4 to 6 hours.
(ii) Wash your genitals properly using clean lukewarm water.
(iii) Avoid using soaps and vaginal hygiene products.
(iv) Discard the sanitary napkins by incinerating.
(v) Wear clean and comfortable underwear. Avoid tight clothing.
(vi) Have healthy diet rich in Iron content and vitamins.

Lactation is the production of milk by mammary glands. The mammary glands show changes during every menstrual cycle, during pregnancy and lactation. Increased level of estrogens, progesterone and human Placental Lactogen (hPL) towards the end of pregnancy stimulate the hypothalamus towards prolactin - releasing factors. The anterior pituitary responds by secreting prolactin which plays a major role in lactogenesis.

The inner cell mass in the blastula is differentiated into epiblast and hypoblast immediately after implantation. The hypoblast is the embryonic endoderm and the epiblast is the ectoderm. The cells remaining in between the epiblast and the endoderm form the mesoderm. Thus the transformation of the blastocyst into a gastrula with the primary germ layers by the movement of the blastomeres is called gastrulation.

(i) The allantois is an extra embryonic membrane which forms a small out pocketing of embryonic tissue at the caudal end of the yolk sac.
(ii) It is the structural base for the umbilical cord that links the embryo to the placenta and ultimately it becomes part of the urinary bladder.

(i) During fertilization the acrosomal membrane of the sperm releases the proteolytic enzyme called hyaluronidase to break the hyaluronic acid which .binds the follicular cells around the ovum.
(ii) This is called acrosome reaction. This helps the sperm to enter the ovum.

(i) Menstrual flow occurs due to breakdown of endometrial lining of the uterus and its blood vessels due to decline in the level of progesterone and oestrogen.
(ii) This happens when the released ovum not fertilized.

(i) It is a temporary endocrine gland formed from the ruptured Graafian follicle.
(ii) It secretes a large amount of progesterone which is essential for maintenance of the endometrium of the uterus. If fertilization does not occur it degenerates.

(i) FSH stimulates testicular growth and enhances the production of Androgen Binding protein (ABP) by the sertoli cells and helps in the process of spermiogenesis.
(ii) LH acts on the Leydig cells and stimulates the synthesis of testosterone which in turn stimulates the process of spermatogenesis.

Human Ovum
a - Vitelline membrane
b - Nucleus
c - Zona Pellucida
d - Corona radiata

1. Testes are the primary male sex organs.
2. They are a pair of ovoid bodies lying in the scrotum.
3. The scrotum is a sac of skin that hangs outside the abdominal cavity.
4. Since viable sperms cannot be produced at normal body temperature, the scrotum is placed outside the abdominal cavity to provide a temperature 2-3°C lower than the normal internal body temperature.
5. Thus, the scrotum acts as a thermoregulator for spermatogenesis.

Colostrum is the yellowish fluid produced from the mother's mammary glands during initial few days of location, after parturition.
Significance:
1. It has less lactose than milk and almost no fat, but it contains more proteins, vitamin A and minerals.
2. Colostrum is also rich in IgA antibodies.
3. This helps to protect the infant's digestive tract against bacterial infection.
4. Breast milk is the ideal food for infants as it contains all the constituents in suitable concentration and is easily digestable.
5. It is fully sufficient till about 6 months of age and all infants must be breast fed by the mother to ensure the growth of a healthy baby.

	Germ Layers	Organ (or) Organ Systems
a.	Ectoderms	Central nervous system, peripheral nervous system, and mammary gland.
b.	Mesoderm	Cartilage and bones, muscles, urinogenital organs
c	Endoderm	Epithelium of respiratory tract, liver, thyroid gland.

The extra embryonic membranes include amnion, yolk sac, allantois, and chorion. They protect the embryo from desiccation, mechanical shock, absorption of nutrients, gaseous exchange and placental formation.

	Embryonic membrane	Function
a.	Amnion	Innermost two-layered membrane with amniotic fluid providing buoyancy to embryo from injury regulates temperature and acts as a medium for fetal movement.
b.	Chorion	Outermost layer covering and protecting the embryo.
c.	Allantois	Forms an outpocketing of embryonic tissue at the tail of yolk sac which forms umbilical cord that links embryo to placenta and finally becomes the part of urinary bladder
d.	Yolk sac	Forms a part of gut and acts a source of earliest blood cells and blood vessels

The mammary glands are modified sweat glands present in both sexes. It is rudimentary in the males and functional in the females. A pair of mammary glands is located in the thoracic region. It contains glandular tissue and variable quantities of fat with a median nipple surrounded by a pigmented area called the areola. Several sebaceous glands called the areolar glands are found on the surface and they reduce cracking of the skin of the nipple. Internally each mammary gland consists of 2-25 lobes, separated by fat and connective tissues. Each lobe is made up of lobules which contain acini or alveoli lined by epithelial cells. Cells of the alveoli secrete milk. The alveoli open into mammary tubules. The tubules of each lobe join to form a mammary duct. Several mammary ducts join to form wider mammary ampulla which is connected to the lactiferous duct in the nipple. Under the nipple, each lactiferous duct expands to form the lactiferous sinus which serves as a reservoir of milk. Each lactiferous duct opens separately by a minute pore on the surface of the nipple.
Normal development of the breast begins at puberty and progresses with changes during each menstrual cycle. In non-pregnant women, the glandular structure is largely underdeveloped and the breast size is largely due to amount of fat deposits. The size of the breast does not have an influence on the efficiency of lactation.

The extra embryonic membranes namely the amnion, yolk sac allantois and chorion protect the embryo from dessication, mechanical shock and help in the absorption of nutrients and exchange of gases.
Amnion
The amnion is a double layered translucent membrane filled with the amniotic fluid. It provides a buoyant environment to protect the developing embryo from injury, regulates the temperature of the foetus and provides a medium in which the foetus can move.
Yolk sac:
The yolk sac forms a part of the gut and is the source of the earliest blood cells and blood vessels.
Allantois:
The allantois is an extra embryonic membrane which forms a small out pocketing of embryonic tissue at the caudal end of the yolk sac. It is the structural base for the umbilical cord that links the embryo to the placenta and ultimately it becomes part of the urinary bladder.
Chorion:
The chorion is the outermost membrane which encloses the embryo and all other membranes and also helps in the formation of the placenta.
Chorionic Villi:
The trophoblast cells in the blastocyst send out several finger like projections called chorionic villi carrying foetal blood and are surrounded by sinuses that contain maternal blood. The chorionic villi and the uterine tissues form the disc-shaped placenta.
Placenta:
Placenta is a temporary endocrine organ formed during pregnancy and it connects the foetus to the uterine wall through the umbilical cord. It is the organ by which the nutritive, respiratory and excretory functions are fulfilled.

(i) Fertilisation occurs when a haploid sperm fuses with a haploid ovum to form a fertilized egg or diploid zygote.
(ii) The sperms deposited in the female reproductive tract undergo capacitation, which is a biochemical event that enables the sperm to penetrate and fertilise the egg.
(iii) Fertilization occurs only if the ovum and sperms are transported simultaneously to the ampullary isthmic junction of the fallopian tube.
(Iv) Before a sperm can enter the egg, it must penetrate the multiple layers of granulosa (follicular) cells which are around the ovum forming the corona radiata. The follicular cells are held together by an adhesive cementing substance called hyaluronic acid.
(v) The acrosomal membrane disintegrates releasing the proteolytic enzyme, hyaluronidase during sperm entry through the corona radiata and zona pellucida. This is called acrosomal reaction.
(vi) Once fertilisation is accomplished, cortical granules from the cytoplasm of the ovum form a barrier called the fertilisation membrane around the ovum preventing further penetration of other sperms. Thus polyspermy is prevented.
This is followed by cleavage

Spermatogenesis	Oogenesis
It takes place in the seminiferous tubules of testis	It occurs in the follicles of the ovary
It begins at puberty in males	In females it initiates in the foetal stages.
Spermatogonia are the sperm mother cells and many of them undergo maturation phase to form sperms.	Oogonia is the the egg mother cell and only one cell undergoes maturation phase at a time except in cases of fraternal twins.
I & II Mieotic divisions are equal and each spermatogonia forms 4 haploid spermatids.	I & II meiotic divisions are unequal and finally only one haploid ovum and 3 small haploid polar bodies are formed
The spermatids undergo a stage called Spermiogenesis to become functional sperm.	No such changes are observed.
The meiotic divisions are completed and spermaticly are formed.	The second meiotic division is never completed it fertilization does not take lace.