Explain various mechanical methods of birth control.

The mechanical methods of birth control are described below: Condoms: A rubber or latex sheath is put on the male genital organ before sexual intercourse to prevent the fertilization of the ovum and sperm. Diaphragms: The female condoms that cover the vagina or cervix are known as diaphragms. This method also prevents fusion or fertilization. Copper-T: It is an intrauterine device that releases copper ions, which declines sperm motility, therefore preventing the fertilization of the gametes.

Draw a neat labelled diagram of T.S. of the ovary and describe various phases of the menstrual cycle.

Figure: T.S of Human Ovary The menstrual cycle is a reproductive cycle that takes place in the females of the group of primates. The menstrual cycle is divided into four phases: Menstrual phase: It extends from the 1st to the 4th day of the cycle. It occurs in the absence of fertilisation. During this phase, bleeding occurs as the endometrium of the uterus is sloughed off. The menstrual flow consists of secretion of endometrial glands, cell debris, unfertilized ovum. After the 4th day, once again the FSH secretion from the pituitary is resumed and the new follicle starts developing. Follicular phase: When the ovary is in this phase, the uterus enters the proliferative phase. This takes place from the 5th to the 13th day of the cycle. During this phase new primordial follicle in the ovary develops due to the action of FSH from the pituitary. It gradually changes into the Graafian follicle and the production of estrogen starts. Only one follicle develops in one cycle. Corresponding to the changes in the ovary, the uterus also undergoes proliferation. Endometrial glands, stimulated by estrogen repair the uterus. Ovulatory phase: During this phase, ovulation takes place. It usually occurs on the 14th day. Mature Graafian follicle ruptures due to LH secretion by the pituitary. Graafian follicle bursts and releases the ovum. This ovum along with the follicular fluid is picked up by the fimbriae of the infundibulum of the fallopian tube. It passes through the fallopian tube, where, if it happens to meet a sperm, it is fertilised. If not fertilised, the ovum degenerates. Luteal phase: It corresponds with the secretory phase in the uterus. It takes place between the 15th to 28th days of the cycle.

Match the pairs and rewrite: Column I Column II (1) Mechanical Means (a) Saheli (2) Physiological device (b) Jellies (3) Chemical device (c) Vasectomy (4) Permanent method (d) Diaphragm

Given in the table are variou s birth control methods that function by different means. The correct match has been given below: Column I Column II (1) Mechanical Means (d) Diaphragm (2) Physiological device (a) Saheli (3) Chemical device (b) Jellies (4) Permanent method (c) Vasectomy