Describe the role of hormones in the mammalian female reproductive cycle. (20 marks)

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Follicle stimulating hormone (FHS); is secreted from the anterior lobe of the pituitary gland just after menstruation;  It causes Graafian follicle to grow in the ovary;

FSH also stimulates tissues
of the ovary to produce oestrogen;

Oestrogen; brings about healing and repair of endometrium; destroyed during menstruation;

Accumulation of oestrogen; stimulates pituitary gland produce Luteinising hormone (LH);

Luteinising hormone (LH); stimulates maturation of graafian follicle;

The mature graafian follicle releases an ovum into funnel shaped part of the ovary;  This is known as ovulation;

LH also brings about changing of graafian follicle into corpus luteum;

LH then stimulates
corpus luteum to secrete progesterone;

Progesterone; stimulates thickening of the endometrium and increases blood supply to the endometrium; in preparation for implantation.

When fertilization has taken place, progesterone
levels increase and this inhibits secretion of FSH; hence no more growth of graafian follicle during pregnancy;
TOTAL 22 MAX 20

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