Menstrual Cycle

Question 1

What is puberty

Answer 1

Age at which the internal reproductive organs reach maturity usually between the ages of 12 and 14, onset of puberty is correlated with body mass

Question 2

What is the hormonal trigger of puberty

Answer 2

Hypothalamus releases luteinising hormone releasing hormone (LHRH), LHRH acts on the anterior pituitary gland causing it to release follicle stimulating hormone ( FSH) and luteinising hormone (LH). FSH and LH cause the ovaries to secrete oestrogens

Question 3

What is responsible for secondary sex characteristics

Answer 3

Oestrogen

Question 4

What are the secondary sex characteristics

Answer 4

Maturation of the uterus, uterine tubes and ovaries
Development and enlargement of the breasts
Growth of pubic and axillary hair
Increase in height
Widening of the pelvis
Increased far deposition in the subcutaneous tissue, especially at hips and breasts

Question 5

What is menarche

Answer 5

Onset of menstruation

Question 6

What is menopause

Answer 6

Ceasing of menstruation

Question 7

What is menstruation

Answer 7

A period of vaginal bleeding as the lining of the uterus sheds and is passed through the vagina

Question 8

What is the reproductive cycle

Answer 8

As series of events occurring regularly in females every 26-30 days through the childbearing period between menarche and menopause
The cycle consists of a series of changes taking place concurrently in the ovaries and uterine lining, stimulated by changes in hormones

Question 9

What happens in utero

Answer 9

By 20 weeks gestational age: primary ovary are formed in the developing ovaries if the fetus, over 1 million are present at time of birth, these follicles are immature

Question 10

What occurs during the reproductive cycle

Answer 10

During each cycle, one follicles mature, maturation is controlled by the hypothalamus secretes LHRH and the anterior pituitary gland which releases FSH and LH, which both act on the ovary

Question 11

What are the hormones from the ovary

Answer 11

During the first half of the cycle, while the ovum is developing within the follicle, it secretes increasing amounts of oestrogen
However, after ovulation, the corpus luteum secretes primarily progesterone with some oestrogen and inhibin

Question 12

What happens to the follicle before ovulation

Answer 12

The follicle develops from a immature follicle to a mature follicle, the follicle is filled with follicular fluid which increases, the Graafian follicle migrates from the cortex to the surface of the ovary

Question 13

What happens to follicle during ovulation

Answer 13

On day 14 of the cycle the follicle ruptures releasing the ovum into the peritoneal cavity, it’s ‘ caught’ by the fimbriae at the end of the uterine tube, it is propelled by cilia, along the uterine tube towards the uterus, body temp rises by 1 degree

Question 14

What happens to follicle after ovulation

Answer 14

Corpus luteum develops which secretes progesterone which causes LH and FSH to fall,
If the ovum is not fertilised falling LH levels lead to degeneration and death of the corpus luteum,
If the ovum is fertilised the corpus luteum continues to secrete hormones for 3-4 months

Question 15

What occurs in menstrual part of cycle

Answer 15

Days 1-4
Progesterone and oestrogen levels therefore fall, and the functional layer of the endometrium is shed in menstruation as the myometrium contracts

Question 16

What occurs in proliferative part of the cycle

Answer 16

Days 5-14
The maturing ovarian follicle stimulates the thickening of the functional layer of the endometrium in preparation for the reception for the fertilised ovum, the endometrium thickens becoming very vascular and rich in mucus- secreting glands, this stage ends at ovulation

Question 17

What occurs during secretory part of the cycle

Answer 17

Days 15-28
Progesterone from the corpus luteum stimulates the endometrium to become oedematous and the secretory glands produce increased amounts of watery mucus, this assists the motile spermatozoa through the uterus to the uterine tubes, where the ovum is usually fertilised, this stage begins at ovulation