Puberty

Question 1

Define puberty

Answer 1

• stage of human growth and development
• sexually mature, capable of reproduction
• sex organs mature, secrete sex hormones (testosterone, progesterone, oestrogen)
• secondary sexual characteristics developed

Question 2

Secondary sexual characteristics (Male)

Answer 2

• hair appear in pubic regions, armpits, face
• penis and testicles increase in size
• larnyx enlarges, voice deepens
• production of sperms begin

Question 3

Secondary sexual characteristics (Female)

Answer 3

• hair appear in pubic regions, armpits
• breast and uterus enlarge
• hips broaden
• menstruation and ovulation begin

Question 4

Menstrual cycle

Answer 4

• cycle of events taking plc in female reproductive system every month
• menstruation: monthly discharge of blood/menses frm uterus via vagina
• 28 days (average)
• natural variation range from 21 to 33 days
• can be affected by stress, illness, unbalanced diet/malnutrition

Question 5

Menopause

Answer 5

• condition where female ovaries eventually stop producing ova and sex hormones
• menstrual cycle stops

Question 6

Primary follicles

Answer 6

• young and developing follicles in ovary
• each consists of potential egg cell
• surrounded by layer of follicle cells

Question 7

Graafian follicle

Answer 7

• primary follicle may develop into Graafian follicle
• contains mature egg surrounded by follicle cells and fluid filled space
• ready to be released into oviduct
• one ovum released every month, ovaries take turns (generally)

Question 8

Follicle (ovulation)

Answer 8

• 14th day

- occurs when Graafian follicle ruptures, release ovum into oviduct funnel

Question 9

Follicle (aft ovulation)

Answer 9

• Graafian follicle develops into corpus luteum
• corpus luteum produces hormones, prepare body for pregnancy
• if no fertilization occurs, corpus luteum eventually breaks down

Question 10

Stages in menstrual cycle

Answer 10

1. Menstrual flow stage (Day 1-5)
2. Follicle stage (Day 6-13)
3. Ovulation (Day 14)
4. Corpus Luteum stage (Day 15-28)

Question 11

Menstrual flow stage (Day 1-5)

Answer 11

• uterine lining breaks down
• flows frm uterus to vagina
• anterior pituitary gland secretes follicle-stimulating hormone (FSH) into bloodstream

Question 12

Follicle stage (Day 6-13) [Oestrogen]

Answer 12

• FSH stimulates follicle development in ovaries, oestrogen secretions by follicles
• oestrogen: causes repair and growth of uterine lining, making it thick and spongy with blood vessels
• high conc oestrogen inhibits FSH production (prevent growth of more follicles)
• high conc oestrogen stimulates pituitary gland to secrete luteinising hormone (LH)

Question 13

Ovulation (Day 14)

Answer 13

• lutenising hormone causes
  1. ovulation
  2. formation of corpus luteum
• corpus luteum secretes progesterone, some oestrogen

Question 14

Corpus Luteum stage (Day 15-28) [Progesterone]

Answer 14

• Progesterone prepares uterine lining for the fertilised egg by:
  1. causing it to thicken further
  2. supplying it with blood capillaries
• inhibits:
  1. ovulation (don’t need anymore development of follicles)
  2. FSH production

Question 15

Follicle stage (Day 6-13)

Answer 15

• FSH stimulates follicle development in ovaries, oestrogen secretions by follicles
• oestrogen: causes repair and growth of uterine lining, making it thick and spongy with blood vessels
• high conc oestrogen inhibits FSH production (prevent growth of more follicles)
• high conc oestrogen stimulates pituitary gland to secrete luteinising hormone (LH)

Question 16

What happens when fertilisation occurs?

Answer 16

• fertilised egg becomes zygote, then develops into embryo
• embryo embeds itself into uterine lining
• secrete hormone that prevents corpus luteum from breaking down until placenta is formed
• corpus luteum continues to secrete oestrogen and progesterone until placenta forms (can take over job)

Question 17

Corpus Luteum stage (Day 15-28)

Answer 17

• progesterone prepares uterine lining for fertilised egg by:
  1. cause it to further thicken
  2. supplying it with blood capillaries
• progesterone inhibits:
  1. ovulation
  2. FSH production

Question 18

What happens when no fertilisation occurs? (menstruation)

Answer 18

• egg breaks down
• high lvl of progesterone inhibits LH production
• lowered LH lvls cause corpus luteum to break down
• progesterone is no longer secreted
• uterine lining breaks down, discharged tgt with blood thru vagina (beginning of menstruation)
• FSH is produced by anterior pituitary gland, menstrual cycle repeated

Question 19

Fertile and infertile period

Answer 19

• ovulation occurs on day 14
• egg can be fertilised up to 48 hrs aft released frm ovary
• sperms can live for 2-3 days in female reproductive system
• sexual intercourse between days 11-16, high chance (fertile period)
• rest of days is infertile period