Female And Male Reproductive System LO

Question 1

Describe the anatomy of the external female reproductive system

Answer 1

Mons pubis - rounded pad of fat
Labia majora - 2 folds of fat and areolar tissue
Labia minora - 2 small subcutaneous folds
Prepuce - retractable piece of skin, formed by labia minora
Clitoris - external = filled with nerve endings, internal = vascular, erectile tissue
Fourchette
Urethra - in front of vagina, urine exits body
Vagina - partially closed by hymen
Vestibular gland - secrete mucus to keep vulva moist
Perineum - gives attachment to muscles of pelvic floor

Question 2

Describe the anatomy of the internal female reproductive system

Answer 2

Uterus - posterior to bladder, anterior to rectum
Endometrium - thickens and is shed during menstruation
Myometrium - mass of smooth muscles fibres interlaced with areolar tissue
Fallopian tube - lead ovum from ovary to uterus
Fimbriae - attached to ovary
Ovary - produces oocytes
Ovarian ligament
Vagina - runs up between bladder and rectum. PH 3.5-4.9

Question 3

Describe development of secondary sex characteristics in females

Answer 3

Usually occurs between the ages of 10-14
- rise in production of reproductive hormones
- onset of menstruation
- ovarian activity controlled by FSH and LH from anterior pituitary
1) maturation of uterus, Fallopian tubes, ovary
2) increased secretion of vestibular glands
3) enlargement of breasts
4) growth of pubic and auxiliary hair
5) increase in height, widening of pelvis
6) increased fat deposition in hips

Question 4

What is menarche?

Answer 4

Menarche defines the onset of menstruation

Question 5

Describe what is happening in the ovary during the menstrual cycle

Answer 5

Before ovulation - follicle develops from primordial follicle to a mature graafin follicle. This follicle migrates from cortex to surface of ovary.
(Ovulation) day 14 - follicle ruptures, releasing ovum into peritoneal cavity. Caught by fimbriae and propelled by cilia along uterine tube towards uterus. Body temp increases 1 degree
After ovulation - corpus luteum develops and secretes progesterone + oestrogen inhibin. FSH and LH levels fall. If ovum not fertilised falling LH levels lead to degeneration of corpus luteum

Question 6

Describe what is happening to the uterus during the menstrual cycle

Answer 6

Days 1-4 - progesterone and oestrogen levels fall and functional layer of endometrium is shed as myometrium contracts
Days 5-14 - maturing ovarian follicle stimulates thickening of endometrium in preparation for receiving fertilised ovum. Endometrium becomes vascular + rich in mucus secreting glands. Ends at ovulation
Days 15-28 - progesterone from corpus luteum stimulates endometrium to become oedematous and excretory glands produce more mucus. Assists spermatozoa to reach ovum. Begins at ovulation

Question 7

Discuss the process of spermatogenesis and spermiogenesis

Answer 7

1) primordial sperm cell differentiates into spermatogonium
2) this then forms a spermatocyte via mitosis
3) spermatocytes then form secondary spermatocytes during meiosis I due to DNA replication and crossing over of gametes
4) these are then turned into spermatocytes cells in meiosis II and each cells get 1 of each chromatid.
5) finally, turned into spermatozoa in spermiogenesis

Question 8

Describe the process of fertilisation and implantation

Answer 8

1) sperm deposition
2) capacitation - the change sperm undergo in the female reproductive tract that enables them to penetrate and fertilise an ovum
3) penetration of corona radiata - granules in cells, occurs by across me reaction
4) penetration of zona pellucida - glycoprotein layer between corona radiata and oocyte membrane
5) fusion of the sperm cell membrane with the oocyte cell membrane
Oocyte completes meiosis II - becomes ovum
Gamete fusion - becomes zygote

Question 9

Describe the development of secondary sexual characteristics at puberty in the male

Answer 9

• Occurs between the ages of 10-14
• LH from anterior pituitary increase production of testosterone
  1) growth of muscle and bone
  2) increase in height and weight
  3) enlargement of larynx
  4) growth of hair on face, axillae, chest, abdomen, pubis
  5) enlargement of penis and prostate
  6) production of spermatozoa
  7) thickening of skin

Question 10

Describe the changes in the breast during puberty, menstrual cycle and pregnancy

Answer 10

Puberty (sexually dimorphism breast development)
- under influence of sex hormones, particularly oestrogen and progesterone
- usually first secondary sex characteristic, preceding pubic hair by 6 months
- ductal development and branching, lobular development occurs
- nipple size increases, primary areolar becomes pigmented
- cyclical changes occur
Menstruation
- may be swollen due to increased blood flow
Pregnancy
- glandular development under influence of progesterone
- ductal development under influence of oestrogen
- colostrum is synthesised, but lactation is suppressed under influence of placental hormones

Question 11

Describe the structure and function of a spermatozoon

Answer 11

Structure
- head
- body
- tail
Function
- to be released during sexual intercourse and to eventually meet with an ovum