19 - Reproductive system Flashcards Preview

X MFEL1010 - Innføring i medisin for ikke-medsinere > 19 - Reproductive system > Flashcards

Flashcards in 19 - Reproductive system Deck (56):
1

List the four functions of the reproductive system.

1. Production of gametes.
2. Fertilisation
3. Development and nourishment of a new individual
4. Production of reproductive hormones.

2

Explain the following function of the reproductive system: 1. Production of gametes.

The reproductive system produces gametes: sperm cells in the testes of males and oocytes (eggs) in the ovaries of females.

3

Explain the following function of the reproductive system: 2. Fertilisation

The reproductive system enhances fertilisation of the oocyte by the sperm. The duct system in males nourishes sperm until they are mature and are deposited in the female reproductive tract by the penis. The female reproductive system receives the male's sperm and transports them to the fertilisation site.

4

Explain the following function of the reproductive system: 3. Development and nourishment of a new individual

The female reproductive system nurtures the development of a new individual in the uterus until birth and provides nourishment (milk) after birth.

5

Explain the following function of the reproductive system: 4. Production of reproductive hormones.

Hormones produced by the reproductive system control its development and the development of gender-specific body form. These hormones are also essential for the normal function of the reproductive system and for reproductive behaviour.

6

What are gametes?

Sex cells! (sex sells)

7

The formation of gametes in males and females occur by a type of cell division called...

meiosis.

8

Where does meiosis occur?

In the testis and ovary.

9

During meiosis, x cell(s) undergoes y consecutive cell division(s) to produce z daughter cells, each having n chromosomes.

During meiosis, one cell undergoes two consecutive cell divisions to produce four daughter cells, each having half as many chromosomes as the parent cell.

10

Sperm cells are developed in the ..

seminiferous tubules in the testes.

11

What are the major reproductive hormones in males?

1. Gonadotropin-releasing hormone (GnRH)
2. Lutenizing hormone (LH)
3. Follicle-stimulating hormone (FSH)
4. Testosterone
5. Inhibit

12

What are the major reproductive hormones in females?

1. Gonadotropin-releasing hormone (GnRH)
2. Lutenizing hormone (LH)
3. Follicle-stimulating hormone (FSH)
4. Oestrogen
5. Progesterone
6. Oxytocin

13

What is the source and target tissue of the Gonadotropin-releasing hormone (GnRH) in males?

Hypothalamus
Anterior pituitary

14

What is the source and target tissue of Lutenizing hormone (LH) in males?

Anterior pituitary
Interstitial cells of the testes

15

What is the source and target tissue of Follicle-stimulating hormone (FSH) in males?

Anterior pituitary
Seminiferous tubules

16

What is the source and target tissue of Testosterone in males?

Interstitial cells of testes

Testes; body tissues
Anterior pituitary and hypothalamus

17

What is the source and target tissue of Inhibit in males?

Sustentacular cells
Anterior pituitary

18

What is the source and target tissue of Gonadotropin-releasing hormone in females?

Hypothalamus
Anterior pituitary

19

What is the source and target tissue of Lutenizing hormone (LH) in females?

Anterior pituitary
Ovaries

20

What is the source and target tissue of Follicle-stimulating hormone in females?

Anterior pituitary
Ovaries

21

What is the source and target tissue of Oestrogen in females?

Follicles of ovaries and corpus luteum

Uterus
Breasts
Anterior pituitary and hypothalamus
Other tissues

22

What is the source and target tissue of Progesterone in females?

Corpus lute of ovaries

Uterus
Breasts
Anterior pituitary
Other tissues

23

What is the source and target tissue of Oxytocin in females?

Posterior pituitary

Uterus and mammary glands

24

What is the source and target tissue of Human chorionic gonadotropin in females?

Placenta

Corpus luteum of ovaries.

25

What is the response of the anterior pituitary in males to Gonadotropin-releasing hormone?

Stimulates secretion of LH and FSH.

26

What is the response of the Interstitial cells of the testes to Lutenizing hormone (LH) ?

Stimulates synthesis and secretion of testosterone.

27

What is the response of the Seminiferous tubules of males to Follicle-stimulating hormone?

Supports spermatogenesis and inhibin secretion.

28

What is the response of the Testes and body tissues to testosterone?

Development and maintenance of reproductive organs; supports spermatogenesis and causes the development and maintenance of secondary sexual characteristics.

29

What is the response of the anterior pituitary and hypothalamus to testosterone?

Inhibits GnRH, lH and FSH secretion through negative feedback.

30

What is the response of the anterior pituitary to Inhibin?

Inhibits FSH secretion through negative feedback.

31

What is the response of the anterior pituitary to Gonadotropin-releasing hormone (GnRH) in females?

Stimulates secretion of LH and FSH

32

What is the response of the Ovaries to Lutenizing Hormone (LH)?

Causes follicles to complete maturation and undergo ovulation; causes ovulation; causes the ovulated follicle to become the corpus luteum.

33

What is the response of the ovaries to Follicle-stimulating hormone? (FSH)

Causes follicles to begin development

34

What is the response of the uterus to oestrogen?

Proliferation of endometrial cells.

35

What is the response of the breasts to oestrogen?

Development of mammary glands (especially duct systems).

36

What is the response of the anterior pituitary and hypothalamus to oestrogen?

Positive feedback before ovulation, resulting in increased LH and FSH secretion; negative feedback with progesterone on the hypothalamus and anterior pituitary after ovulation, resulting in deceased LH and FSH secretion.

37

What is the response of other body tissues to oestrogen?

Development and maintenance of secondary sexual characteristics.

38

What is the response of the uterus to progesterone?

Enlargement of endometrial cells and secretion of fluid from uterine glands; maintenance of pregnant state.

39

What is the response of the breasts to progesterone?

Development of mammary glands (especially alveoli).

40

What is the response of the anterior pituitary to progesterone?

Negative feedback, with oestrogen, on the hypothalamus and anterior pituitary after ovulation, resulting in decreased LH and FSH secretion.

41

What is the response of the other tissues to progesterone?

Secondary sexual characteristics.

42

What is the response of the uterus and mammary glands to oxytocin?

Contraction of uterine smooth muscle and contraction of cells in the breasts, resulting in milk letdown in lactating women.

43

What is the response of the corpus luteum of ovaries to Human chorionic gonadotropin?

Maintains corpus luteum and increases its rate of progesterone secretion during first one-third of pregnancy; increases testosterone production in testes of male foetuses.

44

Testosterone has an inhibiting effect on the release of GnRH, LH and FSH. Yet the levels of all three rises with testosterone levels during puberty in males, why?

Beginning just before puberty and continuing throughout puberty, developmental changes in the hypothalamus case the hypothalamus and the anterior pituitary gland to become much less sensitive to the inhibitory effect of testosterone, and the rate of GnRH, LH and FSH secretion increases. This same mechanism exist in females, but Oestrogen and progesterone are the inhibitors.

45

The female reproductive organs consist of ...

1. The ovaries
2. The uterine tubes
3. The uterus
4. The vagina
5. The external genitalia
6. The mammary glands

46

Define ovulation.

Ovulation is the release of an oocyte from an ovary.

47

What is the corpus luteum?

After ovulation, the remaining cells of the ruptured follicle are transformed into a glandular structure called the corpus luteum. If pregnancy occurs, the corpus luteum enlarges in response to a hormone secreted by the placenta called human chorionic gonadotropin hormone.

48

Define menses.

Menses is a period of mild haemorrhage during which part of the endometrium is sloughed and expelled from the uterus.

49

Typically, the menstrual cycle is about x days long.

28

50

What is considered the first day of the menstrual cycle?

The first day of menstrual bleeding.

51

Menses typically last ...

4 or 5 days.

52

Ovulation occurs on day x of the menstrual cycle.

14

53

What is the proliferative phase and when is it?

Between the end of menses and ovulation is the proliferative phase, which refers to proliferation of the endometrium.

54

What happens in the ovaries in the proliferative phase?

During the proliferative phase, the secondary follicles in the ovary mature; as they do so, they secrete increasing amounts of oestrogen.

55

Ovulation occurs in response to large increases in LH levels that normally occurs on the 14th day of the menstrual cycle. What brought about this increase?

The sustained increase of oestrogen secreted by the developing follicles stimulates GnRH secretion from the hypothalamus. GnRH in rerun, triggers FSH and LH secretion from the anterior pituitary gland. FSH stimulates oestrogen secretion at an increasing rate from the developing follicles. This positive-feedback loop produces a series of larger and larger surges of FSH and LH secretion.

56

What and when is the secretory phase?

Between ovulation and the next menses is the secretory phase of the menstrual cycle, called this because of the small amount of fluid secreted by the cells of the endometrium. During the secretory phase, the lining of the uterus reaches its greatest degree of development.