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Flashcards in Reproduction Deck (31)
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1

Testes

The male gonads, which produce spermatozoa.

2

Bulbourethral Gland

Secrete a clear mucus. It acts as a lubricant and much of it precedes the emission of the semen, with only a small amount in the semen.

3

Labia Majora

Cover and protects the inner structure of the vulva i.e. Collective name for the external genitalia.

4

Scrotum

Climate-control system for sperm production. Muscles of scrotum relax and contract to cool down the testis and warm up the testis respectively.

5

Seminiferous Tubules

Sperm cells mature from spermatogonia within the tubules due to the interstitial cells secreting testosterone.

6

Vas Deferens

Transports sperm from the epididymis to the urethra.

7

Urethra (in men)

This serves a dual function in males. It transports urine and semen to the exterior.

8

Semen

Created from the seminal vesicle, prostate gland, and bulbourethral gland. Aids with nourishment and development.

9

Seminal Vesicle

Secrete a thin fluid, rich in sugars and makes up 60% of the volume of semen.

10

Prostate Gland

Secretes a thin, milky, alkaline fluid.

11

Penis

The erectile tissue fills with blood during sexual arousal. This causes the penis to become erect. Transports sperm to the vagina.

12

Ovaries

Produce ova (eggs).

13

Uterine Tube

Funnel in which cilia and smooth muscle move egg to uterus.

14

Uterus

Protects and nourishes developing fetus.

15

Cervix

Connects uterus to the vagina/forms the birth canal with the uterus and vagina.

16

Vagina

Receives the penis during intercourse and with it, the sperm also.

17

Fimbriae

Passage of ovum from ovary to uterine tubes.

18

Labia Minora

Primarily protective of the inner structures of the vulva, also produces oily secretions for protections and lubrication.

19

Clitoris

Pleasure.

20

Urethra (in women)

Passageway for urine excretion.

21

Spermatogenesis

+ Seminiferous tubules lined with spermatogonia - divide by mitosis to make more.
+ Some spermatogonia move towards the centre of the tubule - become primary spermatocyte (at puberty).
+ Undergoes Meiosis I and produces two secondary spermatocytes.
+ Undergoes Meiosis II and produces 4 spermatids (haploid).
+ Then mature into spermatozoa (sperm).
+ Takes 72 days.

22

Oogenesis

+ Millions of oogonia (immature diploid cells) in ovaries from birth.
+ At birth they are in early Prophase I.
+ Surrounded by layer of follicular cells, referred to as a primary follicle.
+ At puberty, it completes Meiosis I - producing 2 cells. + - Secondary Oocytes (half DNA, nearly all cytoplasm).
+ - Polar Body (half DNA, nearly no cytoplasm).
+ Meiosis II begins - pauses at metaphase II (lining up at the middle, from pole to pole.)
+ It is expelled from the ovary in ovulation - the follicle ruptures.
+ Enters uterine tubes in ovulation - the follicle ruptures.
+ Enters uterine tube - if penetrated by sperm, it quickly completes meiosis II becomes ovum. Other becomes second polar body - that then disintegrates.

23

Hormones

Chemical messengers that are released by endocrine glands and travel throughout the blood.

24

Follicle-stimulating hormone (FSH)

+ Stimulates the development and maturation of the ovarian follicle in women. During development, the ovarian follicle releases its own hormone, oestrogen. FSH secretion is limited as the level of oestrogen increases in the blood.
+ FSH stimulates the epithelial tissue of the seminiferous tubules in the testes to produce sperm.

25

Luteinising hormone

+ Promotes the final maturation of the ovarian follicle, ovulation, and the formation of the corpus luteum. The corpus luteum, (a temporary endocrine structure involved in ovulation and early pregnancy), secretes another ovarian hormone, progesterone, as well as oestrogen. There is a gradual reduction in LH production as the level of progesterone in the blood increases.
+ LH stimulates cells in the testes to secrete testosterone.

26

Oestrogen

+ Secreted by the developing follicle in the ovary, and the corpus luteum in the follicle.
+ Placenta also secretes oestrogen.
+ Development of the reproductive system and secondary sexual characteristics. Important in the initial development of the lining of the uterus.

27

Progesterone

+ Produced by the corpus luteum.
+ Produced by the placenta.
+ Primary roles is to develop and maintain the lining of the uterus (called the endometrium), development and maintenance of the placenta, and development of milk-secreting glands in the breast.

28

Human Chorionic Gonadotropin (HCG)

+ Made by the placenta. Maintains the corpus luteum so it can keep making hormones.

29

Testosterone

+ Maintenance of reproductive organs, maturation of sperm, development of secondary sexual characteristics.

30

Ovarian Cycle

+ Includes the maturation of an egg and its release into a uterine tube, followed by the changes that occur immediately after in the ovary.
+ Roughly 28 day cycle.
+ Egg is released from one ovary at the mid-point of each cycle.
+ Maturation of the follicle and the formation of the corpus luteum are key stages in OC.
+ Oogenesis is occurring alongside the maturation of the follicle that surrounds each egg.
+ At ovulation, the egg is a secondary oocyte, paused at Metaphase II.
+ As the egg travels down the uterine tubes it remains paused at Metaphase II.
+ If fertilised, Meiosis II completes and a zygote is formed.
+ The ruptured follicle forms the Corpus Luteum.