Reproductive system Flashcards
(93 cards)
1
Q
Where is sperm produced and where is it stored?
A
Produced in the lining of the seminiferous tubules, stored in the epididymus
2
Q
What are the 3 roles of progesterone in women?
A
- Regulate development of the endometrium
- Prepare suitable environment for embryo nourishment
- Allow the breasts to produce milk
3
Q
Name and describe the 3 layers of the uterine wall
A
- Para/perimetrium - visceral peritoneum
- Myometrium - interwoven smooth muscle
- Endometrium - the epithelial layer
4
Q
Name the 4 parts of the uterine tube
A
- Infundibulum
- Ampulla
- Isthmus
- Intramural
5
Q
What is the corpus luteum?
A
The yellow body, a temporary structure made by the follicle after ovulation, after the egg leaves. It produced progesterone and some oestrogen.
6
Q
What is the corpus albicans?
A
The white body, the corpus luteum forms the corpus albicans if fertilisation does not occur.
The cells are replaced by collagen scarring
7
Q
Name and describe the 3 kinds of fertilisation
A
- Oviparous - egg laid outside the female body
- Ovoviviparous - eggs are produced and hatched within the body of the parent
- Viviparous - development within the female followed by a live birth
8
Q
What is gametogenesis?
A
The production of haploid gametes (eggs or sperm).
9
Q
What determines gonadal sex in mammals and birds?
A
Chromosomes: XY/ZZ → Testes, XX/ZW → Ovaries.
10
Q
How does sex determination occur in reptiles?
A
Temperature-dependent: 16–28°C → Testes; >32°C → Ovaries.
11
Q
What hormone masculinises genitalia in mammals?
A
Androgens.
12
Q
What hormone feminises genitalia in birds?
A
Oestrogen.
13
Q
Where are female internal reproductive organs located?
A
In the pelvic cavity, superiorly covered by peritoneum.
14
Q
What are the functions of the ovaries?
A
Oogenesis, hormone production (oestrogen and progesterone), and follicle maturation.
15
Q
What is the first stage of follicular development?
A
Primordial follicle: primary oocyte + single layer of flattened granulosa cells.
16
Q
What is the second stage of follicle development? What happens here?
A
- Primordial follicle –> Primary follicle
- Granulosa cells change from being flat squamous to bigger cuboidl cells, and they become stratified
17
Q
What is the zona pellucida?
A
A glycoprotein layer produced by the oocyte, crucial for sperm binding.
18
Q
What characterizes a secondary follicle?
A
Fluid-filled cavities begin to form and coalesce into an antrum.
19
Q
What is a Graafian follicle?
A
- A mature, antral follicle ready for ovulation
- Surrounded by corona radiata to provide nutrition
20
Q
What triggers ovulation?
A
A surge in LH stimulates proteolytic activity, expelling the oocyte.
proteolytic enzymes break down the collagen in the walls of the follicle
21
Q
What is the corpus luteum?
A
‘Yellow body’ formed after ovulation, secretes progesterone and oestrogen.
The granulosa cells become the corpus luteum
22
Q
What happens to the corpus luteum if fertilisation doesn’t occur?
A
It degenerates into the corpus albicans (a scar of collagen).
23
Q
What are the key parts of the uterine tube?
A
- Fimbriae: finger-like projections that capture the oocyte
- Infundibulum: funnel-shaped opening near the ovary
- Ampulla: Widest section
- Isthmus: bridge leading to the uterus
- Intramural section: embedded within uterine wall
24
Q
Where does fertilisation typically occur?
A
In the ampulla of the uterine tube.
25
What are the two main cell types in the uterine tube epithelium?
Secretory (peg) cells and ciliated cells.
26
What increases the speed at which the cilia in the uterine tube beat?
Oestrogen
27
What are the layers of the uterine wall?
Endometrium, myometrium, and perimetrium (serosa).
28
What covers the uterus?
Sheet of broad ligament
29
What is the role of the endometrium?
Site for implantation and menstrual shedding.
30
What is the myometrium made of? What does it do?
- Smooth muscle layer
- Contracts during childbirth
31
What is the perimetrium made of? What does it do?
It is the outer visceral peritoneum, and it supports the uterus
32
What is a uterine fibroid?
A benign tumour (leiomyoma) of smooth muscle in the myometrium.
33
What are the main external genital structures in females?
Labia majora, labia minora, clitoris, mons pubis, vestibule.
34
What male structures are homologous to the female labia and clitoris?
Labia majora = scrotum; clitoris = glans penis.
35
What tissue is the clitoris? What is it covered by?
- Erectile tissue, splits into 2 to anchor onto the bulb of vestibule
- Covered by a prepuce
36
What are the 3 forms of oestrogen? When are they present?
1. Estradiol: dominant during reproductive years
2. Estrone: post-menopausal
3. Estriol: pregnancy
37
What is the function of oestrogen?
- Maturation and release of ova
- Development of female secondary sexual characteristics
- Assists sperm transport from vagina to fertilisation site
- Breast development in anticipation of lactation
38
What is the main function of progesterone? What is it secreted by?
- Secreted by the corpus luteum and the placenta
- Prepares the endometrium for implantation
- Maintains pregnancy by preparing a suitable environment
- Regulates breast development for milk production
39
What are the two main phases of the menstrual cycle?
Follicular phase (day 1–14), luteal phase (day 15–28).
40
What mainly occurs in the follicular phase?
Maturation of follicles and oestrogen release
41
What mainly occurs in the luteal phase?
Corpus luteum present, produces progesterone (and oestrogen)
42
What hormones are involved in the follicular phase?
GnRH (hypothalamus), FSH and LH (anterior pituitary) → stimulate follicle growth, and the follicle releases oestrogen
43
What inhibits FSH?
- Oestrogen (produced by the developing follicle)
- Inhibin
- Progesterone
44
What causes the LH surge?
Rising oestrogen levels exert positive feedback on the pituitary.
45
What does the corpus luteum secrete?
Mainly progesterone (and some oestrogen).
46
What inhibits both LH and FSH?
Progesterone
47
What happens hormonally if no fertilisation occurs?
Corpus luteum degenerates, progesterone and oestrogen levels drop, LH and FSH rise, menstruation begins
48
Where does fertilisation occur?
Upper third of the oviduct (ampulla).
49
What happens to the endometrium in the menstrual phase?
Endometrial lining break down and is shed, bleeding occurs from ruptured blood vessels
50
What happens to the endometrium in the proliferative phase?
- Oestrogen promotes endometrial thickening
- Uterine glands develop but remain active
51
What happens to the endometrium in the secretory phase?
- Progesterone stimulates uterine glands to secrete uterine milk (rich in proteins and glycogen)
- Prepares uterus for embryo implantation
52
What causes endometrial breakdown if implantation does not occur?
- Corpus luteum degrades, and progesterone and oestrogen level drop
- Endometrium breaks down (necrosis), and menstruation begins
53
What is a blastocyst? what does it do?
- The developing placenta
- It secretes hCG by day 9 following fertilisation
54
What is hCG and its function?
Human chorionic gonadotropin; maintains the corpus luteum, ensuring progesterone secretion continues, thereby maintaining the endometrium
55
What directly casues mentruation?
the decline in oestrogen and prgestrone levels associated with the degradation of the corus luteum into the corpus albicans
56
When does implantation occur?
6–9 days post-fertilisation, in the uterine endometrium.
57
What happens when hCG production decreases?
The corpus luteum degrades and the placenta takes over oestrogen and progesterone sectretion
58
What happens to hormone production after the first 8 weeks of pregnancy?
Placenta takes over progesterone and oestrogen production from the corpus luteum.
59
What initiates uterine contractions?
High oestrogen:progesterone ratio → upregulation of oxytocin receptors in the myometrium
60
What is the role of oxytocin in labour?
Stimulates strong uterine contractions in a positive feedback loop.
61
What hormone enhances oxytocin-induced contractions?
Prostaglandin F2-alpha (PGF2α).
62
What stimulates duct and alveoli growth in pregnancy?
Oestrogen and progesterone
63
What stimulates milk production from glands?
Prolactin (from anterior pituitary).
64
What triggers milk ejection?
Oxytocin (from posterior pituitary), stimulated by suckling.
65
Where are sperm cells prodcued?
Lining of the seminiferous tubules
66
What are the layers of the tunica vaginalis?
- Parietal layer
- Visceral layer
67
What are the internal spaces of the testes called?
Lobules
68
Where are sperm cells stored and matured?
Epididymis
69
What is the role of the vas deferens?
It transports mature sperm from the epididymis to the urethra
70
What is the seminal vesicle and what is its function?
A gland that produces a fructose-rich fluid that nourishes sperm and forms 60% of semen
- also contains prostaglandins
71
What does the prostate gland secrete?
A slightly alkaline fluid that helps activate sperm and is part of semen
72
What are the corpora cavernosa and corpus spongiosum?
Erectile tissues in the penis that fill with blood during erection
73
What are the corpora cavernosa and what are their function?
Two cylindrical columns of erectile tissue that run along the top (dorsal side) of the penis and fill with blood during erection, causing the penis to become rigid
74
What is the corpus spongiosum and what is its role?
A single column of erectile tissue that surrounds the urethra and runs along the underside (ventral side) of the penis; it prevents the urethra from pinching closed during erection, allowing for semen to pass through
75
Where is sperm produced?
In the seminiferous tubules
76
What cells are the seminiferous tubules made of? What do these cells do? what are they stimulated by?
- Leydig cells: produce testosterone, stimulated by LH
- Sertoli cells: produce androgen binding protein (ABP), stimulated by FSH
## Footnote
They bind together and promote sperm production
77
What do the seminiferous tubules join to create?
The rete testis (net-like structure)
78
What do the seminiferous tubules connect to?
Epididymis
79
What does the epididymis do?
- Stores, matures, and transports sperm to the vas deferens (aka ductus deferens)
80
Where does the vas deferens travel in relation to the bladder?
It travels superiorly to thew bladder then it passes posteriorly nd medially behind it
81
What lies either side of the vas deferens? what do they do?
Seminal vesicles:
* Produce seminal fluid to nourish the spermatozoa
82
What is seminal fluid high in?
Fructose
83
What is the ejaculatory duct?
Vas deferens + seminal vesicles + prostate gland = ejaculatory duct
84
What runs through the prostate gland and towards the ejaculatory duct?
Prostatic urethra
85
What tissue is the penis made of?
Spongiform tissue
86
What are the penis ligaments?
- Fundiform ligament: forms a sling under the penis
- Suspensory ligament: connects the the base of the penis and the symphysis pubis
87
What system is erection caused by?
Parasympathetic nervous system
## Footnote
Erection = **p**oint = **P**arasympathetic
88
What system is ejaculation controlled by?
Sympathetic nervous system
## Footnote
Ejaculation = **S**hoot = **S**ympathetic
89
What are the two cell types in the seminiferous tubules?
Leydig cells
Sertoli cells
90
What do Leydig cells do?
Produce testosterone
91
What do Sertoli cells do?
Produce androgen-binding protein (ABP)
- binds to testosterone
- promote production of sperm when they bind
92
Which hormone stimulates the Leydig cells?
LH
93
Which hormone stimulates the Sertoli cells?
FSH
