Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

BRS > The reproductive system > Flashcards

The reproductive system Flashcards

1
Q

What is found in seminal fluid?

A

Fructose- nutrients for sperm
Citric Acid- nutrients for sperm
Bicarbonate- neutralises acidic pH of vagina
Fibrinogen- thickening agent
Fibrinolytic enzymes- helps sperm break through and find egg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is erection and ejaculation due to ?

A

Erection is due to parasympathetic stimulation

Ejaculation is due to sympathetic stimulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What structures are found in the penis?

A 
2x Corpora cavernosa
1x Corpora spongiosum
Testes surrounded by 3 connective tissues:
- Tunica vasculosa (innermost)
- Tunica albuginea
- Tunica vaginalis (outermost)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the spermatic cord?

A 
Formed at deep inguinal ring
Contains several structures:
- testicular artery
- pampiniform plexus
- autonomic and GF nerves
- Lymph vessels
- Vas deferens
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What supplies the testes?

A

Arterial blood supply: testicular arteries from the aorta via spermatic cord
Lymphatic drainage: para-aortic lymph nodes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Where can the ovaries be found?

A

Inside the peritoneal cavity (remainder outside)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How are the Fallopian tubes structures and what is their role?

A

Fallopian tubes have cilia and spiral muscle

Peristalsis and wafting of cilia causes oocytes to move down the tube

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Where does fertilisation occur in the female reproductive tract?

A

In the ampulla (wider part of Fallopian tube)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How is the uterus supported?

A

Uterus supported by tone of pelvic floor (elevator ani and coccyges) and ligaments (broad, round and uterosacral)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Why does the endometrium shed?

A

Endometrium sheds at menses due to vasoconstriction of arterioles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What structures can be found in close proximity to the cervix?

A

1cm lateral to the cervix is ureter

All areas superior to cervix are sterile

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What supples blood to the ovaries, uterus and vagina?

A

Ovaries: Ovarian arteries (from aorta)

Uterus/ vagina: uterine arteries (from internal iliac artery)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What structures carry lymphatic drainage in the ovaries, uterus and vagina?

A

Ovaries: Para-aortic lymph nodes

Uterus/ Vagina: Iliac, sacral, aortic and inguinal lymph nodes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How are spermatogonia produced?

A

Gametogenesis occurs at puberty
Spermatogonia undergo differentiation and self- renewal- continuous fertility through life due to subsequent spermatogenic cycles throughout life
Produces ~1500 mature sperm/ sec

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How are oogonia produced?

A 
BEFORE BIRTH:
multiplication of oogonia ~6 mil/ovary
Primary oocytes are formed within ovarian follicles (= primidoral follicle)
These begin meiosis (halted at prophase)
Some primordial follicles degrade 
At birth ~2 mil/ovary remain
AT PUBERTY:
By puberty <0.5mil/ovary remain
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is gametogenesis known as in males?

A

Spermatogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How are spermatozoa produced?

A

Spermatogonium (44XY) divide by mitosis to form primary spermatocytes (44XY)
Primary spermatocytes undergo 1st meiotic division to form secondary spermatocytes (22X or 22Y)
Secondary spermatocytes undergo second meiotic division to form spermatids (22X OR 22Y)
Spermatids then differentiate to spermatozoa (22X OR 22Y)
This process occurs in seminiferous tubules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Where can a Sertoli cell be found and what’s its function?

A

Location: within seminiferous tubules
Have FSH receptors
Support developing germ cell:
- assist movement of germ cells to tubular lumen
- transfer nutrients from capillaries to developing germ cells
- phagocytosis of damaged germ cells
Hormone synthesis:
- Inhibin (inhibits FSH) and activin (activates FSH)
- Anti- mellerian hormone (AMH)
- Androgen-binding protein (ABP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Where can leydig cells be found and what is their function?

A

Location: between seminiferous tubules
Pale cytoplasm and cholesterol rich
Have LH receptors
Hormone synthesis: On LH stimulation, secrete androgens:
- Testosterone
- Androstenedione
- Dehydroepiandrosterone (DHEA) (can be aromatised to oestrogen)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is gametogenesis in females called?

A

Oogenesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How are Ova formed?

A

In 2nd trimester of pregnancy, oogonium (44XX) undergoes mitosis to form primary Oocytes (44XX) (primary oocytes form primordial follicles)
Primary oocytes undergo 1st meiotic division to form secondary oocytes (22X) (stay in prophase until menarche after which they continue rest of cycle)
After fertilisation, secondary oocytes undergo 2nd meiotic divisor to form ootids (22X)
Ootids undergo differentiation to form Ova (22X)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How does folliculogenesis (development of follicles) occur?

A
  1. Primordial follicle- primary oocyte at birth
  2. Primary (preantral) follicle- primary oocyte and layers of granuloma cells and outer theca cells
  3. Secondrary (antral) follicle- Fluid filled cavity (antrum) develops, FSH and LH receptors develop
  4. Mature (Graafian/preovulatory) follicle- forms due to LH surge, secondary oocyte formed
  5. Ruptures surface of ovary
  6. Corpus Luteum- produces progesterone and oestrogen (stimulate by LH/HCG). In pregnancy progesterone and oestrogen production taken over by placenta
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is progesterone formed by and what is its role?

A

Corpus luteum is source of progesterone

Progesterone is important for pregnancy, supports uterus in preparation for implantation

24
Q

How do we assess if someone has ovulated?

A

Measure:
Day 21 progesterone: rise in progesterone if corpus lutem has formed
Ultrasound- can see corpus luteum

25
Q

What 2 cells are found in the ovary?

A

Theca cells

Granulosa cell

26
Q

Where can theca cells be found and what is the function?

A

Location: associated with outer part of ovarian follicles

Support folliculogeneis:
- structural and nutritional support of growing follicle
Hormone synthesis:
- LH stimulates synthesis of androgens. Overactivity= high androgen levels (hyperandrogenism)

27
Q

Where can granuloma cells be found and what is their function?

A

Location: associated with inner part of ovarian follicles

Hormone synthesis:
- FSH stimulates granuloma cells to convert androgens to oestrogen (by aromatase)
-Secrete inhibin and activin (effects on FSH)
After ovulation turn into granuloma lutein cells that produce:
- progesterone (neg. feedback, promote pregnancy by maintaining endometrium)
- relaxin (helps endometrium prepare for pregnancy and softer pelvic ligaments/cervix)

28
Q

What is the hypothalmo- pituitary- gonadal axis?

A
  1. Kisspeptin nerves are at top of axis- secrete kisspeptin
  2. kisspeptin acts on kisspeptin receptors on GnRH (gonadotrophin releasing hormone) nerves
  3. GnRH nerves secretes GnRH into hypophyseal portal circulation- secretion is in pulsatile fashion, frequency and amplitude governs downstream actions
  4. GnRH stimulates gonadotrophs in anterior pituitary which release FSH and LH (also in pulsatile fashion)
  5. LH and FSH travel to gonads through systemic circulation and act on gonads to cause production of hormones (testosterone, oestrogen, progesterone, activin and inhibin)

There’s negative feedback from oestrogen, progesterone and testosterone on kisspeptin nerves or gonadotrophs in anterior pituitary

29
Q

How does hormone production change across the day?

A

Oestrogen and progesterone are diurnal

30
Q

What happens in hyperprolactinaemia?

A

High levels of prolactin causes prolactin to bind to prolactin receptors on kisspeptin neurones in hypothalamus
This inhibits kisspeptin release
This leads to a downstream decrease in GnRH, LH, FSH, Testosterone and oestrogen
This can lead to oligo-amenorrhoea, low libido, infertility and osteoporosis

31
Q

What happens in the menstrual cycle?

A

Day 1: progesterone drop leads to first day of bleeding (blood and cellular debris from necrotic endometrial lining)
Ovulation- approx. day 14, theres an LH surge and smaller FSH surge along with high oestrogen levels
Progesterone increase occurs after ovulation, increases then drops- causes pain and shedding
Menstruation cycle lasts ~28 day, can range from 21 to 35 days

32
Q

What do we call a menstrual cycle over 35 days?

A

oligomenorrhoea

33
Q

What drives the menstrual cycle?

A

Hypothalmic kisspeptin and GnRH
Pituitary LH and FSH
Ovarian oestrogen, progesterone, activin and inhibin

34
Q

What occurs in the ovarian cycle?

A

Follicular phase- follicle forms
Ovulation (pre-ovulatory phase)
Leuteal phase

35
Q

What occurs in the uterine cycle?

A

Menstrual phase
Proliferative phase
Secretory phase

36
Q

How is semen produced?

A

Spermatozoa travel through seminiferous tubules, tubular resorption results in concentration of sperm driven by oestrogen
Nutrients e.g. fructose and glycoprotein are secreted into epididymal fluid

37
Q

How far does sperm travel?

A

It travels 100 000 times its length from testes to Fallopian tube

38
Q

What does semen consist of?

A

Spermatozoa
Seminal fluid
Leucocytes
Potential viruses e.g. hep B, HIV

39
Q

How many spermatozoa reach the ovum?

A

1/100 enter the cervix
1/10000 go from cervix to ovum
Overall 1/1 million reach ovum

40
Q

Where does seminal fluid come from?

A 
Small contribution from epidermis/ testes
Mainly from accessory sex glands:
seminal vesicles
prostate
bulbourethral glands
41
Q

What happens in the capacitation of sperm?

A

Capacitation of sperm is the process by which sperm achieves the ability to fertilise in the female reproductive tract
Capacitation involves:
loss of glycoprotein coat
change in surface membrane characteristic
develop whiplash movements of tail

Its oestrogen dependant and Ca2+ dependent

42
Q

Where does capacitation take place?

A

Takes place in ionic and proteolytic environment of Fallopian tube

43
Q

What happens after capacitation?

A

Acrosome reaction:
sperm binds to ZP3
there is a Ca2+ influx into sperm (Stimulated by progesterone)
Release of hyaluronidase and proteolytic enzymes (from acrosome) which breaks down zona pellucida
Spermatozoon penetrates zona pellucida

44
Q

Where does fertilisation occur and what happens?

A

occurs in the Fallopian tube
Triggers cortical reaction:
Cortical granules release molecules which degrade zone pellucida (e.g. ZP2 and 3)
This prevents further sperm binding as here’s no receptors
It triggers the final maturation of secondary oocyte to form ovum
Ends with diploid zygote

45
Q

What happens after fertilisation?

A

Development of conceptus
Continues to divide as it moves down Fallopian tube to uterus (3-4 days)
Receives nutrients from uterine secretions
This free-living phase can last for 9-10 days

46
Q

What happens in implantation?

A

Attachment phase: outer trophoblast cells contact uterine surface epithelium
THEN
Decisualisation phase: changes in underlying uterine stromal tissue

This requires progesterone domination in the presence of oestrogen

47
Q

What happens to the blastocyst?

A

Inner cell mass forms embryo

Trophoblast cells form placenta

48
Q

What occurs in attachment?

A

2 factors allow the adhesion of blastocyst to endometrial lining:
Leukaemia inhibitory factor (LIF) from endometrial cells stimulates adhesion of blastocyst to endometrial cells

Interleukin-11 also from endometrial cells is released into uterine fluid and may be involves
Many other molecules are involved into the process (HB-EGF)

49
Q

What occurs in decidualisation?

A

Endometrium changes due to progesterone

  • glandular epithelial secretion
  • glycogen accumulation in stromal cell cytoplasm
  • growth of capillaries
  • increased vascular permeability
50
Q

What factors are involved in decidualisation?

A

IL 11, histamine, certain prostaglandins and TGF beta

51
Q

What hormone is present in pregnancy?

A

hCG- human chorionic gonadotrophin produced by placenta by trophoblasts

52
Q

How does progesterone and oestrogen production vary during pregnancy?

A

In the first 40 days:
Produced in corpus luteum- stipulated by hCG which acts on LH receptors
Essential for developing fetoplacental unit
Inhibits maternal LH and FSH
From day 40:
Placenta takes over

53
Q

What physiological changes occur in maternal hormones?

A

Increase:

  • ACTH
  • Adrenal steroids
  • Prolactin
  • IGF1
  • Iodothyronines
  • PTH related peptides

Decrease:

  • Gonadotrophin
  • Pituitary GH
  • TSH
54
Q

What is labour also known as?

A

Parturition

55
Q

What is the main hormone in parturition?

A

Oxytocin from posterior pituitary

Theres an increase in oxytocin receptors on myometrial and endometrial cells towards end of pregnancy

56
Q

What is oxytocin important for?

A

Uterine contraction
Cervical dilation
Milk ejection

BRS (60 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions