Brainscape's Knowledge GenomeTM

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


See full index

Reproductive Week > Reproductive endocriology > Flashcards

Reproductive endocriology Flashcards

1
Q

what are the 3 main cases of hormones in the body?

A

proteins/polypeptides
steroids
derivatives of the amino acid tyrosine

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

what are some examples of protein hormones/polypeptides?

A

insulin
growth hormone
Thyroid stimulating hormone

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

what are some examples of steroid hormones?

A

cortisol
oestrogen
progesterone

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

what are some examples of dervivates of the amino acid tyrosine hormones?

A

thyroxine
adrenaline

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

which kinds of hormones are hydrophilic?

A

proteins/polypeptides (insulin)
derivatives of the amino acid tyrosine (adrenaline)

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

what kind of hormones are hydrophobic?

A

steroid hormones (oestrogen)

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

where are steroid hormones derived from?

A

cholesterol
enzymatic modification of cholesterol

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

what is the structure of polypeptide hormones?

A

chain of amino acids

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

where are derivatives of tyrosine hormones synthesised?

A

in the adrenal glands as well as the thyroid

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

where do receptors tend to be located?

A

present in serum and tissues at low concentrations so must have high affinity

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

where does the synthesis of steroid hormones generally occur?

A

mitochondria and the SER

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

why are steroid hormones not stored before secretion?

A

because they are lipid soluble and are therefor permeable to membranes

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

what is the mechanism of action of steroid hormones?

A
  1. steroid hormone enters target cell
  2. binds to a receptor present in target cell
  3. the hormone-receptor complex enters the nucleus
  4. binds to DNA in the nucleus and activates transcription
  5. new mRNA is made which moves to the cytoplasm
  6. translation produces new proteins
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are circulating oestrogen?

A

a mix of oestrone and oestradiol

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

where is oestrogen synthesised?

A

directly from the ovary or converted from androstenedione

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

how is oestrogen produced from androstenedione?

A

estradiol produced by the ovary, deduced by direct synthesis in the developing follicles or through conversion of oestrone
the enzyme aromatase is responsible for this conversion

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

what is oestrogen involved in?

A

development of female secondary sex characteristics
control of the menstrual cycle
pregnancy
bone strength

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

what are the 3 major endogenous oestrogens?

A

oestrone
oestradiol
oestriol

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

which type of oestrogen is the most prevalent and potent?

A

oestrodiol

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

what is the hormone that covers androgen to oestrogen?

A

aromatase

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

what are some examples of oestrogens?

A

testosterone, androstenedione and dihydrogen, dihydrotesterone

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

where are androgens synthesised?

A

testis
ovary
adrenal gland

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what is the role of androgens?

A

regulate male primary sec organs and secondary sexual characteristics
important in libido and sexual arousal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

where are progestins (progestogens) synthesised?

A

from cholesterol via pregenolone
-produced primarily in the Corpus luteum of ovary, the adrenal glands and in the placenta during pregnancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

what are the roles of progestones?

A

maintaining endometrium to support pregnancy
important for mammary gland development in pregnancy

25
Q

where is the hypothalamus located?

A

located anterior and inferior to the thalamus

26
Q

where is the hypothalamus located?

A

sits above the pituitary gland and. the pituitary gland is cradled within the cellar of the bone of the skull

27
Q

what are the 2 lobes of the pituitary gland?

A

arise from distinct parts of the embryonic tissue and there is a posterior and anterior lobe

28
Q

what is the posterior pituitary gland lobe made up of?

A

neural tissue

29
Q

what is the anterior pituitary gland lobe made up of?

A

glandular tissue

30
Q

roughly how large is the pituitary gland?

A

generally the size of a pea

31
Q

what are the main roles of the hypothalamus?

A

-links the nervous system to the endocrine system
-located below the thalamus
-part of the limbic system
-controls body temp. hunger, thirst, sleep etc

32
Q

what is the main roles of the pituitary gland?

A

-endocrine gland
-suspended from the underside of the brain by the pituitary stalk
-has an anterior and a posterior portion

33
Q

what connects the hypothalamus to the pituitary gland?

A

a stem called the infundibulum
sometimes called the pituitary stalk

34
Q

what is the unique vasculature between the hypothalamus and pituitary?

A

hypothalamo-hypophysial portal system which allows connection between them

35
Q

what hormones are released by the posterior pituitary?

A

ADH
oxytocin

36
Q

what hormones are released by the anterior pituitary?

A

FSH/LH
growth hormone
thyroid stimulating hormone
adrenocorticotrophic hormone
prolactin

37
Q

what does oxytocin do?

A

promotes uterine contractions during labour
milk ejection during lacation

38
Q

what does FSH/LH do?

A

regulation of gamete production and reproductive hormones

39
Q

what does growth hormone do?

A

stimulates cell proliferation and regulates growth

40
Q

what does thyroid stimulating hormone do?

A

stimulates synthesis and release of thyroid hormones

41
Q

what does adrenocorticotrophic hormone do?

A

stimulates cortisol secretion from the adrenal gland

42
Q

what does prolactin do?

A

stimulates milk production during lactation

43
Q

what is the hypothalamic-pituitary axis?

A

command centre of the endocrine system
coordinates messages of the endocrine and nervous system together
stimulus is received by NS will pass through the hypothalamic pituitary complex to be translated into hormones that elicit a response

44
Q

what regulates reproduction?

A

hypothalamic-pituitary-honadal axis

45
Q

how does the hypothalamic-pituitary-honadal axis work?

A

-hypothalamus secretes gonadotrophin (GnRH) which stimulates anterior pituitary to release FSH and LH
-thr ovary or testis (and placenta) respond to the levels of gonadotrophin and secrete steroid sex hormones

46
Q

where is GnRH secreted from?

A

neurosecretory cells within the hypothalamus

46
Q

what Is GnRH?

A

a 10 amino acid peptide with a short half life

47
Q

what is the hypothalamic control of GnRH?

A

It is secreted into the portal vessel
secreted in a pulsatile manner
activates its receptor (GnRHR) within the anterior pituitary which stimulates the release of gonadotrophin

48
Q

what level of hormonal control of reproduction do we consider the pituitary gland?

A

2nd level

49
Q

what does the anterior pituitary gland do?

A

secrete peptide hormones
-FSH
-LH
-acts on the ovary and testis

50
Q

what does the posterior pituitary gland do?

A

secretes oxytocin
-involved In childbirth and lactation

51
Q

what is the role of FSH in males?

A

-stimulates primary spermatocytes to undergo meiosis
-enhances production of androgen binding protein in Sertoli cells of the testis

52
Q

what does FSH do in females?

A

-initiates recruitment and supports growth of ovarian follicles
(granulose cells)

53
Q

what does LH do in males?

A

-acts on the leydig cells of the testis to regulate production of testosterone

54
Q

what does LH do in females?

A

-supports ovarian theca cells
-LH surge triggers ovulation
-trigger for ovulation

55
Q

what effect does LH have on theca cells?

A

produce androgens which get passed to the granulose cells t produce oestrogens

56
Q

what effect does rising oestrogen or testosterone have?

A

negative feedback on the hypothalamus and inhibits the release go GnRH and FSH, LH

57
Q

when do we get positive feedback for FSH and LH?

A

to allow ovulation
breast feeding

58
Q

which pituitary hormone stimulates Sertoli cells in the testis?

A

FSH

Reproductive Week (8 decks)

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