Brainscape's Knowledge GenomeTM

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


See full index

Repro > Puberty and its disorders > Flashcards

Puberty and its disorders Flashcards

1
Q

what is puberty

A

transition from non-reproductive to reproductive state and is where secondary sexual characteristics develop

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

what happens during puberty

A
  • HPGA is activated
  • The adolescent growth spurt
  • Profound physiological changes (hormone increases)
  • Profound psychological changes
  • The gonads produce mature gametes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are the two major endocrine events of puberty

A
  • adrenarche

- Gonadarche

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

what is adrenarche

A

Awakening of the adrenal due to maturation of adrenal cortex cells (reticularis), there is secretion of adrenal androgens
-> Results in growth of pubic and axillary hair and the growth spurt

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

what is gonadarche

A
  • reawakening of HPGA .’. inc LH/FSH
  • inc LH stimulates steroid sythesis .’. secondary sexual characteristics
  • inc FSH .’. growth of testes, steroid synthesis, folliculogenesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what happens in adrenarche

A
  • increase in adrenal androgen secretion

- androgens secreted from zona reticularis of the adrenal cortex. (newly developed)

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

what androgens increase in adrenarche

A

DHEA (dehydro-epiandrosterone) and DHEAS (dehydro-epiandrosterone sulfate) only without increased cortisol levels

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

at what age does adrenarche occur

A

gradual increase in DHEA and DHEAS levels from 6-15 yrs.

peak at 20-25 years.

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

what is adrenopause

A

the decline in DHEA/DHEAS after its peak

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

what is pubarche

A

development of pubic hair

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

why does pubarche occur

A

as a result of adrenarche

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

why is pubarche associated with ache

A
  • Increased sebum production, often leading to acne

- Infection and abnormal keratinization, also causes acne

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

what is precocious puberty

A

early puberty

before 8 in girls or 9 in boys

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

when does gonadarche occur

A

several years after adrenarche (typically around 11 years of age)

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

what is gonadarche

A

reactivation of the HPG axis, reactivation of hypothalamic GnRH
.’. activated gonadal steroid production
.’. production of viable gametes
.’. ability to reproduce

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

from which structure is GnRH released

A

hypothalamus. Pulsatile manner

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

when is HPGA originally activated

A

16th gestational week

pulsatile release occuring in foetus until 1-2 years when it ceases

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

when is HPGA reactivated

A

11 years in gonadarche

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

why is LH an indicator of GnRH secretion

A

pulse of GnRH =pulse of LH

.’. LH levels increase in puberty

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

what stimulates the onset of puberty

A

unclear. could be:
- maturation of GnRH sythesising neurones
- environment/genetics
- Body fat/nutrition
- leptin
- Gut hormone
- kisspeptin

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

what is the effect of low body fat on ability to reproduce

A

= reduced response to GnRH .’. gonadotrophin .’, amenorrhoea
women lost reproductive ability.
When nourishment occurs or the exercise stops, periods start again.

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

what % body fat is required for menarche and to maintain female reproduction

A

menarche - 17%

maintain female reproductive ability - 22%

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

what is kisspeptin

A

a neurohormone.

directly regulates GnRH secretion

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

where does kisspeptin exert is action and what does it do

A

receptors are on dendrites of GnRH neurones and so directly regulates GnRH secretion.

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

mutations in GPR54 (kisspeptin receptor) or the gene coding for kisspeptin results in:

A
  • abnormal development of GnRH neurones -> hypogonadism
  • failure to enter puberty
  • hypothalamic hypogonadism
  • Activating mutations of kisspeptin receptor -> precocious puberty
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

what is meant by consonance of puberty

A

all changes that occur in puberty occur in the same order (just at different ages)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

what is the first change of puberty in females

A

breast bud formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

what is the first change of puberty in males

A

testicular volume increases to above 4ml

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

how many tanner stages of puberty are there

A

5
first being hasnt entered puberty
last being puberty is complete

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

how does the first tanner stage of puberty present

A

(females) no breast tissue
(males) prepubertal genital development
(both) no pubic hair

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

how does the second tanner stage of puberty present

A 
(females) areolar enlargement
breast bud
(males) testis enlarged to 4ml.
 scrotum larger. skin coarser.
(both) no pubic hair
32
Q

how does the third tanner stage of puberty present

A

(females) enlargement of breast and areolar as a single mould
(males) penis enlarged in length. continued growth of penis and scrotum
(both) curly pigmented hairs across pubes

33
Q

how does the fourth tanner stage of puberty present

A

(females) projection of areola above breast
(males) growth of penis in length and diameter. pigmentation of scrotum
(both) small adult configuration of hair

34
Q

how does the fifth tanner stage of puberty present

A

puberty complete

(females) papilla projects out of areola forming part of breast contour)
(males) testis, scrotum and penis at adult size
(both) hair in adult configuration with spread onto thighs

35
Q

what is the first outward sign of estradiol activity in females

A

breasts enlarge

36
Q

physical changes in females at puberty

A
  • breasts enlarge
  • growth of pubic/axillary hair
  • uterus enlarges
  • cytology changes in uterus and secretions
  • height increase
  • changes in body shape (widened hips)
37
Q

how does pubertal height increases differ in boys and girls

A

Growth spurt occurs earlier in girls than in boys

38
Q

physical changes in males at puberty

A
  • growth of external genitalia
  • vans deferens lumen diameter increases
  • Growth of facial/body hair
  • Growth of pubic/axillary hair
  • larynx enlargement
  • height increase
  • fertility
39
Q

how does male external genitalia change at puberty

A

increase in testicular volume to above 4ml

growth of penis, scrotum and scrotal skin changes

40
Q

how does the male larynx change at puberty

A
  • androgens = enlargement of larynx
  • development of adams apple (a projection of the thyroid cartilage)
  • voice deepens
41
Q

at what age is the peak height growth in males and females

A

females - 12yrs

males - 14yrs

42
Q

how does fertility change at puberty for males

A

Testosterone from Leydig cells stimulates meiosis and spermatogenesis in Sertoli cells

43
Q

what hormones cause the growth spurt (males and females)

A

complex interaction between growth hormone and oestrogen

44
Q

effect of oestrogens on epiphyseal growth

A

biphasic effect
1 - early puberty has low levels of oestrogens -> support linear bone growth and bone maturation
2 - later puberty has high levels of oestrogen -> epiphyseal fusion = bone fusion and decrease in growth spurt

45
Q

what are Pilosebaceous Units (PSUs)

A

The structure consisting of hair, hair follicle, arrector pili muscles, and sebaceous gland is an epidermal invagination

46
Q

how do androgens affect differentiation of pilosebaceous Units (PSUs)

A

Androgens will cause Vellus PSU to differentiate into

  • Terminal PSUs that form the beard and moustache
  • APO-PSUs which form the pubic and axillary hair
47
Q

what is vellus hair

A

Vellus hair is short, thin, slight-colored, and barely noticeable thin hair that develops on most of a person’s body during childhood.

48
Q

what are the psychological changes of puberty

A
  1. Increasing need for independence
  2. Increasing sexual awareness/interest
  3. Development of sexual personality
49
Q

what is precocious sexual development

A

pubertal changes occur early (before 8 in girls and 9 in boys) but in consonance

50
Q

what are the two types of precocious puberty

A

1 - Gonadotrophin-dependent (central) precocious puberty

2 - Gonadotrophin-independent precocious sexual development

51
Q

what is Gonadotrophin-independent precocious sexual development

A

early sexual development where there is a loss of consonance

52
Q

what is Gonadotrophin-dependent (central) precocious puberty

A

early sexual development in consonance due to reawakening of HPGA

53
Q

what may cause Gonadotrophin-dependent (central) precocious puberty

A
  • excess GnRH secretion (idiopathic or secondary

- excess gonadotrophin from a pituitary tumour

54
Q

what may cause Gonadotrophin-independent precocious sexual development

A
  • testotoxicosis
  • McCune Albright Syndrome
  • A sex steroid secreting tumour
  • exogenous steroids
55
Q

what is testotoxicosis

A

is a type of gonadotropin-independent precocious development

- activating mutation of LH receptor, causing early virilsation of external genitalia

56
Q

what is McCune Albright Syndrome

A

-adenylyl cyclase and cAMP constantly active

= café au lait skin pigmentation + other endocrine disorders such as fibrous dysplasia

57
Q

what is pseudo precocious puberty

A

partial pubertal development that results from autonomous (gonadotropin-independent) production of estrogen in prepubertal girls.

58
Q

what may cause pseudoprecocious puberty

A
  • Premature adrenarche/pubearche

- result of CAH or Cushing’s

59
Q

how may we investigate precocious sexual development

A
  • auxology
  • pubertal staging analysis
  • estimate bone age
  • LH, FSH and sex steroid measurements
  • testing LH response to 100micrograms of GnRH
  • Measure adrenal steroids
  • MRI of hypothalamic-pituitary area
  • Ultrasound scans of pelvis
60
Q

what is auxology

A

accurate measurement of height, body proportions, weight and how they all come together

61
Q

what is pubertal staging analysis

A

find which stage individual is at in puberty, tanner scale or orchidometer may be used here

62
Q

what can we use to measure bone age

A

DEXA scan

63
Q

why may we measure LH, FSH and sex steroid in precocious puberty

A

tell us if the HPG axis has been re-awakened or there is an isolated increase in one of them

64
Q

why may we test LH response to GnRH in precocious puberty

A
  • peak in LH in response would be indicative of central precocious puberty
  • LH suppressed in testotoxicosis
65
Q

why may we do an ultrasound of pelvis in response to precocious puberty

A

see their maturation and thickness of uterus giving an indication of levels of oestrogen.

66
Q

how may we treat precocious puberty

A
  • Anti-androgens for premature adrenarche
  • 5a-reductase inhibitor to stop virilisation of external genitalia (eg in testotoxicosis)
  • Aromatase inhibitor; inhibit oestrodiol + oestrogen production
  • long-acting GnRH analogue in central precocious puberty to down-regulate HPG axis
67
Q

what may be treatment for premature adrenarche

A

antiandrogens

68
Q

what may be treatment for virilisation of external genitalia (eg in testotoxicosis

A

5a reductase inhibitor

69
Q

what may be used as a treatment for central precocious puberty

A

long acting GnRH

to downregulate HPGA

70
Q

what is meant by pubertal delay

A

absence of secondary sexual maturation (characteristics) by 13yrs in girls (or absence of menarche by 18yrs) or 14yrs in boys

71
Q

reasons for pubertal delay

A
  • constitutional delay
  • hypogonadotrophin hypogonadism (low LH&FSH)
  • Hypergonadotrophin hypogonadism (high LH and FSH)
72
Q

why may Constitutional delay = pubertal delay

A

Affects both growth and puberty

  • where reactivation of HPG axis doesn’t occur
  • could be idiopathoc or secondary to a chronic disease
73
Q

what may Hypogonadotrophin hypogonadism = pubertal delay

A

this is low levels of gonadotrophin hormones, may be a result of a genetic mutation

74
Q

why may Hypergonadotrophin hypogonadism = pubertal delay

A

= high LH/FSH
normal higher functioning of hypothalamus and pituitary
problem lies at gonads = low sex steroid levels

75
Q

how does turners syndrome (45X0) present

A
  • Being shorter than normal

- Having underdeveloped or ‘streak’ ovaries

76
Q

how may we investigate delayed puberty

A
  • Start of by looking at family history, any dysmorphic features, anosmia
  • auxology
  • pubertal staging
  • bone age estimation
  • LH. FSH, Sex steroid measurements
  • LH response to 100micrograms of GnRH
  • MRI scans of hypothalamo-pituitary area
  • ultrasound of pelvis, tell us about oestrogenic activity
77
Q

how may we treat delayed puberty

A
  • Give testosterone in males
  • Give oestrogens in females to cause breast development, growth spurt etc.
  • Give oxandralone (a synthetic steroid)
  • wait for puberty to start

Repro (13 decks)

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