Puberty

Question 1

What are some physical changes in puberty

Answer 1

Significant regression of lymphoid tissue
Brain development complete
Growth of CNS
Heart, lungs and viscera increase in size and mass

Question 2

What is one metabolic factor that affects puberty initiation

Answer 2

Leptin appears to play a permissive role in puberty initiation and maintenance of reproductive function

Question 3

What does the KNDy Neuron release

Answer 3

Kisspeptins and Dynorphin

Question 4

What has a negative feedback of GnRH neurons

Answer 4

Dynorphin

Question 5

What stimulates GnRH

Answer 5

Kisspeptin

Question 6

What reduces inhibition of gonadotrophs by GnIH

Answer 6

Leptin

Question 7

A decrease in what signal reduces GnIH

Answer 7

Melatonin

Question 8

What inhibits GnRH (apart from dynorphin)

Answer 8

GnIH

Question 9

What does GnIH work on

Answer 9

Kisspeptin, GnRH, Gn

Question 10

What receptors does Kisspeptin bind to

Answer 10

GPCR KISS1R, expressed by GnRH neurones

Question 11

When is mini puberty

Answer 11

postnatal, 1-6 months

Question 12

Does gonadarche or adrenarche come first and by how much

Answer 12

Adrenarche, 2 years

Question 13

What is the first sign of puberty in females

Answer 13

Thelarche

Question 14

Does thelarche or menarche come first and by how much

Answer 14

Thelarche, 2 years

Question 15

Which tanner stage does growth spurt take place in

Answer 15

Stage 2-3 in girls and 3-4 in boys

Question 16

Which tanner stage is start of gonadarche

Answer 16

Stage 2

Question 17

Which stages are thelarche and menarche

Answer 17

3-4 respectively

Question 18

When does pubic hair grow in males and does it reflect adrenarche or gonadarche

Answer 18

Stage 2, can reflect both

Question 19

does pubic hair or genital develop first in males and by how many year

Answer 19

Genitals, 1-1.5 years

Question 20

What happens in gonadarche in males

Answer 20

activation of HPG axis leads to enlargement of testes and scrotum

Question 21

What is produced during adrenarche and where

Answer 21

DHEA, androstenedione in ZR

Question 22

Does peak strength velocity or peak height velocity occur first and by how much

Answer 22

Peak height velocity, a year or two

Question 23

Effect of estrogen on cholesterol

Answer 23

Protects the heart from cholesterol and regulates cholesterol production regulation

Question 24

Causes of precocious puberty

Answer 24

CNS or pituitary lesion. McCune-Albright syndrome, Gn-secreting tumours

Question 25

Causes of contrasexual development in girls

Answer 25

PCOS, cushing, acromeglay, exogenous androgens, adrenal or ovarian tumours, hyperprolactinaemia

Question 26

Causes of contrasexual development in boys

Answer 26

estrogen secreting tumours

Question 27

Which type of ossification occurs in physis of long bones

Answer 27

Endochondral ossification- leads to longitudinal growth

Question 28

Which type of ossification occurs in bone fractures in a plaster cast and which occurs when bone fracture is treated with rigid plate and screws

Answer 28

EC, IM

Question 29

What do we call bone that grows in width and what type of ossification

Answer 29

Subperiosteal bone growth

Question 30

What happens in primary spongiosa and secondary spongiosa

Answer 30

Osteoprogenitor cells invade calcified materix and lay down woven bone.
In 2* spongiosa, woven bone is remodelled into lamellar bone

Question 31

How does GH affect growth during puberty

Answer 31

Has effects on the physis

Question 32

How do steroids affect growth

Answer 32

Affects cartilage cell division