Endocrinoclogy 2

Question 1

what are the factors required for growth and development ?

Answer 1

insulin , sex hormones , thyroid hormones and growth hormones

Question 2

give an example of a growth hormone ?

Answer 2

somatotrophin

Question 3

function of somatotrophin ?

Answer 3

they increase the free fatty acid levels , blood glucose , protein synthesis and calcium and phosphate retention.

Question 4

if the levels of glucose are low then what can be used as energy ?

Answer 4

the free fatty acid

Question 5

how can somatotrophin be used in cattle ?

Answer 5

to increase the protein synthesis and yield to farmers.

Question 6

epiphyseal plate ?

Answer 6

what causes longitudinal bone growth.

Question 7

epiphysis ?

Answer 7

area of the long bone where the bone growth takes place.

Question 8

How does bone growth occur ?

Answer 8

bone growth they grow from the epiphyseal plate and push the new bone outward.

Question 9

what is the epiphyseal plate actively proliferating.

Answer 9

the cartilage tissue

Question 10

why does this occur?

Answer 10

there is a production of chondrocytes which maintain the cartridge matrix.

Question 11

where does the conversion of cartilage to bone occur ?

Answer 11

at the shaft edge of the plate

Question 12

what converts the cartilage to bone ?

Answer 12

the osteoblasts

Question 13

when is growth stopped ?

Answer 13

when the epiphyseal plate is converted to bone

Question 14

what does the growth hormone cause in bones ?

Answer 14

the production of cartilage by chondrocytes , in the epiphyseal plate and the conversion of cartilage to bone in the shaft edge of the plate.

Question 15

what else does the growth hormone cause

Answer 15

an increase in the blood glucose because this is used by the muscle cells. The glucose is converted from glycogen in the liver. Growth hormone also causes an accelerated rate of lipolysis in the adipose tissue and this increases the circulating FFA , this reduces the tissue uptake of glucose.

Question 16

what is insulin like growth factor ( IGF-1) also called ?

Answer 16

somatomedin C

Question 17

where is IGF-1 released from and it’s function ?

Answer 17

the liver and helps the cells to uptake glucose which causes growth through cell division.

Question 18

what causes an inhibition of growth hormone secretion ?

Answer 18

Chronic stress , amino acids , low blood glucose and exercise

Question 19

when does the highest level of growth hormone secretion occur ?

Answer 19

when you are asleep , between 2 and 4 am

Question 20

what does the GHRH act on and effect ?

Answer 20

the pituitary to increase levels of Growth hormone

Question 21

Grehlin ?

Answer 21

the hunger hormone which causes a positive feedback on the growth hormone secretion in the pituitary

Question 22

if the growth hormone deficiency occurs before the epiphyseal closure , what occurs ?

Answer 22

dwarfism and this occurs due to IFG-1 deficiency

Question 23

what does GH deficiency cause ?

Answer 23

causes a lowered or absence action of GH on the liver and there is a deficiency in the IGF-1 secretion by liver

Question 24

is the deficiency inherited ?

Answer 24

it can be or sometimes it isn’t

Question 25

if there is an excess of growth hormone before growth cessation what occurs ?

Answer 25

gigantism occurs as seen in Robert Waldlow

Question 26

if growth hormone excess occurs after growth cessation , what occurs ?

Answer 26

acromegaly which is when the bone size increases in your hands , feet and face

Question 27

what does the thyroid secrete ?

Answer 27

thyroxine and triiodothyronine

Question 28

what is the thyroxine ( T4) converted to T3 ( trioodothyronine by ?

Answer 28

the deiodinase enzyme

Question 29

what are the thyroglobulins ?

Answer 29

dimeric glycoproteins that are produced by the follicular cells of the thyroid , they are used entirely by the thyroid gland

Question 30

what are the actions of the thyroid hormone ?

Answer 30

hormones influence activity of almost every body system , they are required for the synthesis of various key enzyme involved in cellular functions. These include enzymes involved in fatty acid syntheses , Beta adrenoreceptors , glyceraldehyde 3-phosphate dehydrogenase , Na-K ATPase and cardiac sarcoplasmic Ca2+ - ATPase.

Question 31

what does the thyrotrophin releasing hormone cause ?

Answer 31

thyrotropin to be released from the pituitary and this causes thyroxine to be released which extensively binds to plasma proteins`.

Question 32

if there is a thyroid deficiency in foetuses what occurs ?

Answer 32

metabolic rate decreases in foetal development then this affects the neuronal development of the foetus. Also this causes a reduced function of most of the organ systems such as lungs , heart , brain , kidneys and digestive organs.

Question 33

thyroid deficiency occur in newborns ?

Answer 33

leads to congenital hypothyroidism ( cretinism) , this causes impaired growth and development as well as mental retardation.

Question 34

thyroid deficiency in adults ?

Answer 34

congenital hypothyroidism causes severe mental retardation , dwarfism and impaired sexual development.

Question 35

what does a thyroid hormone excess cause?

Answer 35

marked increase in the metabolic rate of tissues causes an increased function of heart , digestive tract , kidneys , lungs and brain.