WEEK 7: 7.1 Main Endocrine Glands and Hormone Types

Question 1

What is responsible for most communication within the body?

Answer 1

Extracellular chemical messengers

Question 2

What are extracellular chemical messengers?

Answer 2

molecules that are secreted into the extracellular space, that establish control pathways over short/long distances, & include neurotransmitters, autocrine and paracrine mediators and hormones

Question 3

What are the 3 different types of local/long distance chemical messengers?

Answer 3

paracrine
endocrine
autocrine

Question 4

What is a paracrine mediator?

Answer 4

It is a type of chemical signaling involving secreted chemicals acting locally on nearby cells for eg. Histamine

Question 5

What is autocrine?

Answer 5

Chemical signalling in which secreted chemicals act back on the same cells that secreted them. eg. white blood cells synthesising a growth factor.

Question 6

What is endocrine?

Answer 6

chemical signaling in which chemicals defuse into the bloodstream, to reach target cells throughout the body

Question 7

What is the definition of a hormone?

Answer 7

blood borne chemical messengers that carry info to target organs

Question 8

Compare the speed of communication and duration of effect of hormones to the nervous system

Answer 8

speed of communication is slower than the nervous system and the duration of effect is longer

Question 9

Name 7 different functions of the endocrine system

Answer 9

regulation of growth and development, maintaining appropriate water and electrolyte balance, muscle development and strength, blood glucose control, temperature regulation, regulation of mood and emotions, reproductive function

Question 10

what are central endocrine glands?

Answer 10

endocrine structures located in the brain

Question 11

What are the endocrine glands resting outside the brain called?

Answer 11

peripheral endocrine glands

Question 12

what are some non-classical endocrine glands

Answer 12

heart, stomach, intestines, kidney, adipose tissue in skin

Question 13

What hormone does the heart secrete

Answer 13

ANP

Question 14

What hormone does the kidney secrete

Answer 14

renin

Question 15

what hormones do the stomach and small intestines secrete

Answer 15

gastrin and cholecystokinin - influence digestion

Question 16

what does the placenta do in the endocrine system?

Answer 16

it is a temporary endocrine gland during pregnancy that secretes hormones critical for physiological adaptation of the mother and for maintenance of the pregnancy

Question 17

What hormones does the liver secrete, and what are their functions?

Answer 17

insulin like growth factor- growth and repairment of tissues
thrombopoietin- stimulates the production of platelets & is needed for blood clotting

Question 18

What are some examples of exocrine glands ?

Answer 18

salivary glands, sweat glands, sebaceous glands and mammary glands

Question 19

What is a key difference between endocrine and exocrine glands?

Answer 19

exocrine glands have ducts in which substances they secrete travel along, whereas endocrine glands are ductless and release hormones into surrounding fluid

Question 20

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

Answer 20

peptides and proteins, steroids and amines

Question 21

what are peptide and proteins composed of?

Answer 21

chains of amino acids

Question 22

what are steroids and amines made of, respectively?

Answer 22

cholesterol, tyrosine/tryptophan

Question 23

How long is a peptide hormone’s half life?

Answer 23

a few minutes

Question 24

T or F: peptide hormones have amino acid chains of varying lengths

Answer 24

T

Question 25

What does it mean when a peptide hormone is referred to as lipophobic?

Answer 25

It can be transported freely in blood, but cannot cross the plasma membrane

Question 26

Where are peptide hormones stored?

Answer 26

in secretory vesicles

Question 27

Peptide hormones are synthesised as ___ and can be modified to ____

Answer 27

preprohormone in ER and prohormone in golgi apparatus

Question 28

How are peptide hormones released

Answer 28

via exocytosis of secretory vesicles

Question 29

What does it mean when it says steroid hormones are synthesized de novo?

Answer 29

as needed in the smooth ER of the gonals, adrenal and placenta

Question 30

What kind of philic is a steroid hormone

Answer 30

lipophilic as it is derived from cholesterol, and diffuse out of the manufacturing cell when they are synthesised

Question 31

Steroid hormones need to be bound by what protein for transport and circulation?

Answer 31

carrier proteins, which helps extend their half life by protecting them from being rapidly metabolised and degraded when they pass through the liver

Question 32

How do steroid hormones elicit effects?

Answer 32

by activating target genes for protein synthesis

Question 33

what are amines?

Answer 33

small size molecules derived from the amino acid tyrosine or tryptophan

Question 34

what are catecholamines?

Answer 34

collective term for a group of tyrosine derived amine hormones like adrenaline, noradrenaline dopamine

Question 35

What differentiates thyroid hormones derivation from other amines?

Answer 35

they are comprised of couples tyrosine resiunes with iodine attached, and this iodination changes its biochemical properties from other classical amines like catecholamines

Question 36

catecholamines are hydro___ whereas thyroid hormones are hydro___

Answer 36

philic (lipophobic) , phobic (lipophilic)

Question 37

Thyroid hormones have a ___ half life of a ___ compared to catecholamines with a half life of ___

Answer 37

longer, few days, few minutes

Question 38

Thyroid hormones interact with _________ and activate ___ whereas catecholamines interact with ____ and activate ________

Answer 38

intraceullar receptors, genes, receptors at cell surface, 2nd messengers