Introduction to Endocrine Systems

Question 1

why can some diseases look different depending on the patient

Answer 1

the time in the patients life when it manifests as well as the patients own response can impact how the disease appears phenotypically. eg childhood versus adulthood manifestation

Question 2

what is diastema

Answer 2

gaps between the teeth

Question 3

breakdown the key steps of endocrine secretion

Answer 3

chemical secreted at low concentrations into the bloodstream by a cell or a group of cells
it is sent to all parts of the body via the bloodstream
it only acts on cells with the correct membrane receptor protein that targets cells

Question 4

what are the key features of an endocrine secretion

Answer 4

it acts on many places at the same time
it is affected by the strength of circulation
stopping hormonal response requires removal of the hormone from circulation

Question 5

what is the concentration unit of hormones

Answer 5

femtomoles

Question 6

describe humoral communication

Answer 6

communication by hormones on many different cells in the body
coordinated, body wide actions
it is slow to act and the effect persists

Question 7

what are the two main classifications of hormoens

Answer 7

steroids and non steroids

Question 8

what are the non steroid hormone sub categories

Answer 8

amino acid derivatives
peptides
glycoproteins

Question 9

which kind of hormone can enter the cell and why

Answer 9

steroid hormones as they have a lipophilic ring that can penetrate the membrane

Question 10

what are the steroid hormones

Answer 10

cortisol
aldosterone
testosterone
oestrogen
progesterone

Question 11

what are the amino acid derivatives

Answer 11

amines and iodinated amino acids

Question 12

describe some hormones that are amines

Answer 12

adrenaline
noradrenaline
melatonin

Question 13

describe some hormones that are iodinated amino acids

Answer 13

triiodothyronine
tetraiodothyronine (thyroxine)

Question 14

what are the two classifications for peptide non steroid hormones

Answer 14

short chain and long chain

Question 15

what are the short chain peptide hormones

Answer 15

antidiuretic hormone
oxytocin
melanocyte stimulating hormone
somatostatin
thyrotropin releasing hormone
gonadotropin releasing hormone
atrial natriuretic hormone

Question 16

name the long chain peptide hormones

Answer 16

growth hormone
prolactin
parathyroid hormone
calcitonin
adrenocorticotropic hormone
insulin
glucagon
gi tract hormones

Question 17

describe how hormones are produced

Answer 17

many are made in an inactive form first
pre-prohomrones become prohormones in the endoplasmic reticulum
the prohormone is packaged in golgi apparatus and is converted to the active hormone here
the active hormone is then secreted from vesicles

Question 18

describe the insulin structure

Answer 18

complex structure that takes time to be made and therefore must be stored

Question 19

can prohormones generate responses

Answer 19

yes, although they are much less potent as their activated form

Question 20

why is high insulin concentration fatal

Answer 20

can lead to hypoglycemia of the brain
the brain needs glucose to survive, so without it there is death

Question 21

what is a high concentration of prohormones in the blood associated with

Answer 21

high release of their activated hormones

Question 22

what are glycoproteins

Answer 22

proteins with attached carbohydrate groups to the amino acid

Question 23

what are some glycoprotein hormones

Answer 23

follicle stimualting hormone
luteinizing hormone
thyroid stimulating hormone
chorionic gonadotrophoin

Question 24

what are some local tissue hormones

Answer 24

prostoglandins
leukotrienes
thromboxanes

Question 25

what are the functions of local tissue hormones

Answer 25

blood flow regulation haemostasis mucosal protection in the stomach inflammation

Question 26

why are local tissue hormones not really hormones

Answer 26

they are not released into the circulation

Question 27

how do most non steroid hormones bring about responses in cells

Answer 27

via second messenger systems within the target cells the steroid hormones cna pass through the outer cell membrane and directly reach the intracellular receptors

Question 28

what are the two common second messengers

Answer 28

cAMP and Ca++

Question 29

what is the pathway of hormone secretion

Answer 29

endocrine cells are stimulated to produce the hormone into the bloodstream (some need carrier proteins in order to move through the bloodstream) the hormones work on the target cell some are excreted throguh the kidneys and some are metabolised by the liver metabolism produces raw materials that can be recycled for new production cycles

Question 30

how do steroid hormones bring about responses

Answer 30

they pass the membrane and work on the cell machinery to produce a protein direct action will take time as the proteins are being produced

Question 31

can a patient be on cortisol and still have surgery

Answer 31

it is risky and surgeons to ask the gp to take the patient of cortisol for the surgery to make it safer

Question 32

what is negative feedback

Answer 32

a normal biological response that slows or stops a reaction when it reaches a certain level

Question 33

give an example of a negative feedback loop

Answer 33

The parathyroid hormone will raise plasma calcium concentration and inhibit the release of parathyroid hormone. This is a negative feedback loop.

Question 34

what is receptor regulation

Answer 34

the sensitivity of target cells is related to the number of membrane receptors more receptors gives upregulation and less receptors gives downregulation

Question 35

describe upregulation

Answer 35

there are more receptors so there is a higher chance the hormone will bind

Question 36

describe downregulation

Answer 36

there are less receptors so there is reduced chance of binding

Question 37

what can lead to hyperfunction

Answer 37

excess production and secretion upregulation of receptors failure to metabolise a hormone

Question 38

what can lead to hypofunction

Answer 38

decreased production and secretion downregulation of receptors receptors not functioning