Hormonal Communication

Question 1

endocrine system

Answer 1

a communication system using hormones as signalling molecules

Question 2

hormones

Answer 2

proteins or steroid molecules that are released by endocrine glands into blood and they act as messengers carrying the signal to the specific target organ/tissue

Question 3

target cells

Answer 3

for non-steroid hormones cells that posses a specific receptor on their membrane- shape is complementary to the hormone

Question 4

adrenal cortex

Answer 4

outer layer of the adrenal gland

Question 5

adrenal gland

Answer 5

one of a pair of glands lying above the kidneys which release adrenaline and other hormones (corticoids)

Question 6

adrenaline

Answer 6

hormone which stimulates the body to prepare for fight or flight

Question 7

adrenal medulla

Answer 7

inner layer of the adrenal gland

Question 8

beta cells

Answer 8

found in the islets of Langerhans that secrete insulin

Question 9

glucagon

Answer 9

hormone that causes an increase in blood glucose concentration

Question 10

insulin

Answer 10

hormone released from the pancreas that causes blood glucose levels to go down

Question 11

diabetes mellitus

Answer 11

condition which blood glucose levels can’t be controlled effectively

Question 12

stem cells

Answer 12

unspecialised cells that have the potential to develop into any type of cell

Question 13

types of hormones

Answer 13

protein and peptide hormones (derivatives of amino acids)- not soluble
steroid hormones- soluble so enter nucleus and have direct effect

Question 14

endocrine glands

Answer 14

ductless glands that consist of a group of cells that manufacture and release a hormone directly via capillaries into the blood

Question 15

endocrine organs

Answer 15

pituitary gland, thryoid gland, thymus, adrenal glands, pancreas, ovaries, testes

Question 16

how do target cells work

Answer 16

for non-steroid hormones, must possess a specific receptor complementary to the shape of the hormone to initiate changes in the cell
each hormone is different so only the target cells with specific receptor will respond

Question 17

how are target cells distributed

Answer 17

when receiving an endocrine signal, either grouped together in a target tissue or widely dispersed in a number of tissues

Question 18

first messenger

Answer 18

non-steroid hormones, signalling molecules outside the cell that bind to the membrane and initiate an effect inside the cell

Question 19

second messenger

Answer 19

first causes the release of another signalling molecule in the cell, stimulating a change in the activity of the cell

Question 20

roles of the pancreas

Answer 20

digestion- secretes digestive enzymes

metabolism- regulation of carbs, lipids etc., produces primary messengers

Question 21

2 main secretions of the pancreas

Answer 21

pancreatic juices containing enzymes secreted into the s. intestine
hormones secreted from islets of Langerhans into the blood

Question 22

what enzymes does fluid from the pancreatic duct contain

Answer 22

pancreatic amylase, trypsinogen, lipase, sodium hydrogencarbonate to make it more alkaline

Question 23

endocrine tissues

Answer 23

islets of Langerhans contains alpha and beta cells

Question 24

alpha cells

Answer 24

secrete glucagon to raise glucose concentration

Question 25

beta cells

Answer 25

secrete insulin to lower glucose concentration

Question 26

glycogenesis

Answer 26

glucose converted to glycogen

Question 27

glycogenolysis

Answer 27

glycogen converted to glucose

Question 28

gluconeogenesis

Answer 28

breaking down of triglycerides and proteins

Question 29

glycosuria

Answer 29

glucose in the urine

Question 30

glucose levels must be constant (4-6mmol dm3) because

Answer 30

respiration is a continuous process in all living cells

high concentration of glucose affects the water potential of the blood plasma

Question 31

hypoglycaemia

Answer 31

inadequate delivery of glucose to tissues and brain causing tiredness, irritability, even seizures, unconsciousness, death

Question 32

hyperglycaemia

Answer 32

glucose concentration rises too high for long periods causing organ damage, osmotic water loss, damages blood vessels

Question 33

how do hormones act on hepatocytes

Answer 33

when there is excess glucose, it is converted to glycogen and when glucose is needed it is converted back

Question 34

hepatocytes

Answer 34

liver cells that can store glycogen

Question 35

if blood glucose concentration rises too high

Answer 35

it is detected by beta cells, secrete insulin into the blood, travels through the body to target cells

Question 36

insulin

Answer 36

a small protein and hormone of 51 a.a.

Question 37

how do liver cells release glucose from glycogen

Answer 37

have a specific membrane receptor, insulin binds and causes glucose channels to merge with the membrane

Question 38

if blood glucose concentration drops too low

Answer 38

detected by alpha cells, secrete glucagon into the blood to act on target cells

Question 39

why is glucose concentration controlled by negative feedback

Answer 39

insulin and glucagon are antagonistic but fluctuate around the required concentration

Question 40

glucagon

Answer 40

a small protein hormone containing 29 a.a.

Question 41

diabetes mellitus

Answer 41

a condition in which the body is no longer able to produce sufficient insulin to control its blood glucose concentration

Question 42

other names for type 1 diabetes

Answer 42

insulin-dependent or juvenile-onset diabetes because it starts in childhood

Question 43

other names for type 2 diabetes

Answer 43

non-insulin-dependent diabetes