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Flashcards in Hormones Deck (20):
0

Controlling heart rate

- brain -> sympathetic nerve -> SAN
- speeds up (ie if co2 conc is high)
- brain -> vagus nerve -> SAN
-slows down

-sped up by adrenaline

1

Treatment for type 1 diabetes

- insulin injections
- ie genetically modified insulin over pig insulin (more effective& ethically correct)
-no cure (stem cell research)
- check blood glucose levels on sensor

2

Treatment for type 2 diabetes

- diet control/ exercise/ weight control
- small meals often
- some have insulin injections

3

Hypoglycaemia

- low blood glucose level
- very tired
- confused
- irrational behaviour

4

Hyperglycaemia

- high blood glucose level
- dry mouth/ thirsty
- confused/ blurred vision
- ketoacidossis
- can be fatal

5

Type 1 diabetes

-incapable of secreting enough insulin
-insulin dependent

6

Type 2 diabetes

- liver/ target cells dont respond to insulin

7

Diabetes

Risk factors - overweight
- lack of exercise
- family history
- asian/ african
( not known for type 2)
Symptoms- tired/ thirsty/ hyperglycaemia/ hypoglycaemia

8

Hormones

- a chemical secreted by an endocrine gland
- brings about a change in an organ/process elsewhere

9

Exocrine

- secreting a substance into a duct
- which carries them to the target cells
- ie saliva

10

Secretion

- the production& release of a useful product from a cell

11

Endocrine

- secretes a hormone straight into the blood plasma

12

Pancreas

- part exocrine- secretion of pancreatic juice into a duct to the small intestine (lipase, amaylase, trypsin)

- part endocrine - the control of blood glucose

13

Adrenaline

- secreted under stress/ fear/ excitement
- from adrenal glands
- travels in the blood to target cells
- ie SAN increases heart rate
- creates changes to the body to prepare for vigorous excercise

14

Low blood glucose levels (problems)

- cells run short of glucose for respiration (ie brain can only respire glucose)
- can cause low water potential, so cells lose water to the blood

15

Low blood glucose (solution)

- alpha cells in the islets of langerhans detect low blood glucose levels
- secrete glucagon
- (beta cells stop)
-binds to cell membranes of hepatocytes
- glycogen to glucose
- gluconeogenisis- from amino acid/ lipds

16

Gluconeogenisis

Creating glucose from amino acids and lipids

17

Blood glucose level too high (solution)

- beta cells in the islets of langerhans detect high blood glucose level and secret insulin
- (alpha cells stop)
- increased rate of muscle& adipose tissue to absorb glucose through transporter proteins
-glucose binds to receptors on hepatocytes
- activates glucokinase the phosphorylates glucos trapping it in the cell
- other ends transform to glycogen

18

Control of insulin secretion

- k+ ions diffuse freely out of the cell (pd -70mv)
-lots of glucose entering the cell and being phosphorylated& metabolised to produce ATP
- k+ channels sensitive so shut
- (pd -30mv)
- ca2+ channels open due to pd & flood in
- ca2+ causes exocytosis of insulin vesicles

19

Adrenaline in liver cells

- binds to receptors on plasma membrane
- activates a g-protein that splits
-combines with adenylcyclase that activates the enzyme that causes atp- cyclic amp
- cyclic amp binds to protein kinase
- activates glycogen phosphorylase kinase
-binds to glycogen phophorylase
= glycogen to glucose = more glucose