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Flashcards in 14- homeostasis Deck (19)
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1

homeostasis

the maintenance of a constant
internal environment for the
organism to stay healthy.

2

warm blooded

-They maintain a constant body temperature despite
external environment changes. (mammals, birds)
-have mechanisms to lose / gain heat when too
hot or too cold.

3

when does negative feedback occur

when conditions change from the ideal or set point and returns conditions to this set point

4

hypothalamus

a part of the brain that acts like a thermostat detecting temperature of the blood going through it.

5

what does the hypothalamus do after it detects a change in heat

-changes are detected by receptors and sent as impulses to the brain through sensory neurons
-reflex action sends electrical impulses, along motor neurons, to effectors to regulate the temp

6

shivering

muscles contract and relax, to produce heat and warm body

7

vasoconstriction

arterioles near the skin become narrower so less blood can flow through them to conserve heat

8

other things that happen in the body to save and produce heat

- metabolism increases to release energy
- goosebumps

9

how are goosebumps produced

erector muscle contracts causing the hair to stand up

10

sweating

droplets of sweat evaporate, cooling the body

11

vasodilation

arterioles near the skin become wider so more blood can flow to loose heat

12

how do goosebumps help conserve heat

when the erector muscles are contracted, they stand up trapping air which is a great insulator

13

how are blood glucose levels controlled

by a negative feedback mechanism involving the production of two hormones (insulin and glucagon-made in pancereas)

14

when is insulin produced in body

when blood glucose rises
- goes to liver converts glucose in blood to stored glycogen

15

when in glucagon produced in body

when blood glucose falls
-goes to liver converts stored glycogen to glucose to be passed into the blood

16

glucagon vs glycogen

glucagon- hormone regulating glucose level in blood
glycogen- polysaccride glucose is stored as (starch in animals)

17

type 1 diabetes

a condition where the blood glucose levels are not able to be regulated as the insulin-secreting cells in the pancreas are not able to produce insulin
- glucose too high

18

how can type 1 diabetes be treated

injecting insulin, diet, monitoring sugar level

19

symptoms of diabetes

increased thirst, urination, hunger, weakness, weight loss, nausea, blurred vision