Homeostasis (ch 7)

Question 1

what is meant by homeostasis

Answer 1

the process where automatic control systems like the nervous system and hormones maintain a constant internal environment

Question 2

what do receptor cells do

Answer 2

detect stimili (changes in the environment) theb send it to coordination centers then coordination centers send information to the effectors which make changes

Question 3

how is carbon dioxide produced

Answer 3

as a product of respiration

Question 4

how is carbon dioxide removed

Answer 4

through the lungs (breathing out)

Question 5

what happens if carbon dioxide isnt removed properly

Answer 5

buildup of carbon dioxide can become acidic and cause your enzymes to denature

Question 6

whats the test for carbon dioxide

Answer 6

limewater turns cloudy

Question 7

whats the test for water

Answer 7

anhydrous copper sulfate turns blue

Question 8

what is deamination

Answer 8

when excess protien gets broken down by the liver to amino acids then ammonia then urea to be filtered by the kindeys and excreted through the bladder

Question 9

where is urea created

Answer 9

the liver

Question 10

whatre the 3 functions of the liver

Answer 10

• deaminate excess amino acids to form urea
• detoxify poisoning substances like ethanol in alcohol
  -breakdown old red blood cells to store iron

Question 11

whatre the 4 glands in the endocrine system

Answer 11

Pituitary gland
adrenal glands
pancreas
thyroid glands

Question 12

whatre hormones

Answer 12

chemicals secreted by endocrine glands into the bloodstream then travel to target organs

Question 13

what do hormones do and how do they act

Answer 13

they regulate the functions of organs and cells, they act quickly but have long lasting effects

Question 14

whatre the 4 internal conditions that have to stay constant

Answer 14

• water content
• blood glucose levels
• ion content
• temperature

Question 15

where is the anti diuretic hormone secreted

Answer 15

Pituitary gland

Question 16

what does ADH control

Answer 16

the amount of water reabsorbed by kidneys

Question 17

where does blood get filtered

Answer 17

kidneys (specifically nephrons)

Question 18

how does water leave the body

Answer 18

when we breathe out, sweat and urinate

Question 19

how do ions and urea leave the body

Answer 19

sweat and the rest gets filtered out of the blood by kidney then sent to urethra in bladder to be excreted

Question 20

what molecule gets fully reabsorbed in the kidneys

Answer 20

glucose

Question 21

what 2 molecules undergo selective reabsorption in the kidneys

Answer 21

ions and water

Question 22

why cant molecules like cells and proteins be filtered through nephrons

Answer 22

its too large to fit through the glomerulus

Question 23

what happens to excess ions water and urea

Answer 23

they go to the urea to get excreted by the bladder

Question 24

whats the process that healthy kidneys undergo

Answer 24

1- blood is filtered through the nephrons
2- all glucose is reabsorbed
3- ions and excess water go through selective reabsorption
4- waste is sent to the bladder to be removed as urine through the urethra

Question 25

what happens when your water content is too high

Answer 25

• piutiary gland will secrete less adh to make the kidney reabsorb less water so you end up with more dilute urine

Question 26

what happens when youre dehydrated

Answer 26

the pituitary gland secretes more adh which allows your kidneys to reabsorb more water so you end up with more concentrated urine

Question 27

how does kidney damage occur

Answer 27

through accidents or genetics

Question 28

whatre the 2 treatments for kidney failure

Answer 28

• dialysis
• kidney transplants

Question 29

what happens in kidney transplants

Answer 29

the damaged kidney is replaced by a healthy one from a donor.
- overall cheaper than dialysis cause patient doesnt need to go to hospitals as often
- you need to take immunosuppressants to avoid your antibodies attacking the donor organ
- immunosuppressants can decrease immunity and cause patuent to be at risk of other diseases

Question 30

what happens in dialysis

Answer 30

• function of kidneys is carried out using a partially permeable membrane
• blood thinner added then blood goes into dialysis machine. dialysis fluid has the same concentration of ions and glucose as healthy blood.
• done 3 times a week and process takes 3-4 hours
• only temporary till a donor organ is found
  issues ; blood clots tts forming, strict diet and very time consuming.

Question 31

what 2 hormones does the pancreas secrete

Answer 31

glucagon which increases glucose levels and insulin which lowers it

Question 32

whats the function of insulin

Answer 32

• allows glucose to move into cells faster and sends glucose to liver and muscle cells to be converted into glycogen for storage this overall decreases blood glucose levels

Question 33

what happens if glycogen stores are full

Answer 33

glucose is broken down and converted into lipids and fats

Question 34

whats the function of glucagon

Answer 34

it causes glycogen stores in the liver and muscles to be broken down into glucose

Question 35

how is type 1 diabetes treated

Answer 35

insulin injections (intravenous so they enter the bloodstream directly), a controlled diet with minimum carbohydrate intake and regular exercise

Question 35

what is type 1 diabetes

Answer 35

usually genetic and starts from younger ages, lifelong condition where your pancreas doesnt produce enough insulin so as a result your cells dont respire which makes you feel tired. as a result you break down protien and fats to use as fuel which results in weight loss

Question 36

what is type 2 diabetes and what is it caused by

Answer 36

• where your body cells dont respond to the insulin made by your own pancreas, caused by obesity and minimal exercise

Question 37

how is type 2 diabetes treated

Answer 37

• balanced diet, loosing weight and exercise
  if this doesnt work drugs can be given to reduce glucose absroption and help cells respond to insulin more effectively

Question 38

what center in the brain regulates body temperature

Answer 38

thermoregulatory center in the hypothalamus

Question 39

what is the optimum internal body temperature

Answer 39

37 degrees , if its too high enzymes will denature and if its too low enzymes will slow down their activity

Question 40

how does the hypothalamus regulate the internal body temperature

Answer 40

it acts as a thermometer and measures any changes in the blood flowing through the brain. skin receptors are also sensitive to temperature changes and send stimuli (signals) to the thermoregulatory center

Question 41

what is vasodilation

Answer 41

when the blood vessles that supply blood to the skin capillaries dilate which allow more blood flow

Question 42

what is vasoconstriction

Answer 42

when the blood vessles that supply blood to skin capillaries constrict so less blood flows near the skin

Question 43

what happens when your internal body temperature rises

Answer 43

a signal is sent to the thermoregulatory center in the brain which sends a signal to the blood vessles that supply blood to your skin capillaries to dilate which increases blood flow (vasodilation). you also sweat which causes water to evaporate off your skin and release heat energy to the environment

Question 44

why is it harder for your core body temp to cool down when its humid

Answer 44

the sweat from your skin takes longer to evaporate since theres lots of water particles in the air which decreases diffusion rates

Question 45

what happens when your internal body temperature falls

Answer 45

a signal is sent to the thermoregulatory center in the brain which sends a signal to the blood vessles that supply blood to your skin capillaries to constrict which decreases blood flow (vasoconstriction). you also shiver and the rapid contraction and relaxation of your muscles causes them to respire and respiration releases heat energy as a waste product which is then passed onto your tissues.