Homeostasis

Question 1

homeostasis

Answer 1

the ability of an organism to maintain a constant internal environment

Question 2

what is the external environment

Answer 2

surrounding environment where an organism is
most organisms bar humans have little to no ability to control their external environment

Question 3

what is the internal environment

Answer 3

surrounding of cells in a multicelled organism
for example in humans this refers to tissue fluid

Question 4

examples of homeostasis in humans

Answer 4

body temp 37C
pH of blood and tissue fluid close to 7.4
preventing build-up of toxic chemicals in the body
maintaining sufficient oxygen levels
regulating the level of glucose in blood plasma so it stays close to 0.1%

Question 5

what disease is associated with regulating the level of glucose in blood?

Answer 5

diabetes- pancreas cannot produce insulin

Question 6

organs + systems involved in homeostasis

Answer 6

skin
kidneys
liver
defence system

Question 7

function of skin

Answer 7

controls body tempurature

Question 8

function of kidneys

Answer 8

controls blood plasma and tissue fluid pH
prevents build up of toxic waste

Question 9

function of liver

Answer 9

prevent build up of toxic waste

Question 10

function of defence system

Answer 10

prevents infection

Question 11

how is diffusion and gas exchange improved in the respiratory system

Answer 11

increased surface area for exchange of gas by diffusion ie alveoli in lungs

Question 12

how is diffusion and gas exchange improved in the excretory system

Answer 12

takes materials waste materials to the body surface ie waste products excreted from human body

Question 13

how is diffusion and gas exchange improved in circulatory system

Answer 13

used to transport materials such as gases, nutrients and toxic waste over long distances

Question 14

transpiration

Answer 14

release of water through stomata

Question 15

how does temperature regulation work in plants?

Answer 15

if a plant is too hot then it will increase transpiration in an effort to cool down

Question 16

endotherms

Answer 16

animals who’s internal temperature remains constant despite environmental temperature changes eg mammals and birds

Question 17

ectotherms

Answer 17

animals who’s internal temperature changes with environmental temperatures
eg lizards insects

Question 18

how does temperature regulation work in endotherms

Answer 18

have a variety of different ways throughout the body but mainly through the skin ie sweating or goose bumps

Question 19

how does temperature regulation work in ectotherms

Answer 19

activity levels depend directly on the temp of their environment. if they need to warm up, they will sit in direct sunlight etc

Question 20

advantage of being endothermic

Answer 20

enzymes stay at optimum temperature, so metabolism is carried out optimally

Question 21

how to endotherms remail at a constant temperature?

Answer 21

metabolism produces lots of heat energy. our bodies have the ability to control the loss of this heat mainly through the skin