Homeostasis and thermoregulation

Question 1

what is homeostasis?

Answer 1

the body’s abbility/atempt to adjust to flucuating enviroments (external)

Question 2

homeostasis invloves the interactions of several______, which are…

Answer 2

systems: endocrine, nervous, excretory, ect.

Question 3

common examples of everyday homeostasis

Answer 3

skin sweats to reduce heat, kidneys maintain water balance, pancrease regulates blood sugar, skeletal muscles contract to generate heat (shivering)

Question 4

Homeostatic control systems

Answer 4

the Monitors- sense based organs
the Coordinating center- brainnervous system
the Regulator- action/fix

Question 5

Negative feedback

Answer 5

counter-act the variable (proper response)

mechanisms that make adjustments to bring the body back within an acceptable range

Question 6

postive feedback

Answer 6

compounds the problem- intensify the variable

move the controlled variable away from normalcy
eg. the process of birth (hormones+contractions)

Question 7

thermoregulation

Answer 7

maintaining the body temp withina range that enables cells to function effeciently (to hot could denature the protein within the cell)

Question 8

Ectotherms

Answer 8

Invertibrates (most fish, amphibians and reptiles)

depend on air/external temp to regulate metabolic rates

Question 9

Endotherms

Answer 9

Mammals and birds
- able to maintain a constant body temp regardless of external factors (to a certain point)
e.g- when there is a decrease in temp the rate of cellular respiration speeds up to generate heat

• different parts of the body may have different regulatory temps (testies)

Question 10

what is the optimal temp for humans

Answer 10

37 degrees celsius

Question 11

when does the temperatures fall in most individuals

Answer 11

during the night

Question 12

response to heat stress

Answer 12

sensors in the brain ditect a rise in body temp
- a nerve message is coordinated within the hypothalamus and sent to the sweat glands
- once the sweating starts the evaportaion off the skin will cause cooling
- at the same time your blood vessels will dialate within the skin allowing heat to escape-cooling down the blood

Question 13

term for above temp

Answer 13

hyperthermia

Question 14

term for below temp

Answer 14

hypothermia

Question 15

response to cold stress

Answer 15

when the external temp drops thermoreceptors in the skin send a message to the hypothalamus

the hypathalamus tells the organs to increase body temp

at the same time nerves goin to the artiroles of the skin cause smooth muscle to contract and arteriols to constrict limiting blood flow and reducing heat loss

Question 16

goosebumps

Answer 16

• response to cold stress or your fight or fight response

when goosebumps form the errect hair ratains body heat

Question 17

response to prolonged exposure to the cold

Answer 17

can cause a hormonal reaction that elevates metabolism

Question 18

brown fat

Answer 18

capable of turning chemical energy into heat

Question 19

when is brown fat important/essential

Answer 19

in inffants because they lack the ability to shiver
- found in the armpits, neck, and kidneys to insulate and generate heat

Question 20

what happens when cells freeze

Answer 20

cytoplasm forms ice crystals, which act as microscopic knives peircing and slashing their way through the cell membrane

Question 21

is it bad when there are holes in the cell membrane

Answer 21

yes this causes important nutrients and cell organelles to leak out, causing the cell to collapse resulting in damage to the larger organs

bloodvesels rupture and nerves are crushed