Homeostasis

Question 1

name the 4 main tissues in the human body

Answer 1

Muscle
Nervous
Epithelial
Connective

Question 2

name the 6 main organs of the human body

Answer 2

lungs
brain
kidney
heart
stomach
colon

Question 3

name the 10 body systems of the human body

Answer 3

nervous
endocrine
immune
circulatory
muscle and skeletal
integument
respiratory
urinary
digestive
reproductive

Question 4

define the term “Homestasis”

Answer 4

the state of steady internal physical and chemical conditions maintained by living systems, were the body reacts to CHANGE in order to keep conditions inside the body the same.

Question 5

name the 7 factors which are homostatcally regulated

Answer 5

conc of nutrient molecules
con of O2 and C02
conc of waste product
pH
conc of water, salt and electrolytes
temperature
volume and pressure

Question 6

define intracellular fluid

Answer 6

fluid contained within ALL of the cells of the body

Question 7

define extracellular fluid

Answer 7

fluid OUTSIDE the cells of the body and is the internal environment in which the cells live

Question 8

what is the extracellular fluid composed of

Answer 8

plasma and intersticial fluid

Question 9

explain the homestatic controll system

Answer 9

a functionally interconnected network of body components ,operating to maintain a physical or chemical factor in an internal environment

Question 10

define the term intrinsic

Answer 10

inherent compensatory response of an organ to a change

Question 11

define the term extrinsic

Answer 11

response of an organ triggered by factors external to organ (by endocrine glands or nervous system)

Question 12

explain the Negative feedback mechanism

Answer 12

1.change in homestatically controll factor triggers a response
2.this seeks to restore factor to normal by moving factor in the opposite direction of its initial change
3.is a pathway where respond opposes OR removes signal

Question 13

explain the positive feedback mechanism

Answer 13

1.the output is continuously enhanced or amplified
2.this is so the controll variable continues to be moved in the direction of the initial change
3.the pathway in which the initial response reinforces the stimulus

Question 14

explain the feedforward mechanism

Answer 14

brings about a compensatory response in anticipation of a change in a regulated variable

Question 15

Describe a positive feedback mechanism

Answer 15

Child Birth is an example of positive feedback
1.onset of labour
2.oxytocin released from hypothalmus
3.increased uterine contraction
4.babys head pushed through cervix
5.stretch of cervix
6.more oxytocin released
7.increased uterine contraction

Question 16

discuss fall in temperature in negative feedback.

Answer 16

1.thermostat-connecting circuit-furnace-heat

Question 17

discuss fall in blood pressure as negative feedback.

Answer 17

pressure sensors-nerves-heart and blood vessels-increaed blood pressure