Homeostasis

Question 1

what must be removed from cells

Answer 1

waste and carbon dioxide

Question 2

what must be supplied to cells

Answer 2

nutrients and oxygen

Question 3

what is homeostasis

Answer 3

the various physiological arrangements that serve to restore the normal state once it has been disturbed

Question 4

what are the different systems found within the body

Answer 4

• those that interact with the external environment and expend energy
• those that interact with the internal environment and achieve homeostasis
• those that control other systems

Question 5

what are examples of body systems that control other systems within the body

Answer 5

nervous system and endocrine system

Question 6

what are examples of systems that interact with the internal environment and achieve homeostasis

Answer 6

cardiovascular system, respiratory, excretory and alimentary system

Question 7

what are examples of systems that interact with the external environment and expend energy

Answer 7

the nervous, locomotor, and reproductive systems

Question 8

what does the enzyme pepsin do

Answer 8

works in the stomach and breaks down certain components

Question 9

what does trypsin do

Answer 9

works in different areas of the body, working at a neutral pH

Question 10

what are the different conditions for homeostasis

Answer 10

• temperature
• oxygen
• calcium concentrations
• bicarbonate
• carbon dioxide
• pH
• glucose
• blood pressure

Question 11

what are the two systems that are part of the control of homeostasis

Answer 11

the feedback control and negative feedback control

Question 12

what is the shape of a normal distribution curve

Answer 12

bell shape curve

Question 13

describe the process the body goes through when core body temperatuere goes down

Answer 13

• body temperature decreases
• hypothalamus receives this
• muscle response to increase heat production such as less sweating

Question 14

what is the circadium rhythm

Answer 14

the internal process that regulates the sleep cycle

Question 15

what happens to our body temperature during meals

Answer 15

body temperature will increase

Question 16

what is interstitial fluid

Answer 16

fluids between tissues

Question 17

what are the two forms of cellular communication

Answer 17

electrical and chemical communication

Question 18

how does electric transmission work

Answer 18

occurs via gap junction and involves direct contact between cells. the gap junctions allow the flow of a current from cell to cell, there is a rapid transmission in both directions.

Question 19

what are examples of cells that use electrical transmission to communicate

Answer 19

cardiac muscle and some smooth muscle cells

Question 20

what is a syncytium

Answer 20

linked cells that act together as one unit

Question 21

what occurs in chemical transmission

Answer 21

from cell to cell there is a synapse where a chemical transmitter will diffuse across. this is a one way transmission and is most common in the nervous system

Question 22

when does paracrine signalling occur

Answer 22

from one cell to several cells

Question 23

when does endocrine signalling occur

Answer 23

from many cells to many cells

Question 24

what is the sequence of events of chemical communication

Answer 24

• the impulse arrives at a terminal of a presynaptic cell
• transmitter is released from storage vesicles
• transmitter diffuses in synaptic cleft
• transmitter binds to receptor on postsynaptic cell

Question 25

what is an excitatory response

Answer 25

this is when an impulse is generated, and the muscle contracts, and a gland secretes

Question 26

what is an inhibitory response

Answer 26

the cell is switched off

Question 27

what is paracrine communication

Answer 27

when one cell communicates with several cells locally. can be part of a cascade of reactions

Question 28

which cells most often use paracrine communication

Answer 28

defence cells during inflammation

Question 29

what is autocrine communication

Answer 29

this is where chemicals act on cells by releasing it

Question 30

what occurs in endocrine transmission

Answer 30

chemicals are sent to all parts of the body via the bloodstream.

Question 31

what cells will endocrine transmission work on

Answer 31

those with the correct membrane proteins that make them target cells

Question 32

what are nerves and hormones both used for

Answer 32

communication

Question 33

what is neural communication

Answer 33

communication that can either be specific or localised, and are suitable for rapid response. involves involuntary muscle contraction, a sensory system, a salivary gland, and blood pressure

Question 34

how many cells does neural communication affect

Answer 34

many

Question 35

what is hormonal communication

Answer 35

communication that leads to coordinated, body wide actions. it is slow to act but the effect persists

Question 36

what are some examples of body responses related to hormonal communication

Answer 36

- gastrointestinal gland responses - control of metabolism - regulation of the menstrual cycle

Question 37

what are first messengers

Answer 37

chemical transmitters acting on the receptor protein

Question 38

can all first messengers enter the cell

Answer 38

no

Question 39

what are steroid transmitters

Answer 39

lipids that pass through the outer cell membrane that act on receptors in the target cells. the steroid receptor complex acts on dna in the nucleus to initiate protein synthesis. the protein alters the cell function, and the hormones have a delayed function

Question 40

what are peptide transmitters

Answer 40

these are transmitters that cant enter through the cell membrane. they instead bind to plasma membrane receptors and set up a series of reactions controlled by g proteins. then they activate second messenger systems like cyclic amp and calcium ions

Question 41

how are g proteins activated

Answer 41

the transmitter binds to a membrane receptor and activates the g protein. the atp is converted to cyclic by enzyme adenyl cylase (adenylate cyclase)