Chapter 7 Hormones and Co-ordination

Question 1

what does the nervous system and hormones do

Answer 1

they enable the body to respond to external changes and to control the internal environment

Question 2

why does blood play a central role in homeostasis

Answer 2

it transports materials and distributes heat

Question 3

what are reflex actions

Answer 3

they are rapid automatic responses to stimuli

Question 4

how does a voluntary action start

Answer 4

it starts from impulses from the brain

Question 5

what is the brain a centre for

Answer 5

the brain is a centre for co-ordination with the ability to learn and remember

Question 6

what are the benefits of reflex actions

Answer 6

moving a hand away from a heat source, pupil constricting in bright light

Question 7

what is the difference between reflex actions and voluntary actions

Answer 7

voluntary actions is where your brain thinks about what you want to do, whereas reflex reactions happen automatically to protect the body from danger

Question 8

analyse a reflex action

Answer 8

stimulus - sensory neurone - CNS - motor neurone - effector - response

Question 9

what is a synapse

Answer 9

tiny gaps between the neurones where the electrical impulse stimulates the production of a chemical which diffuses across the gap

Question 10

what is the role of the cornea

Answer 10

transparent and bens light rays towards the lens

Question 11

lens

Answer 11

can change shape to focus light on to the retina

Question 12

ciliary muscles

Answer 12

changes the thickness of the lens when focusing

Question 13

suspensory ligaments

Answer 13

holds the lens in place

Question 14

iris

Answer 14

changes size of pupil to control the amount of light entering the eye

Question 15

how is long sight corrected

Answer 15

converging

Question 16

how is short sight corrected

Answer 16

diverging

Question 17

what is a optometrists

Answer 17

they are scientists who evaluate the ability of the eye to detect light, they can also detect other health problems by observing changes in the eye and testing pressures in the eye

Question 18

type of light in the workplace

Answer 18

reduce accidents, increase productivity
blue enriched light improves alertness and mood
but too much light can damage eyes

Question 19

what are the benefits of corneal transplant

Answer 19

it replaces the damaged layer of cells therefore light can pass onto the retina

Question 20

how do you recongnise reinopathy

Answer 20

this is when blood vessels in the retina are damaged, this is the result of high blood sugar with someone of diabetes and pressure
they can test this by puffing air into the eye to help diagnose this

Question 21

how do you recongnise alzhimers

Answer 21

you can identify a protein in the eye which is usually found in the brian

Question 22

what is the range of frequency audible of the human ear

Answer 22

20-20000 hz

Question 23

what are hormones

Answer 23

hormones are chemicals released by ductless glands into the blood which may affect a target organ or the whole body

Question 24

what is the role of the growth hormone

Answer 24

stimulates growth and cell reproduction

Question 25

what is the role of the thyroxin

Answer 25

controls the metabolic rate

Question 26

what is the role of insulin

Answer 26

causes the liver to absorb glucose and covert is to glycogen when blood sugar levels are high

Question 27

what is the role glucagon

Answer 27

causes the liver to change glycogen to glucose when blood sugar levels are low

Question 28

what is the role of adrenaline

Answer 28

increases blood sugar heart rate and breathing rate

Question 29

what is the role of oestrogen

Answer 29

controls female sexual development

Question 30

what is the role of testosterone

Answer 30

controls development of male sexual characteristics

Question 31

what are endocrinologists

Answer 31

these are scientists who investigate the effect of hormones on the body functioning

Question 32

what are the endocrine glands stimulated by

Answer 32

chemical changes in the blood

Question 33

describe how ADH works

Answer 33

ADH increases the reabsorption of water by the kidneys when the hypothalamus detects that the blood water content is too low

Question 34

how is blood sugar detected

Answer 34

beta cells in the islets have receptors to detect high concentrations of glucose - then insulin is released by the islet cells, when there is a fall in glucose concentration then the beta cells are no longer stimulated and they stop producing insulin. alpha cells in the islet result in glucoagon secretion ....

Question 35

what are the advantages of adrenalin during times of stress

Answer 35

more oxygen and glucose reaches muscles for aerobic respiration therefore more energy released

Question 36

the methods of banting and best

Answer 36

they extracted insulin Banting realised that digestive juices in the pancreas destroying the hormone they decided to tie off the pancreatic duct in healthy dogs, this meant that the cells producing the digestive juices died and the cells that were left the Islet were removed and extracted in to diabetic dogs which healed the dogs

Question 37

the modern methods of treating diabetes

Answer 37

type 1 - pancreas stops producing inuslin, treated with a healthy diet and insulin injections type 2 - develops gradually and the pancreas does not produce enough insulin or the liver and other cells become too insulin resistant - weight control, diet and physical activity, then injections

Question 38

why cant insulin be given in tablet form

Answer 38

because its a protein and would be digested

Question 39

how is body temperature monitored and controlled

Answer 39

by the thermoregulatory centre in the brain which sends nerve impulses to the organs which need to act

Question 40

how does the thermoregulatory centre measure temperature

Answer 40

measures the temperature of blood flowing through the brain | and measures the skin temperature - skin receptors

Question 41

what does sweating do

Answer 41

sweating cools the body, more water is lost when it is hot and has to be consumed

Question 42

if sweating increases

Answer 42

loss of water in urine decreases

Question 43

where is the thermoregulatory centre

Answer 43

it is in the hypothalamus