hormones Flashcards
coordination and homeostasis
1
Q
what does glucagon do?
A
converts glycogen to glucose
2
Q
what does insulin do?
A
converts glucose to glycagon
3
Q
where are oestrogen and progesterone produced?
A
ovaries
4
Q
where are FSH and LH produced?
A
pituitary gland
5
Q
what are some secondary sexual characteristics in boys?
A
-voice breaks
-sperm production begins
-growth and development of genitalia
-pubic hair growth
6
Q
what are some secondary sexual characteristics in girls?
A
–menstrual cycle begins
-pelvis broadens in preparation for pregnancy and labour
-armpit and pubic hair growth
7
Q
what gland is progesterone secreted from?
A
ovary(corpus luteum)
8
Q
what is the target organ/tissue for progesterone?
A
pituitary gland and uterus lining
9
Q
what is the effect of progesterone?
A
-inhibits FSH and LH- stops further ovum being matured and released
-thickness of uterus lining maintained
10
Q
what gland is LH secreted from?
A
pituitary gland
11
Q
what is the target organ/tissue for LH?
A
the follicle in the ovary
12
Q
what is the effect of LH?
A
ovulation
13
Q
what gland is FSH secreted from?
A
pituitary gland
14
Q
what is the target organ/tissue for FSH?
A
the ovary
15
Q
what is the effect of FSH?
A
-follicle develops and ovum matures
-maturing follicle releases oestrogen
16
Q
what is the endocrine system?
A
the bodys second coordination system
17
Q
what do glands do?
A
make hormones (chemical messengers)
18
Q
what are hormones?
A
chemical messengers used in the body created by the endocrine system
19
Q
where are hormones carried?
A
in the bloodstream
20
Q
do excrine glands have a duct?
A
yes
21
Q
do endocrine glands have a duct?
A
no
22
Q
what does the pituitary gland contain?
A
neurones linking it to the hypothalamus
22
Q
where is the pituitary gland found?
A
at the base of the brain
23
Q
where is ADH produced?
A
pituitary gland
24
where is the growth hormone produced?
pituitary gland
25
where is glucagon produced?
pancreas
25
where is adrenaline produced?
adrenal gland
25
where is thyroid stimulating hormone produced?
pituitary gland
26
where is thyroxine produced?
thyroid
27
where is insulin produced?
pancreas
28
how do messages move around the body (nervous system)?
nerve impulses- transmitted through nerve cells
29
how do messages move around the body? (endocrine system)
hormones transmitted in the bloodstream (plasma)
29
speed of travel and time for effect to happen (nervous system)?
travel fast and usually have an instant effect
30
speed of travel and time for effect to happen? (endocrine system)
travel more slowly and usually take longer to act
31
effect localised or widespread (nervous system)?
short lived
32
effect localised or widespread (endocrine system)?
usually longer-lasting
33
example of an act of the nervous system?
iris reacting to bright light
34
example of an act of the endocrine system?
controls the blood glucose levels
35
3 ways in which the 2 methods of coordination are similar?
-both begin with a stimulus
-both end in a response
-both go through an effector organ
36
3 ways in which the 2 methods of coordination are similar?
-nervous coordination goes through the CNS
-nervous coordination involves neurones
-nervous coordination goes to the receptor organ after the stimulus -hormonal goes to the gland
37
when is adrenaline secreted?
when you are scared/angry/excited
38
where are the adrenal glands?
on top of your kidneys
39
in order for the body to be prepared for action what do the muscles require?
a good supply of oxygen and glucose
40
effects of adrenaline on the heart?
-beats faster
-heart rate increases
41
how does the heart beat faster and increase its rate?
sends more blood to the muscles-they receive more glucose and oxygen for respiration
42
effect of adrenaline on the lungs?
-breathing rate increases
-breaths become deeper
43
how does breathing rate increase and our breaths become deeper?
taking more oxygen into the blood
44
effect of adrenaline on the arterioles in muscles?
increases blood flow
45
how do the arterioles in the muscles gain an increase in blood flow?
more oxygen and glucose supplied to respiring cells
46
effect of adrenaline on arterioles in the digestive system?
blood flow diverted away
47
why is the blood flow diverted away from the arterioles in the digestive system?
more blood for muscles
48
what is the effect of adrenaline on the liver?
glucose is released from it
49
why is glucose released from the liver?
glycogen is changed into glucose and released into the blood-muscle cells absorb more glucose and use it for respiration
50
effect of adrenaline on eyes?
pupils dilate
51
why do the pupils dilate when adrenaline acts on the eyes?
increased visual sensitivity
52
what happens to the skin hairs when adrenaline acts upon it?
they rise/stand up
53
why do animals skin hairs stand up?
to make the animal look bigger
53
what is the effect of adrenaline on the brain?
mental awareness increases
54
why does your mental awareness increase upon the act of adrenaline?
your reactions are faster
55
what is homeostasis?
the maintaining of a constant environment in the body predominantly in the blood and tissue fluid
56
examples of internal conditions that are controlled?
temperature, water, oxygen, carbon dioxide, blood sugar and pH
57
how is homeostatic control achieved?
using negative feedback
58
what do the control systems do?
they inhibit the original stimulus
59
what does negative feedback mean?
whenever a change occurs in a system, negative feedback causes a corrective mechanism to start which reverses the original change and brings the system back towards the set point (normal)
60
what happens in a positive feedback system?
the output enhances the original stimulus
61
what hormone is responsible for controlling water levels in the blood?
ADH (anti-diuretic hormone)
62
what is the region in the brain that regulates the concentration of blood?
the hypothalamus
63
what does the loss of water mean for the conc of blood?
the conc starts to increase
64
how does the body know the body has lost water?
detected by special cells in the hypothalamus
65
what do the cells in the hypothalamus do? (water LOSS)
the pituitary gland releases more ADH
66
where does ADH travel to? (water LOSS)
in the blood to the kidney
67
does the collecting duct become more or less permeable to water? (water LOSS)
more permeable
68
what does the collecting duct being more permeable mean? (water LOSS)
more water is reabsorbed back into the blood
68
more water being reabsorbed into the blood means what for the urine? (water LOSS)
urine is more concentrated and has less volume and the blood is more dilute
69
what does the gain of water mean for the concentration of water in the blood?
starts to decrease
70
how is this change detected? ( water GAIN)
by special cells in the hypothalamus
71
what do these special cells in the hypothalamus do? (water GAIN)
cause the pituitary gland to release LESS ADH
72
does the collecting duct become more or less permeable to water? (water GAIN)
less permeable
73
what does the collecting duct being less permeable mean for water and urine concentration? ( water GAIN)
-less water reabsorbed into the blood-makes urine more dilute and increases the volume and blood becomes more concentrated
74
what does diuretic mean?
increasing volume of urine- adding water
75
what 5 things can the level of water in the blood plasma depend on?
-external temperature
-amount of exercise
-amount of water
-salt content intake
76
how does external temperature affect the level of water in the blood plasma?
when its hot we sweat more and lose more water making the blood plasma more concentrated
77
how does the amount of exercise we do affect the level of water in our blood plasma?
if we exercise we get hot and then increase our sweating so we lose more water and the blood plasma becomes more concentrated
78
how does the amount of water affect the level of water in our blood plasma?
the more we drink the more we dilute the blood plasma- the kidneys respond by producing more dilute urine to get rid of the excess water
79
how does your salt content affect the water level in your blood plasma?
salt makes the plasma more concentrated and so it makes us thirsty- we drink more water until the excess salt has been excreted by the kidneys
80
how do drugs affect the water level in your blood plasma?
drugs cause the kidneys to produce a smaller volume of less dilute urine- can result in the body having too much water
81
how does alcohol affect the bodys water level in your blood plasma?
causes the kidneys to produce a greater volume of more dilute urine- can lead to dehydration
82
what is glucose stored as in humans and where?
stored in the liver as glycogen which is a large insoluble polysaccharide
83
what happens when the body is short of glucose?
the glycogen can be broken down into glucose and passed into the bloodstream
84
the role of insulin and glucagon?
insulin-lowers blood glucose
glucagon-raises blood glucose
85
what can increase your blood glucose?
eating a meal
86
what can decrease your blood glucose?
exercise
87
what is type 1 diabetes?
bodys immune system attacks and destroys cells that produce the insulin
88
what is type 2 diabetes?
body doesnt produce enough insulin or the bodys cells dont react to insulin properly
89
1st step when you do vigorous exercise?
blood sugar level falls
90
2nd step of doing vigorous exercise?
cells in pancreas signal to make/release glucagon
91
3rd step of doing vigorous exercise?
glucagon tells the liver to convert glycogen to glucose
92
4th step of doing vigorous exercise?
glucose is released into the blood
93
5th step of doing vigorous exercise?
blood sugar levels back to normal again
94
6th step of doing vigorous exercise?
muscles use up glucose in respiration
95
what is the stimulus for thermoregulation?
change in environmental temperature
96
temperature receptors do what?
send electrical impulses to the hypothalamus
97
what do the temperature receptors stimulate our brains to do?
find shade, have a cool drink, take off a layer of clothing
98
what does the thermoregulatory centre in the hypothalamus do?
detects a change in the temperature of the blood flowing through it (core temperatures)
99
what does homeothermic mean?
warm-blooded
100
what happens when the thermoregulatory centre in the hypothalamus detects a change in the temperature of the blood flowing through it?
this sends a signal via nerves to other organs in the body which then regulate the temperature by physiological nerves
101
what does poikilothermic mean?
cold-blooded
102
does body temperature fluctuate in homeothermic organisms?
stays constant
103
does body temperature fluctuate in poikilothermic organisms?
yes
104
why is homeostasis important for organisms?
it ensures the maintenance of optimal conditions enzyme activity and cell function
105
what is the link between the stimulus and the receptor made by?
the nervous or endocrine system
106
what is homeostasis?
the control or regulation of the internal conditions of a cell or organism
107
what are 2 examples of homeostasis in humans?
- the control of body temperature
- the control of body water content
108
what is body temperature monitored and controlled by?
the thermoregulatory centre in the base of the brain
109
what does the thermoregulatory centre contain?
receptors that are sensitive to the temperature of the blood
110
what does the skin also contain?
temperature receptors
111
what does the skin send impulses to and what kind?
nervous impulses to the thermoregulatory centre
112
what is a coordination centre?
receives and processes information from receptors such as the brain, spinal cord & pancreas
