5.1.4 Hormonal communication Flashcards
(96 cards)
1
Q
what are hormones?
A
a substance secreted by an endocrine gland, it is carried in the blood plasma, to another part of the body
2
Q
what are some examples of hormones?
A
adrenaline and oestrogen
3
Q
what are the different types of gland?
A
-endocrine gland
-exocrine gland
4
Q
what is an endocrine gland?
A
a gland that secretes to the inside
5
Q
what is an example of an endocrine gland?
A
adrenal gland
6
Q
what is an exocrine gland?
A
a gland that secretes substances into a duct
7
Q
what is an example of an exocrine gland?
A
liver
8
Q
describe the action of hormones
A
- secreted from endocrine gland
- transported in blood plasma
- diffuses out of blood
- binds to specific receptors membrane or in cytoplasm of target cells
- once bound hormone stimulates target cell to produce a response
9
Q
what are target cells?
A
target cells are cells that have receptors embedded in the plasma membrane that are complementary in shape to specific hormone molecules- only these cells will respond to the specific hormone
10
Q
what are the different types of hormone?
A
-steroid hormones
-non steroid hormones
11
Q
describe steroid hormone
A
-lipid soluble (pass through plasma membrane)
-bind to steroid hormone receptors in cytoplasm or nucleus forming a hormone receptor complex
-complex acts as a transcription factor either facilitating or inhibiting the transcription of a specific gene
12
Q
describe non steroid hormones
A
-hydrophilic (cannot pass directly through cell membrane)
-bind to specific receptors on plasma membrane of target cell
-binding triggers a cascade reaction mediated by chemicals called secondary messengers
13
Q
describe the makeup of the adrenal glands
A
-capsule
-adrenal cortex
-adrenal medulla
14
Q
describe the capsule in the adrenal glands
A
thin, outer connective tissue
15
Q
describe the adrenal cortex in the adrenal glands
A
outer region, produces essential hormones
16
Q
describe the adrenal medulla in the adrenal glands
A
inner region, produces non essential hormones
17
Q
where are the adrenal glands located?
A
on top of each kidney and made of two distinct parts, surrounded by a capsule
18
Q
what is the size of the adrenal glands?
A
3cm in height and 5cm in length
19
Q
how many adrenal glands are there?
A
two
20
Q
what are mineralocorticoids used for?
A
maintains balance between salt and water concentrations- therefore, it helps to control blood pressure
21
Q
what are some examples of mineralocorticoids?
A
aldosterone
22
Q
what does aldosterone do?
A
helps control blood pressure
23
Q
what are glucocorticoids used for?
A
-regulates metabolism, controls how the body converts fats, proteins and carbohydrates to energy
-regulates blood pressure
-immune response and regulates inflammatory response
24
Q
what are some examples of glucocorticoids?
A
-cortisol= metabolism
-corticosterone= regulates immune response
25
what are androgens used for?
sex hormones- have a small impact but are important in menopause
26
what is the other name of epinephrine?
adrenaline
27
what does adrenaline do?
Increases heart rate; raises blood glucose concentration (glycogen>glucose)
28
what does noradrenaline do?
works with adrenaline to; increase heart rate; widens pupil; widens airways; narrows blood vessels to non-essential organs (therefore, increased blood pressure)
29
what is the role of the cortex?
production of hormone by the cortex is controlled by hormones released from the pituitary gland, three main types are produced: mineralocorticoids, glucocorticoids and androgens
30
what is the role of the medulla?
hormones are released from the medulla when the sympathetic nervous system is stimulated (e.g. during stress)
31
label the glands in the body
*see paper flashcard*
32
what does the pituitary gland do?
growth hormone, ADH
33
what does the pineal gland do?
melatonin, reproductive, development
34
what does the thyroid gland do?
thyroxine (rate of metabolism)
35
what does the thymus do?
thymosin (stimulates production and maturation of white blood cells)
36
what does the pancreas do?
insulin, glucagon
37
what do the testes do?
testosterone
38
what do the ovaries do?
oestrogen
39
what do the adrenal glands do?
adrenaline
40
how is the adrenal cortex controlled?
production of hormones by the adrenal cortex is controlled by hormones released from pituitary glands in the brain
41
what does the adrenal medulla do?
Hormones are released when the sympathetic nervous system is stimulated. This occurs when the body is stressed.
42
what are the different hormones produced by the adrenal gland?
-cortisol
-corticosterone
-aldosterone
-androgens
-adrenaline
-noradrenaline
43
in what part of the adrenal gland is cortisol produced?
cortex
44
what is the function of cortisol?
-involved in regulation of metabolism
-helps regulate blood pressure and cardiovascular function in response to stress
45
in what part of the adrenal gland is corticosterone produced?
cortex
46
in what part of the adrenal gland is aldesterone produced?
cortex
47
in what part of the adrenal gland are androgens produced?
cortex
48
in what part of the adrenal gland is adrenaline produced?
medulla
49
in what part of the adrenal gland is noradrenaline produced?
medulla
50
what is the function of corticosterone?
works with cortisol to regulate immune response and suppress inflammatory reactions
51
what is the function of aldosterone?
helps control blood pressure by maintaining the balance between salt and water concentrations in the blood and bodily fluids
52
what is the function of androgens?
these hormones are converted elsewhere in the body to female hormones (oestrogens) and male hormones (androgens); however, these steroid hormones are produced in much larger amounts by the ovaries (oestrogen) in women and testes (androgen) in men
53
what is the function of adrenaline?
This increases the heart rate by sending blood quickly to the muscles and brain. It also rapidly raises blood glucose concentration levels by converting glycogen to glucose in the liver.
54
what is the function of noradrenaline?
this hormone works with adrenaline in response to stress, producing effects such as increased heart rate, widening of pupils, widening of air passages in the lungs, and narrowing of blood vessels in non-essential organs
55
why do most mammals possess the fight or flight response?
because in a potentially dangerous situation the body automatically triggers a series of physical responses intended to help the animal survive by preparing the body to either run or fight for life
56
how is the fight or flight response coordianted?
*see paper flashcard*
57
describe how the fight or flight response is coordinated
Once a threat is detected by the autonomic nervous system, the hypothalamus communicates via the sympathetic nervous system and the adrenal cortical system. The sympathetic nervous system uses nervous pathways to initiate body reactions whereas the adrenal cortical system uses hormones in the bloodstream . Th combined effect of these two systems result in the fight or flight response.
58
what are some physiological responses to adrenaline?
-pupils dilate
-heart rate and blood pressure increase
-arterioles to digestive system and skin constrict and those to muscles and liver dilate
-ventilation rate and depth increase
-blood glucose levels increase
-metabolic rate increases
-erector pili muscles in skin contract so hairs stand up
-sweat production increases
-endorphins released in brain
59
what is the purpose of pupils dilating?
lets more light into your eyes so you can see more
60
what is the purpose of heart rate and blood pressure increase?
increased circulation of oxygenated and glucose rich blood to working muscles
61
what is the purpose of arterioles to digestive system and skin constrict and those to muscles and liver dilate?
blood gets diverted to working muscles instead and also to liver so it can release more glucose into the blood
62
what is the purpose of ventilation rate and depth increase?
to take in larger volumes of oxygen to be used for respiration
63
what is the purpose of blood glucose levels increase?
to increase the rate of respiration
64
what is the purpose of metabolic rate increases?
increased respiration so more energy available for movement
65
what is the purpose of erector pili muscles in skin contract so hairs stand up?
to appear larger
66
what is the purpose of sweat production increasing?
to cool down as the blood is being redirected from the skin so it can't cool by radiation
67
what is the purpose of endorphins released in brain?
to enable an organism to fight or flight effectively as it prevents them from feeling pain in that moment
68
describe the effect of adrenaline on glycogen in liver cells
Adrenaline triggers the liver cells to undergo glycogenolysis so that glucose is released into the bloodstream. This allows respiration to increase so more energy is available for muscle contraction.
69
explain why adrenaline cannot pass through cell membranes
adrenaline is a non steroid hormone which means it is hydrophilic so cannot pass directly through cell membranes
70
what is the role of adenylyl cyclase?
this triggers the conversion of ATP into cAMP on the inner surface of the cell membrane in the cytoplasm
71
what effect does cAMP have on kinase enzymes?
the increase in cAMP levels activate specific enzymes called protein kinases which phosphorylate, and hence activate other enzymes
72
explain why the action of adrenaline on liver cells is referred to as a cascade effect
because at each stage of the process, the number of molecules involved increases so the process is said to have a cascade effect
73
explain why cAMP is referred to as a second messenger
because it is only activated when the first messenger adrenaline binds to its receptors
74
explain why adrenaline is referred to as a first messenger
it cannot pass through cell membranes but activates other cells
75
why are first and second messengers needed?
when there are non steroid/peptide hormones that can't get into the cell on their own
76
what are first and second messengers?
First messengers bind to receptors but can't enter cells, they send a signal which activates the second messenger inside the cell which carries out the action by releasing a chemical.
77
describe the cascade reaction of adrenaline on liver cells
1. the hormone adrenaline approaches receptor site
2. adrenaline fuses to receptor site, and in doing so activates and enzyme inside the membrane called adenylyl cyclase
3. adenylyl cyclase converts ATP to cyclic AMP, which acts as a second messenger that activates other enzymes that, in turn, convert glycogen to glucose
78
draw a diagram to demonstrate the cascade reaction of adrenaline on liver cells
*see paper flashcard*
79
what type of gland is the pancreas?
it is both an endocrine and exocrine gland
80
how is the pancreas an endocrine gland?
it is a group of cells that are specialised to secrete hormones directly into the blood
81
what is the endocrine tissue in the pancreas made up of?
the islets of Langerhans
82
what is the islet of Langerhans made up of?
-alpha cells
-beta cells
83
what do the alpha cells in the islet of Langerhan do?
secrete glucagon
84
what do the beta cells do in the islet of Langerhan?
secrete insulin (they are larger and there are more of them)
85
how is the pancreas an exocrine gland?
it secretes substances into a duct
86
what is the exocrine tissue in the pancreas made up of?
acini cells
87
what do acini cells do?
they secrete pancreatic juices (alkaline) and digestive enzymes into ducts (then to the duodenum)
88
what are the digestive enzymes that the acini cells in the pancreas excrete?
-amylases
-proteases
-lipases
89
in the acini cells what does amylase do?
break down starch into simple sugars
90
in the acini cells what does proteases do?
break down proteins into amino acids
91
in the acini cells what does lipases so?
break down lipids into fatty acids and glycerol
92
how do you distinguish the islets of Langerhan?
-they are lightly stained
-they are large spherical clusters
-alpha cells are darker than beta cells
93
what do the islets of Langerhan do?
produce and secrete hormones
94
how do you distinguish the pancreatic acini?
-darker stained
-small, berry like clusters
-produce and secrete digestive enzymes
95
how are the organelles of the alpha and beta cells specialised to manufacture and secrete peptide hormones in the pancreas?
it has more ribosomes, RER and golgi apparatus to maximise protein synthesis as hormones are proteins
96
label a diagram showing a section of the pancreas
*see paper flashcard*
