human physiology and exercise > endocrine system > Flashcards

endocrine system Flashcards

(107 cards)

Study These Flashcards
1
Q

what is the endocrine system? what does it consist of?

A
  • one of the major communication system
  • consists of glands and organs that secrete hormones
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

how many hormones can a single gland secrete?

A
  • multiple
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what are hormones?

A
  • chemical messengers carried by blood to target cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

why are hormones released?

A
  • released by glands to elicit a response
  • enhance/ inhibit cellular reactions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what concentration are hormones present at?

A
  • low concentrations
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

what cell does a hormone effect?

A
  • only affects specific target cells even though a given hormone travels throughout the body in blood
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what do hormones help regulate? (5)

A
  • chemical composition and volume of internal environment e.g. interstitial fluid
  • metabolism and energy balance
  • contraction of smooth and cardiac muscle fibres
  • glandular secretions
  • some immune system activities
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

what do hormones control?

A
  • growth and development
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what are the other two roles of hormones?

A
  • regulate operation of reproductive system
  • helps establish circadian rhythm
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what is the difference between endocrine system and nervous system?

A
  • endocrine involves chemical messengers whereas nervous system involves electrical conduit system
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

what is the time of action and the effects of endocrine system?

A
  • acts relatively more slow
  • often longer lasting effects
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

what is the time of action and the effects of nervous system?

A
  • instantaneous action (within Ms)
  • short lived effect = briefer
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what are the mediator molecules and site of action of endocrine system?

A
  • hormones delivered to tissues throughout body by blood
  • site is far from site of release ; binds to receptors/ target cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are the mediator molecules and site of action of nervous system?

A
  • neurotransmitters released locally in response to nerve impulses
  • close to site of release; at synapse it binds to receptors in postsynaptic
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what are the target cells of endocrine system?

A
  • cells throughout body
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are the target cells of the nervous system?

A
  • muscles (smooth, cardiac or skeletal), cells, glands, other neurons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

what are the three structural classes of hormones?

A
  • amines, peptides/ proteins and steroids
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

what are amines derived from and secreted by?

A
  • derivatives of amino acid tyrosine
  • secreted by adrenal medulla/ hypothalamus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

what are examples of amines?

A
  • thyroid hormones, dopamine, catecholamines
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

what are peptide hormones, are they common?

A
  • polypeptides are most common
  • many peptide hormones are synthesised as large, inactive molecules that are cleaved into active fragments
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

what is an example of a peptide hormone?

A
  • insulin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

what are steroids produced by and where from?

A
  • produced from cholesterol by adrenal cortex and gonads
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

what are examples of steroids?

A
  • aldosterone, cortisol, androgens e.g. testosterone, oestrogens
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

what are peptide and all catecholamine hormones? how do they circulate?

A
  • water soluble
  • circulate dissolved in plasma
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what do some peptide hormones bind to?
- plasma proteins
26
how long does it take peptide hormones and catecholamines to be removed from blood?
- rapid
27
where are receptors for water soluble peptide hormones and catecholamines?
- on plasma membrane
28
what do peptide hormones and catecholamine exert in terms of actions?
- rapid (nongenomic) and slower (gene transcription) on same target cell
29
how long does it take steroid and thyroid hormones to be removed from blood?
- removed more slowly - as they circulate bound to plasma proteins
30
how do steroid and thyroid hormones circulate?
- mainly bound to plasma proteins
31
where are majority of receptors for lipid soluble steroid and thyroid hormones? what do they affect?
- inside target cells - affect cell function by altering gene expression
32
what are the major organs involved in removing hormones from plasma? how do they do this?
- liver and kidney - metabolise or excretes them
33
describe what liver is used for
- major organ responsible for metabolic inactivation (called metabolism or biotransformation)
34
describe what kidneys are used for
- filter blood, remove waste products including hormones+ their metabolites
35
what are some hormones metabolised into?
- more active molecules in their target cells or organs
36
what does responsiveness of a target cell to a hormone depend on? (3)
- hormone's concentration in blood - abundance of target cell's hormone receptors - influences exerted by other hormones
37
what is permissive action? give examples
- action of one hormone enhances the responsiveness or activity of another hormone e.g. epinephrine and thyroid hormones stimulation of lipolysis
38
what is synergistic action? what is an example
- effect of two hormones acting together is greater or more extensive than one hormone acting on its own e.g. follicle- stimulating hormone and estrogens
39
what is antagonistic action? give an example
- one hormone opposes the actions of another hormone e.g. insulin, glucagon
40
what regulates the secretion of many hormones?
- negative feedback systems
41
what are the inputs that control hormone secretion?
- plasma concentration of an ion or nutrient that the hormone regulates - neural input to endocrine cells - other hormones
42
what is an example of plasma concentration of an ion/ nutrient that the hormone regulates?
- insulin secretion
43
describe neural input to endocrine cells ; ANS
- autonomic nervous system controls hormone secretion via adrenal medulla and other endocrine glands
44
what can also secrete hormones?
- neurons in hypothalamus
45
what is a tropic hormone? give an example
- hormone that stimulates the secretion of another hormone e.g. thyroid- stimulating hormone or follicle- stimulating hormone
46
what are the two types of glands in the body?
- exocrine and endocrine
47
what are exocrine glands?
- secrete their products into duct e.g. sweat and intestines
48
what are endocrine glands?
- ductless and release hormones into blood
49
why do disorders of endocrine system vary considerably?
- wide variety of hormones and endocrine glands
50
what is too little hormones referred to as? give an example
- hyposecretion e.g. type 1 diabetes
51
what is too much hormone referred to as? give an example
- hypersecretion e.g. gigantism
52
what is the decreased resposiveness of target cells to hormone know as? what is an example?
- hyporesponsiveness type 2 diabetes
53
what is an increased responsiveness of the target cells to hormone called? give an example
- hyperresponsiveness e.g. elevated heart rate due to increased circulating levels of thyroid hormone
54
what can hormones be used for?
- pharmalogical administration of hormones for medical purposes
55
what can hormones result in?
- supraphysiological concentrations and effects not typically observed with at physiological concentrations
56
what is an example of a medicine containing cortisol?
- corticosteroids are administered to suppress allergens and inflammation
57
what is the risk of experiencing side effects depending on? (4)
- type of steroid ( oral= act systematically so more likely) - does - length of treatment - age of patient (child/ older adults)
58
where are hormones synthesised?
- hypothalamus
59
where do axons pass down and terminate?
- axons pass down infundibulum - terminate in posterior pituitary and release hormones
60
what does the anterior pituitary gland secrete?
- growth hormone, thryoid- stimulating hormone, adrenocorticotropic hormone, prolactin and two gonadotropic hormones- follicle- stimulating hormone and luteinizing hormone
61
what is secretion of anterior pituitary gland controlled by? how are the connected?
- hypophysiotropic hormones from hypothalamus via portal vessels connecting hypothalamus and anterior pituitary gland
62
what does negative feedback do?
- inhibits hormonal response
63
where is the thyroid gland?
- sits within the neck in front of trachea
64
what effects do thyroid hormones have on the body? give an example
- diverse and widespread effect e.g. protein synthesis in follicular epithelial cells, increases DNA replication and cell division
65
what does thyroid gland produce?
- thyroxine ( T4= 4 iodine's) and triiodothyronine (T3)
66
what is the major thyroid hormone ?
- T3 as T4 converted to T3 in target tissues via enzymes
67
what is thyroid- stimulating hormone production controlled by?
- negative feedback action of T3 and T4 on anterior pituitary gland and to lesser extent, the hypothalamus
68
what does TSH cause? what can excessive exposure cause?
- hypertrophy of thyroid tissue - excessive exposure of thyroid gland to TSH can cause goiter
69
what is increased T3 and T4 associated with?
- increased oxidative substrate metabolism and mitochondrial enzyme activity = increased carb and lipid metabolism
70
what is T3 required for? why is it important
- normal production of growth hormone from anterior pituitary gland - important developmental hormone for NS
71
what is cortisol secretion mediated by?
- hypothalamus- anterior pituitary gland system
72
what does cortisol affect in non- stressful situations?
- responsiveness of smooth muscle cells to epinephrine and norepinephrine (permissive) - helps maintain normal blood pressure
73
what does cortisol maintain and what are the other functions?
- maintains enzyme conc. involved in metabolism homeostasis to prevent plasma glucose conc. dropping - anti- inflammatory and anti- immune functions
74
when is cortisol the highest?
- around 9am
75
how is metabolism affected in stressful situations ? (4)
- stimulation of protein catabolism in bone, lymph, muscle - stimulation of liver uptake of amino acids- glucose (gluconeogenesis) - maintenance of plasma glucose conc. - stimulation of triglyceride catabolism in adipose tissue, with release of glycerol and fatty acids into blood
76
what does cortisol enhance in stressful situations?
- enhanced vascular reactivity - improves cardiovascular performance
77
what protective effects does cortisol have?
- unidentified protective effects against damaging influences of stress
78
what does cortisol inhibit in stressful situations?
- inflammation and specific immune responses - nonessential functions e.g. reproduction and growth
79
what do massages decrease?
- circulating cortisol levels
80
how do massages support recovery? (3)
- increased cortisol at rest inhibits immune system - inhibits inflammatory response - decreases capillary permeability in inured areas
81
how is the stress response a combination of endocrine system and nervous system working together?
- sympathetic nervous system is activated, triggering release of epinephrine - at same time, endocrine system releases cortisol from adrenal glands
82
what effects does cortisol have on epinephrine?
- synergistic effect
83
what is the net result of cortisol in stressful situations? (3)
- faster breakdown of fuel stores - larger increase in cardiac function - bigger increase in ventilation
84
what four hormones are most important for human growth?
-growth hormone, insulin- like growth factors 1 and 2 - T3 (childhood/ adolescent) - insulin (fetal life) - testosterone and estradiol
85
what effects do hormones involved in growth have?
- widespread effects
86
what is growth hormone the major stimulus of?
- postnatal growth
87
what does growth hormone stimulate?
- release of IGF-1 from liver and other cells; acts locally to stimulate cell division
88
how else can growth hormones act?
- directly on cells to stimulate protein synthesis
89
when is growth hormone secretion highest?
- during adolescence
90
what is growth hormone secretion stimulated and inhibited by?
- stimulated by growth hormone- releasing hormone (GHRH) - inhibited by somatostatin (SST)
91
where is testosterone produced in males?
- produced by testes
92
where are the small quantities of testosterone in women produced from?
- ovaries and adrenal cortex - peripheral conversion of androgens
93
what does testosterone promote?
- muscle growth - development of male sex characteristics
94
where is oestrogen and progestogen produced from in females?
- produced by ovaries
95
where else can oestrogens be produced from in post- menopausal females?
- produced in smaller amounts by other tissues e.g. liver, pancreas, bone, adrenal glands, skin, brain, breast
96
how is estrogen produced in males?
- when FSH binds to FSH receptors
97
what does oestrogen and progestogen promote?
- development of female sex characteristics - regulates menstrual cycle and adipose tissue growth
98
what do oestrogens also promote?
- endothelia function - protective effects
99
what is DHEA?
- dehydroepiandrosterone
100
where is DHEA and its sulfates (DHEAS) produced from?
- adrenal cortex
101
what are the roles of DHEAS (2)
- precursors for sex hormones e.g. testosterone - affect various systems of body - purported to be anti- ageing
102
when does DHEA production peak?
- at age 20-30 - declines progressively with age
103
how does DHEA increase?
- following low and moderate intensity exercise - doesn't increase in older adults
104
describe oestrogen containing hormone replacement therapy benefits
- maintains muscle mass and prevents fat infiltration into muscle compartment
105
what are exercise and hormone replacement therapy considered?
- counteractive treatments ; age- related changes in muscle phenotype
106
what does testosterone containing hormone replacement therapy help?
- preserves muscle tissue - offset age- related muscle loss rather than cause significant gains
107
what hormones increase post exercise and what does this promote?
- androgens and testosterone - helps promote anabolic processes
human physiology and exercise
flashcards
Decks in class (18)
# Cards
Brainscape helps you reach your goals faster, through stronger study habits.
© 2026 Bold Learning Solutions. Terms and Conditions