Endocrine System Flashcards
1
Q
What are hormones?
A
Signaling molecules that are secreted into extracellular fluid, circulate in the bloodstream and communicate regulatory messages through the body
2
Q
Hormones affect on all cells
True or false?
A
False
Hormones act only on cells with its specific receptors.
Cells lacking receptors for that hormone are not affected
3
Q
What are two major systems for communication and regulation in body?
A
Endocrine system-Chemical signaling by Hormones
Nervous system
Neurons—>signals—->regulate muscle,neurons and endocrine cells
4
Q
Intercellular communication is classified by _____ and ______
A
Types of secreting cells - the route taken by signal
5
Q
What is endocrine signaling?
A
Hormones are secreted into extracellular fluid by endocrine cells and reach target organs via bloodstream.
6
Q
Major function of endocrine signaling
A
To maintain HOMEOSTASIS
7
Q
What is Paracrine signaling?
A
Local regulators acts on target cells that lie near the secreting cells
8
Q
What is autocrine signaling?
A
Local regulators acts on secreting cells themselves are target cells.
9
Q
______are used in both paracrine and autocrine
A
Local regulators-molecules that act over short distances,reach their target cells by only diffusion
10
Q
Types of local regulators
A
Prostaglandins-modified fatty acids
Cytokines-Polypeptides
Growth Factor-promote cell growth,division and development
Nitric oxide-gas which acts as neurotransmitter and local regulator
11
Q
What is synaptic signaling?
A
Neurons communicate with target cells(i.e.neurons,muscle cells or glands) via specialized junctions called the synapses .
Most synapses,neurons secrete neurotransmitters which diffuse and binds to target cells
12
Q
Synaptic signaling is important for ____
A
Sensation
memory
Cognition
Movement
13
Q
What is neuroendocrine signaling?
A
Neurons called neurosecretory cells secrete neurohormones,which diffuse from nerve cells ending to the bloodstream
Eg.Antidiuretic hormone (ADH)-in kidney function and water balance
14
Q
Do all secreted signaling molecules act within the body?
A
No
15
Q
What are Pheromones?
A
Signaling molecules of certain animals that released into the external environment.
Eg.For attracting mates
16
Q
NO acts as both______ and _____
A
Local regulator - Neurotransmitter
17
Q
No action in vasodilation
A
When the level of O2 falls in blood,epithelial cells in blood vessel walls synthesize and release NO.after diffusing into surrounding smooth muscles of blood vessels, NO activates an enzyme that relax the cells leading to vasodilation
human male—->Vasodilation effect of NO promotes erection
18
Q
Major classes of Hormones
A
1)Polypeptide-insulin
2)Steroids-cortisol(all derived from cholesterol)
3)Amines-epinephrine and thyroxine
19
Q
Epinephrine,norepinephrine and thyroxine are synthesized from an amino acid ______ or _____
A
tyrosine - tryptophan
20
Q
Water soluble hormones
A
polypeptide hormones and most amine hormones
21
Q
Lipid soluble hormones
A
Steroid hormones and non polar hormones(i.e.Thyroxine)
Thyroxineကamine hormoneပေမဲ့lipid soluble
22
Q
Water soluble hormones are secreted by _____ and travel ____ in bloodstream
A
exocytosis
freely
23
Q
Do water soluble hormones can diffuse through the plasma membrane?
A
No
24
Q
Water soluble hormones binds to ______ receptors
A
cell surface
25
Water soluble hormone’s functions
changes in cytoplasmic molecules and sometimes altering gene transcription
Cellular responses တွေဖြစ်(activation of enzyme,uptake or secretion of molecules,rearrangement of cytoskeleton)
26
Lipid soluble hormones exit the cells by____
Diffusion and binds to transport proteins
water insoluble မလို့bloodထဲမှာသွားတဲ့အခါtransport proteinလို
27
Lipid soluble hormones binds to____
receptor in cytoplasm or nucleus
28
Lipid soluble hormones’s function
changes in gene transcription
29
What is signal transduction?
chain of events thet converts the extracellular signal to a specific intracellular response
cellအပြင်မှာပေါင်းပေးမဲ့အထဲမှာresponseပေး
30
Example of signal tranduction
Epinephrine aka adrenaline
Epinephrine binds to G protein-coupled receptor on membrane which triggers synthesis of cAMP.
cAMP activates protein kinase.
Kinase then activates enzymes for glycogen breakdown and inactivates enzymes fir glycogen synthesis
31
Most steroid hormones are located_____
in the cytosol
32
Binding of steroid hormone to receptor
when steroid hormone binds to receptors, it forms hormone-receptor complex and then moves to nucleus
eg.Estrogen,estradiol
33
All lipid soluble hormones’s receptors are in cytosol. True or false?
false
Thyroxine,Vitamin D and other lipid soluble hormones’ receptors are in nucleus
34
What are hormones?
Signaling molecules that regulate the physiological processes in our bodies
Eg, maturation hormones- sexual maturation and distinct sexual dimorphism between adult males and females
35
A hormone can travel throughout the body. Can it affect every cell?
No, only some cells have the receptors for that hormone. Cells lacking a receptor for that hormone are unaffected
36
What are the two major control and regulating system in our body?
Nervous system and endocrine systems
Neurons——>signals——> regulate muscle, neurons , and endocrine cells.
37
Endocrine signaling regulates —— and mediate responses to —— and —— and ——
Regulate HOMEOSTASIS
Mediate properties including blood pressure and volume, environmental stimuli, growth and development, maturity and reproductiion
38
Paracrine and autocrine use———
Local regulators
Eg- prostaglandins- pain and inflammation to the injury
Prostaglandins blockers- aspirins, ibuprofens - anti pain and anti inflammatory
Prostaglandins is also involved in regulation of platelets
Prostaglandins are made of fatty acids
39
What is synaptic signaling?
Neurons communicate with other neurons or muscle via specialized junctions called synapses, at synapses, neurons secrete neurotransmitters, which diffuse very short distances
40
What is neuroendocrine signaling?
Neurons secrete hormones called neurohormones, which enter the blood stream .
41
What are pheromones?
Members of some animal species use PHEROMONES to communicate with each other. Not all signaling molecules act on the body. Some are released into the external environment.
For example, ants use pheromones to mark the track of the food source
42
Cytokines are —— and they function——-
Polypeptides
Regulate the immune cell communication
43
NO is both a ——— and ———, their func
Neurotransmitter and local regulator
Func; when the blood oxygen level is low, NO is synthesized from the epithelial cells in the blood vessels———> NO diffuse into surrounding smooth muscle——> vasodilation
In males, production of NO, increase the blood flow in penis, producing an erection
44
3 classes of hormoness
1.polypeptide. example insulin
2. Steroid hormones. Cortisol
3.amines. Epinephrine and tyroxine
45
What are Amine hormones ?
Hormones, synthesized from a single amino acid , either tyrosine or typtophan
46
Are amine hormones water soluble?
All the polypeptide hormones and amine hormones are polar and water soluble except thyroid hormones.
Thyroid hormones- tyroxine T3 is lipid soluble
47
Name the amine hormones example
Tyroxine, epinephrine, triiodothyronine
Serotonin, histamine
48
Name steroid hormone examples
Sex hormones, estrogen, testosterone, progesterone
49
What is the response for epinephrine released from adrenal glands?
Adrenaline——>acts on liver or muscle——> binds to cell surface receptor linked to G protein ———>cAMP——— >activation of protein kinase———>two enzymes
activate ,one breakdown glycogen into glucose , the net result is that the liver releases glucose into the bloodstream, very quickly providing the energy fuel
50
Estrogen receptor is in —————
Tyroxine , vit D, other lipid soluble hormones that are not steroids typically have receptors in the ———
Estrogen-cytoplasmic receptor
Other tyroxine, vit D- nuclear receptor
Receptor-hormone complex interacts with the DNA transcription directly
51
How can a single hormone produce multiple responses?
A single hormone varies response in different target cells with different receptors.
In this way, a single hormone can trigger a range of activities that together bring about a coordinated response to a stimulus
52
Endocrine hormones are from endocrine cells, endocrine cells are grouped in ————
Ductless organs called endocrine glands
Example- testes, ovary, thyroid, parathyroid
53
What endocrine hormone does stomach secrete
Gastrin
54
What are exocrine glands?
Have ducts that carry secreted substances such as sweat and saliva onto the body surface or into the body cavity
55
Pancreas has both endocrine and exocrine glands. What are their respective func
Endocrine glands secrete hormones
Exocrine glands secrete bicarbonate and enzyems
56
What are two hormones secreted by pancreas?
Insulin and glucagon
Insulin- lowers blood glucose level Glucagon- raise blood glucose level
57
The food coming out from stomach contains highly acidic pH. Before it enters duodenum,what must is do?
It must neutralize the high pH.
58
Neuroendocrine pathway, the stimulus is received by ——— rather than endocrine glands.
Sensory neurons
Stimulus received by sensory neurons——> release neurohormone into the blood stream——> travel in the circulations to the target cells.
59
What pathway does milking in mammals use?
Neuroendocrine pathway
Sucking in nipples——>stimulate sensory neurons in nipples——> stimulate the neurohormone posterior pituitary (oxytocin) ——> stimulates the contraction of the mammary glands
60
———— feedback restores the homeostasis of a preexisting stage.
Negative feedback
61
Releasing secretin from duodenum is a negative feedback or positive feedback?
It is a negative feedback. Because the low pH stimulate the secretin secretion——> bicarbonate secretion from the pancreas into the duodenum——> high pH in duodenum ——> eliminating the stimulus thereby shutting off the secretin production
62
Milk sucking from mammary glands positive or negative feedback?
It is a positive feedback, the more sucking——>the more oxytocin——>the more mammary glands contraction
Another type of positive feedback—->giving birth
63
Blood glucose levels are maintained by opposing effects of ——- and ———
Insulin and glucagon
64
In vertebrates, the coordination of endocrine signaling relies heavily on——-
Hypothalamus
Hypothalamus receives information throughout the body and
produce signaling appropriate to the environmental conditions
Eg, when the weather change. Sensory nerves send impulses to hypothalamus ——> regulate the reproductive hormones for the breeding season
65
Where is pituitary both anterior and posterior located ?
Pituitary glands- base of hypothalamus
Posterior pituitary- extension of the hypothalamus, hypothalamus axons secrete neurohormones into the posterior pituitary
Anterior pituitary - an endocrine glands that secret hormones in response to the stimulus from the hypothalamus
66
Hormones secreted from the posterior pituitary
Oxytocin- func related to reproduction and controls milk secretion and giving birth . In addition, oxytocin has target in the brain, influence the behaviors of material care, pair bonding and sexual activity
Vasopressin (ADH)- increases water retention ( fluid build up) , involve in osmoregualation
67
What are the hormones secreted by hypothalamus to control anterior pituitary is called and how are they secreted
Releasing or inhibiting hormones
These hormones are secreted near capillaries at the base of the hypothalamus. The capillaries drain into the portal
veins( short veins) into the anterior pituitary. Direct release to the anterior pituitary.
68
Anterior pituitary hormones are also called————
Tropic hormones
FSH,LH ———>gonadotropins bcuz they relay the signals from the AP to the gonads
69
Where is thyroid gland located?
On the ventral surface of the trachea——> two lobed organ
70
The disease associated with the low level of thyroid hormone
Goiter. Iodine deficiency
Thyroid hormones- only iodine containing molecule synthesized in the body .
Some places- low comsumption of iodine to synthesize thyroid hormone
Low thyroid hormone - stimulate brain and hypothalamus and AP to produce TSH but thyroid hormone cannot be synthesized from thyroid gland. AP——> TSH ———>high level thyroid gland enlarged
71
What is the major target of growth hormone and how does it response?
Major target-liver
Growth hm+ liver——> produce insulin like growth factor—- >bloodstream and stimulate bone and cartilage growth.
GH——> metabolic effects of increasing blood glucose as opposed to effects of insulins
72
What happens when there is hyper or hypo secretion of GH in adult and childhood
Hyper GH in childhood——-> gigantism
Hyper GH in adults —-> affect some bone growth and few parts of the facial features , hands and feet——> acromegaly
Hypo GH in childhood ——> drawfsm
Early detectiiion of the dwarfism——> treatment available with HGH ——> by recombinant DNA
73
Hyperthyroidism features and hypothyroidism features
Hypothyroid patients ——> weight gain , lethargy and intolerance
to cold
Hyperthyroidism ——> weight loss, muscle weakness and profuse sweating
74
What are the direct and indirect effects of PTH?
PTH acts on bone, and kidney directly from Ca uptake and intestines indirectly .
PTH—-> b/d the bone matrix ——> take calcium PTH—-> renale tubules ——> direct intake of calcium
PTH——> stimulate the production of Vit D. Vit D precursors are obtained from food or sunlight on skin. Precursors are converted into vit D in the liver <——PTH acts on kidney to complete the conversion
Vit D——> stimulate uptake of Ca from food in the intestine
Negative feedback is used when blood Ca level arises
75
How does calcium level maintain its homeostasis when Ca level rises?
By the action of Calcitonin.
Calcitonin——> lowers the blood calcium level——> by inhibiting the bone breakdown and + stimulate the excretion of Ca from the kidney
In fishes, rodents, and some other animals, calcitonin is required for Ca2+ homeostasis. In humans, however, calci- tonin is apparently needed only during the extensive bone growth of childhood.
76
Two hormones needed for calcium homeostasis
Calcitonin and parathyroid hormone
Calcitonin- decrease
PTH -increase
77
Are adrenal cortex and adrenal medulla both endocrine glands?
No, adrenal cortex——> endocrine cells
Adrenal medulla————> develop from neural tissue
LIKE AP AND PP
78
What are respective effects of epinephrine on the smooth muscle cells, liver cells and intestinal cells
Liver-epinephrine binds to beta receptor——>activate the protein
kinase A——> glycogen to glucose
Smooth Muscle of the blood vessels ——>beta receptor——> inactivate the muscle specific enzymes——> relaxation of the smooth muscle
Smooth muscle in intestine ——> binds to alpha receptor ——> smooth muscle contraction ——> constrict blood flow to intestine
79
Which hormone from the AP secrete adrenal cortex hormones?
ACTH ( adrenocorticotropic hormones)
Hypothalamus ____stimulate AP——-> ACTH hormone secretion in the blood ———>adrenal cortex——> adrenal cortex hormones
80
What are two examples of adrenal cortex hormones
Glucocorticoids and mineralocorticoids also known as corticosteroids
81
What is the func of glucocorticoids ?
Glucocorticoids also known as cortisols, increase from glucose level from the NONCARBOHYDRATE source, such as PROTEINS.
Glucocorticoids also act on skeletal muscle, causing the breakdown
of muscle proteins into amino acids. These are transported to the liver and kid- neys, converted to glucose, and released into the blood. The synthesis of glucose upon the breakdown of muscle proteins provides circulating fuel when the body requires more glucose than the liver can mobilize from its glycogen stores.
82
What are other func of glucocorticoids other than the raising blood glucose level from proteins
Antiinflammatory response but harmful in long term use as it is a steroid
83
What is the func of minerocortocoids
Salt and water retention , homeostasis
84
What are the func of male sex hormones androgens?
Androgens, the main one testosterone ——> male sexual development in embryo——> secondary sexual characteristics
Puberty——> androgen increase——> vocal cord change , muscle increase
Therefore, athletes take androgens as supplements but side effects liver and testes size and sperm count
Sex hormones are mainly released by the gonads, adrenal cortex small quantities
85
What are the func of female sex hormones
Estrogen and estradiol——> female reproductive system and secondary sex characteristics
Progesterone——> maintaining tissue of the uterus and growth and development of an embryo.
Hypothalamus ——> GnRH——> A.p——> gonadotropin, FSH, LH ——> gonads
86
From which organ is melatonin secreted?
Pineal glands, a small mass of tissue near the centre of mammalian brain
87
Melatonin is secreted at ——— and its func
Night
Func; modified amino acid that regulates func of light and the seasons
Melatonin-sleeping pills
Controlled by a group of neurons in the hypothalamus called SCN Suprachiasmatic nucleus
88
Func of prolactin
The hormone prolactin has an especially broad range of activities. Prolactin stimulates mammary gland growth and milk synthesis in mammals, regulates fat metabolism and reproduction in birds, delays metamorphosis in amphibians, and regulates salt and water balance in freshwater fishes. These varied roles indicate that prolactin is an ancient hormone with functions that have diversified during the evolution of vertebrate groups.
89
Func of MSH
Melanocyte stimulating hormone- skin coloration
Many patients with late-stage cancer, AIDS, tuberculosis, and certain aging disorders suffer from a devas- tating wasting condition called cachexia
MSH receptor associated with cachexia
90
7 products of anterior pituitary
FLAT PEG
FSH
LH
ACTH
TSH
PROLACTIN
ENDORPHIN
GH
91
Prolactin is not released in the presence of ——-
Dopamine
92
Growth hormone increases blood glucose level by
Preventing glucose uptake from certain tissues and stimulate the breakdown of fatty acid. This inrcreases the blood glucose level
93
Hormones that have direct effect and tropic effect
Direct- endorphin, prolactin and growth hormone , MSH
Tropic hormones- work by causing the release of another hormone at organ level
94
T3 and T4 what do the numbers indicate
The numbers of iodine atoms attached
95
Thyroid hormone is associated with ———
Metabolic regulation
96
Goiter is present in —— Hyper thyroid or hypothyroid
Both
97
——— is the precursor for steroid hormones
Cholesterol
98
Type 1 and type 2 diabetes differ by ————
Type 1- autoimmune disease destroying beta cells of pancreas
Type2 - insulin effect ko resist lote tr
99
Four hormones that can increase the blood glucose level
Epinephrine Glucocorticoid Glucagon Growth hormone
100
Somatostatin from pancreas ——— insulin and glucagon
Inhibits both insulin and glucagon
101
Cortisol is from adrenal cortex Catecholamines are from adrenal medulla
The effects of peptide hormones are usually shorter lived, because they work through transient second messenger systems. It is quicker to turn them on and off, compared with steroid hormones, but their effects do not last without relatively constant stimulation. The effects of steroid hormones are long lived
