RVT- Endocrine Flashcards
1
Q
How does the nervous system convey its information?
A
High speed electrical signals along specialized cells called neurons. These signals regulate other cells
2
Q
How does the endocrine system convey its messages?
A
Secrete hormones that coordinate slower but longer lasting responses
3
Q
What is the primary function of the endocrine system?
A
Produce hormones
4
Q
How do hormones travel through the body?
A
Through the blood stream but only affecting tissues that have specific target receptors
5
Q
What is the difference between primary and secondary endocrine glands?
A
Primary only produce hormones
Secondary produce hormones and other products
6
Q
What are examples of primary endocrine glands?
A
Pituitary
Thyroid
Pineal
Parathyroid
7
Q
What are examples of secondary endocrine glands?
A
Pancreas Hypothalamus Thymus Liver Kidneys Stomach Duodenum
8
Q
What are the 5 methods of intercellular communication by secreted hormones?
A
Endocrine signalling Paracrine signalling Autocrine signalling Synaptic signalling Neuroendocrine signalling
9
Q
What is endocrine signalling?
A
Cell to cell
Blood vessels are involved
10
Q
What is paracrine signalling?
A
Cell/organ releases hormones into interstitial tissues
No blood vessels involved
Short distances
11
Q
What is autocrine signalling?
A
The cell produces hormones and uses it within itself
No blood vessels involved
Short distances
12
Q
What is synaptic signalling?
A
Not using hormones
Synaptic signals within neurotransmitters using chemicals
13
Q
What is neuro-endocrine signalling?
A
Uses neurotransmitters as well as hormones. Involves the use of blood vessels. Starts with nervous system and ends in non-nervous.
14
Q
What is the most common method of intercellular communication by secreted hormones?
A
Endocrine
15
Q
What are the 3 chemical classes of hormones?
A
Polypeptides ( hydrophilic)
Steroids (hydrophobic)
Amines
16
Q
What is an example of a polypeptide?
A
Insulin
Glucagon
Growth hormone
Prolactin
17
Q
What is an example of a steroid hormone?
A
Cortisol
Testosterone
Estrogen
18
Q
What is an example of an amine hormone?
A
Epinephrine
Norenephrine
Thyroxine
Dopamine
19
Q
What is the significance of the steroid class of hormone in relation to their structure?
A
The steroidal hormones are hydrophobic and can easily pass into the nucleus of the cell affecting the RNA
They can change cell function.
20
Q
How do hydrophilic hormones affect cells?
A
They attach to the cell membrane but require a receptor to bring them into the cell.
Not dangerous to the cell.
21
Q
Where are amine hormones produced?
A
The medulla of the adrenal glands
22
Q
What long term processes are the endocrine system responsible for?
A
Development of the animals growth and reproduction.
23
Q
Most hormones circulate freely and do not last long. How do they get broken down and eliminated in the body?
A
Liver and kidneys as well as enzymes in the plasma or interstitial fluid
24
Q
How can a hormone be maintained in the body longer?
A
Some hormones are bound to a carrier molecule that increases their duration in the body. Once released from the carrier, they get broken down.
25
What are the 2 hormones that the hypothalamus produces?
Oxytocin
| Anti-diuretic hormone
26
Where are these hormones stored?
The posterior pituitary gland
27
What is the negative feedback loop?
It is a reaction that causes a decrease in function. Occurs in response to a hormonal stimulus
28
The pituitary is an example of a primary or secondary gland?
Primary
29
What gland is considered the master gland?
Pituitary
30
What are parathyroid glands?
Very tiny glands embedded within the thyroid gland
31
What is the hormone that is produced by the medulla of the adrenal gland?
Epinephrine
| Norenephrine
32
What gland is the only one to have a direct link to the brain?
Pituitary gland
33
What is the natural cascade for hormone production?
The hypothalamus sends a message to the pituitary gland. Pituitary then communicates with the appropriate gland to address the problem
34
Which body system detects low metabolism?
The brain
35
How does the hypothalamus communicate to the pituitary gland to encourage thyroid hormone production?
The hypothalamus sends out thyroid releasing factor to the pituitary gland. The P gland produces thyroid stimulating hormone which goes to the thyroid which stimulates it to produce the hormone.
36
What 2 hormones are stored in the posterior pituitary gland and what are they known as?
Oxytocin
ADH
Known as neurohormones
37
What does oxytocin do and what regulates it?
It stimulates contraction of uterus as well as stimulation of mammary glands to 'let down' milk
Regulated by nervous system
38
What does anti-diuretic hormone do?
| What regulates it?
Promotes retention of water by the kidneys
| Regulated by water/salt balance
39
What hormones are found in the anterior pituitary gland?
```
Follicular stimulating hormone
Leutinizing hormone
Adrenocorticotropic hormone
Thyroid stimulating hormone
Growth hormone
Prolactin
```
40
What does growth hormone do and what regulates it?
```
Stimulates growth (esp bones) and metabolic function.
Regulated by hypothalamic
```
41
What does prolactin do?
| Regulated by?
Stimulates milk production and excretion.
| Regulated by hypothalamic hormones
42
What does follicle stimulating hormone do?
| Regulated by?
Stimulates production of ova and sperm.
| Regulated by hypothalamic hormones
43
What does the thyroid stimulating hormone do?
| Regulated by?
Stimulates the thyroid gland.
| Regulated by hypothalamic hormones
44
What does the adrenocorticotropic hormone do?
| Regulated by?
Stimulates the adrenal cortex to secrete glucocorticoids.
| Regulated by the hypothalamic hormones.
45
What does the thyroid gland produce?
T3 and T4
| Calcitonin
46
What do T3 and T4 do?
| What regulates them?
Stimulate and maintain metabolic processes.
| Regulated by thyroid stimulating hormone
47
What does calcitonin do?
| Regulated by?
Lowers blood calcium level
| Regulated by calcium in the blood
48
What hormone is produced by the parathyroid gland?
Parathyroid hormone
49
What does parathyroid hormone do?
| Regulated by?
Raises the blood calcium level
| Regulated by calcium in the blood
50
What two hormones regulate blood calcium levels?
Parathyroid hormone
| Calcitonin
51
What hormones are produced in the pancreas?
Insulin
| Glucagon
52
What does insulin do?
| Regulated by?
Lowers blood glucose level
| Regulated by glucose in the blood
53
What does glucagon do?
| Regulated by?
Raises blood glucose level.
| Regulated by glucose in the blood
54
What hormones are produced by the adrenal glands?
Medulla - epinephrine and Norenephrine
| Cortex- Glucocorticoids and mineralocorticoids
55
What does epinephrine and Norenephrine do?
| Regulated by?
Raise blood glucose levels
Increase metabolic activities
Constrict certain blood vessels
*regulated by nervous system
56
What 4 hormones are involved in raising blood glucose levels?
Epinephrine
Norenephrine
Glucagon
Glucocorticoids
57
What do glucocorticoids do?
| Regulated by?
Raise blood glucose levels
| Regulated by ACTH
58
What do mineralocorticoids do?
| Regulated by?
Promote sodium reabsorption
Promote potassium secretion
*Raise sodium levels, Lower potassium levels
Regulated by potassium in the blood and angiotensin II
59
What hormone is regulated by angiotensin II?
Mineralocorticoids
60
What hormones are produced in the gonads?
Testes- Androgen
Ovaries- Estrogen
Progestin
61
What do androgens do? What is the primary androgen?
| Regulated by?
Support sperm formation
| Promote development and maintenance of male secondary sex characteristics
62
What do estrogens do?
| Regulated by?
Stimulate uterine lining growth
Promote development and maintenance of secondary sex characteristics
Regulated by FSH and LH
63
What do progestins do?
| Regulated by?
Promote uterine lining growth
| Regulated by FSH and LH
64
What two systems maintain homeostasis in the body?
Nervous system and the endocrine system
65
What hormone does the pineal gland produce?
| What regulates it?
Melatonin
| Dark and light cycles
66
What does melatonin do?
Involved in biological rhythms
67
What are the 6 differences between the posterior and anterior pituitary glands?
Size (Anterior is larger)
Color (Anterior is reddish/Posterior is white)
Type of connection
Hormones production ( one produces/one does not)
Posterior has faster reaction time due to nerves
Names - Hypothesis/hypophesis
68
What is the other name for the anterior pituitary gland?
Hypothesis and Adenohypophysis
69
What is the other name for the posterior pituitary gland?
Hypophysis and neurohypophysis
70
Which part of the pituitary gland receives messages quicker?
Hypophysis/neurohypophysis/posterior pituitary gland
| It is directly connected to the hypothalamus
71
What does the hypothalamus release to the hypothesis?
Inhibitory or releasing hormones through the portal blood veins
72
How are ADH and oxytocin released into the bloodstream?
By Nerve impulses from the hypothalamus
73
Which part of the pituitary gland is most rostral?
Anterior/hypothesis/adrenohypophysis
74
How does the anterior pituitary gland receive messages?
| How does the posterior pituitary gland receive messages?
Anterior- receives messages through hypothelial portal vessels.
Posterior- receives messages though nerve tracts
75
What is the area separating the hypothalamus and pituitary gland called?
Hypothysial stock
76
A very active thyroid gland will result in......
| A under active thyroid gland will result in....
High body temp
Thin body
Low thyroid levels=obesity
77
What is heat seeking syndrome?
Body temp is low due to low thyroid hormone
78
Which hormone kicks in when an animal is stressed?
ACTH
79
What is the 'feel-good' hormone?
Oxytocin
80
Where do we see melanocytes?
Brightly pigmented animals like birds and fish
81
In diabetes insipidus we would see a lack of what hormone?
Anti-diuretic hormone
82
What are the other 2 names for growth hormone?
Somatotropin
| Somatotropic
83
What does growth hormone do?
Helps regulate the metabolism of proteins, carbohydrates and lipids in all the body's cells
Promotes growth in young animals
84
Which hormone triggers and maintains lactation?
Prolactin- It's production and release continues as long as the teat continues to be stimulated by nursing
85
Which hormone stimulates the growth and development of the thyroid gland?
Thyroid stimulating hormone. Aka- thyrotropic hormone
86
Which hormone stimulates growth and development of the adrenal cortex?
ACTH
87
How can ACTH be released quickly?
Hypothalamus receives stimulation from the brain...it then sends a burst of ACTH releasing factor to the anterior pituitary through the portal system causing ACTH release
88
Which hormone stimulates cells that line the follicles to produce and secrete estrogens?
Follicular stimulating hormone
89
What causes anti diuretic hormone release?
Receptors in the hypo detect changes in osmotic pressure of blood that result from dehydration/hemoconcentration. This generates nerve impulses that cause release of ADH...ADH goes to kidneys and tells them to reabsorb more water and put in bloodstream.
90
If there is a lack of anti diuretic hormone in the body, what will be the result?
Excessive urine
91
If there is an excess of anti diuretic hormone in the body, what will happen?
Not enough urine produced
92
Which hormones induces uterine contractions that aid transport of spermatozoa to the oviducts?
Oxytocin.....also stimulates uterine contracting that aid in the delivery of the fetus and the placenta
93
Where do you find the thyroid gland?
Two lobes on either side of the trachea
94
What connects the two lobes of the thyroid gland?
Isthmus (stringy part)
95
When is T3 and T4 produced?
When thyroid stimulating hormone from the anterior pituitary reaches the thyroid gland
96
What does T4 do?
Controls the rate at which glucose is burned in the body
97
Which hormone influences the development and maturation of the CNS and growth and development of muscles and bones?
Thyroid hormones
98
What hormone allows an animal to generate heat and maintain a constant internal body temperature?
Thyroid hormones
99
Which hormone has a calorigenic affect?
Thyroid hormones
100
Much like growth hormone...what hormone affects metabolism of proteins, carbs and lipids?
Thyroid hormones
101
What is produced by C cells, located between the thyroid follicles?
Calcitonin
102
How does calcitonin work?
Lowers blood calcium. Prevents hypercalcemia by encouraging excess calcium to be deposited in the bones.
103
What is parathormone and where is it produced?
Parathyroid hormone produced in the parathyroid gland which are small pale nodules in, on or near the thyroid glands.
Increase calcium levels in the blood
104
What hormone prevents hypocalcemia?
Parathyroid hormone/parathormone
105
How does parathyroid work to increase blood calcium levels?
Causes kidneys to retain calcium and intestine to absorb calcium from food, as well as withdrawing calcium from the bones
106
Parafollicular cells are also known as...
C cells
107
Which hormone in the body encourages osteoclasts?
Parathyroid hormone
108
What is an antagonist to estrogen?
Estrogen and Parathyroid are antagonists...when female animals stop producing estrogen, the parathyroid hormone goes unregulated and takes calcium from the bones= osteoporosis
109
What hormones are affected when under stress?
Adrenal medulla-secretes epinephrine and Norenephrine
Adrenal cortex - secretes glucocorticoids and mineralocorticoids (from ACTH)
-immune system suppression
-increased blood glucose
-increased blood pressure
110
What hormone secreting organ is near the duodenum and has both endocrine and exocrine function?
Pancreas
111
What are the three hormone producing cells in the pancreas and what do they produce?
Alpha cells- produce glucagon
Beta cells- produce insulin
Delta cells- produce somatostatin
112
What are these pancreatic hormone producing groups of cells called?
Pancreatic islets (Islets of Langerhans)
113
How is homeostasis achieved after blood glucose levels rise after a carb rich meal?
Beta cells of pancreas release insulin into the blood
Cells and liver take up glucose
Blood glucose than declines
114
How is homeostasis achieved when the blood sugar levels drop after skipping a meal?
Alpha cells of the pancreas release glucagon into the blood
| The liver breaks down glycogen and releases glucose into the blood causing the blood glucose levels to rise
115
What is diabetes mellitus?
Caused by a deficiency of insulin or a decreased response to insulin in target tissues
116
What is the difference between Type 1 and Type 2 diabetes mellitus?
Type 1- autoimmune disorder in which immune system destroys pancreatic beta cells
Type 2- Involves insulin deficiency or reduced response of target cells due to change in insulin receptors
117
Where does spermatozoa maturation occur?
Sartorial cells
118
Where is androgen produces in the teste?
Interstitial cells: clumps of endocrine cells = leydig cells
119
Ovaries are affected by what hormones?
Follicle stimulating hormone
| Leutinizing hormone
120
As the follicle grows how is estrogen affected?
Estrogen increases acceleration of physical and behavioural changes
121
Follicular stimulating hormone stimulates ovarian follicles to develop.....where is estrogen produced?
Cells of the follicles produce and release estrogens
122
Where is progesterone produced and what does it do?
Produced in corpus luteum
*principle progestin
Helps prepare uterus to receive the fertilized ovum also needed to maintain pregnancy
123
What hormone does the kidney produce?
Erythropoietin- stimulates red bone marrow to increase production of rbc's
Renin-an enzyme that plays an important role in the renin-angiotensin-aldosterone hormonal system
124
What hormone does the stomach produce and where is it produced?
Gastric- produced by the cells in the wall of the stomach
| Secretion is stimulated by the presence of food in the stomach
125
What does gastrin stimulate the gastric glands to secrete?
Hydochloric acid and digestive enzymes
126
What is the correlation between cortisol and gastrin?
Cortisol is released during stress....which causes an increase in gastrin....acid in stomach with no food = ulcer
127
What 2 hormones are released in the small intestines?
Secretin and Cholecystokinen
| *produced by cells in the lining of the small intestine
128
Why does the small intestine produce secretin and Cholecystokinen ?
Secretion occurs in response of chyme in the duodenum. Secretion stimulates pancreas to secrete fluid to neutralize acidic chyme
Cholecystokinen stimulates pancreas to release digestive enzymes into the duodenum
129
What hormones does the placenta produce and when?
Estrogen and progesterone to support and maintain pregnancy...only produced during the 3rd trimester
130
What hormones does the thymus produce?
Thymosin and thymopoietin - chemical substances
| Seems to cause certain cells to be transformed into T-Lymphocytes
131
What hormone may play a role in the timing of seasonal estrous cycles in some species?
Melatonin from the pineal gland
132
What substance is used to block receptors of certain tissues and is produced in a variety of body tissues? Nine main groups A-I?
Prostaglandin
133
Where do all glands originate from?
All glands originate from epithelial tissue
Exocrine glands still connected to the surface
Endocrine where invaginate do into tissue
134
What is endocrinology?
Science that deals with a group of ductless glands and the action of their secretions which are transported via the blood stream
135
What organ releases the hormones Leptin and Resisten?
Adipose tissue
| Leptin increases appetite
136
What are steroids derived from?
Lipid like compounds derived from cholesterol
137
What are the 3 ways that hormones can be produced?
Humoral- substances other than hormones control the secretion of endocrine glands ie nutrient/ion level
Neural- nervous system senses something wrong and stimulates
Hormonal-hormones from one gland stimulate the release of hormone from another gland.
138
How many zones does the cortex of the adrenal gland have?
3 zones
139
To increase blood calcium levels, (hypocalcemia)what 3 body parts does parathyroid hormone affect?
Bone- stimulates osteoclasts to break down bone matrix to release calcium into the blood
Intestines- Increases calcium absorption from food
Kidney- Promotes activation of Vitamin D and increased calcium reabsorption
140
How do prostaglandins travel to their target tissues/organs?
They do not travel in the bloodstream. They are local or tissue hormones that act locally or within the tissue they originate from
141
What hormones use a second messenger molecule to promote a response of the target cell?
Amino acid or peptide hormones
| Not steroid or prostaglandin
142
What are the 3 mechanisms of hormone release?
Humoral- substances other than hormones control their secretion of endocrine glands
Neural-Nervous system stimulates the endocrine gland to release hormones
Hormonal- hormones from one gland stimulate the hormones of another gland
143
What are examples of humoral hormones?
```
Calcitonin
Glucagon
Insulin
Parathyroid
Mineralocorticoids
Melatonin
```
144
What are examples of neural hormone mechanism?
Oxytocin
Norenephrine
Epinephrine
145
What is vasopressin also known as?
Anti-diuretic hormone
146
What is the other name for luteinizing hormone?
In males- Interstitial cell stimulating hormone IcSH
147
What is another name for C cells?
Parafollicular cells ( where calcitonin is produced)
148
What hormones are amino acid derivatives?
Epinephrine
Norenephrine
Thyroxine
Melatonin
149
Thyroxine is a thyroid hormone called T3. True or false?
False - Thyroxine is T4
150
```
Which of the following does not chemically belong with the other hormones?
ADH
PTH
GH
PRL
```
ADH
151
What is goiter?
An enlarged thyroid gland
152
What is a long term stress response hormone?
Glucocorticoids
| Mineralocorticoids
153
What are short term stress response hormones?
Epinephrine
| Norenephrine
154
Fluid balance regulation is controlled by what hormones?
Anti-diuretic hormone
| Aldosterone
