Endocrine L1: Introduction of Endocrine System Flashcards
What are the 2 control systems that are needed to maintain homeostasis?
- milliseconds – minutes = nervous system
- minutes – hours – days – years – entire lifetime = endocrine system
How does the nervous system connect to the rest of the system?
Fast response: milliseconds – minutes
Use nerves to connect to all the systems (need to be specific)
How does the endocrine system connect to the rest of the system?
minutes – hours – days – years – entire lifetime
Uses blood to connect all the systems
What is the neuroendocrine system?
Endocrine and nervous system work together
What are 6 functions of the endocrine system?
- regulate metabolism, water and electrolyte balance
- allow body to cope with stress
- regulate growth
- control reproduction
- regulate circulation and red blood cell production
- control digestion & absorption of food
What are the 2 blood-borne chemical messengers?
- Hormones
- Neurohormones
Hormones and neurohormones are _______ chemical messengers.
blood-borne
What does blood-borne mean?
Spread around through blood
What is the difference between the hormones and the neurohormones?
- Hormone- produced by a endocrine cell
- Neurohormone- produced by a nerve cells
What is a hormone produced by?
produced by a endocrine cell
What is a neurohormone produced by?
Produced by a nerve cell
What makes hormones work?
Target cells which have receptors respond to the hormones
What are 3 examples of hormones?
- Estrogen- for males and female
- Helps with bone mineral density
- Adrenaline
- Neurohormone and a neurotransmitter
- Important for controlling stress and CV
- Testosterone
- Steroid hormone (usually all reproduction hormones)
- Made from cholesterol (fat)
- Produced in the testes
- Target organ - testes
- Main role- sperm production
- How is it regulated? (which organ)- brain (centrally)
What type of hormone is testosterone?
Steroid hormone
What is testosterone made of?
Cholesterol (fat)
Where is testosterone produce by?
Testes
What is the target organ of testosterone?
Testes
What is the main role of testosterone?
Sperm production
How is testosterone regulated?
Brain (centrally)
What is the endocrine system?
all hormone-secreting tissues; including, in the brain, the hypothalamus, pituitary & pineal gland, and in the periphery the thyroid, parathyroid & adrenal glands, gonads, pancreas, kidneys, liver, thymus, and also parts of the intestines, the heart and skin.
What is the function of pituitary gland?
3rd eye
- Produce melatonin
What are the 3 classes of hormones (have different characteristics = different function)?
- Peptides
- Amines
- Steroids
What are the chemical classification of hormones?
What are peptides hormones?
- chains of amino acids,
- Hydrophilic (ie water soluble).
- Stored prior to release.
eg ADH, growth hormone.
What does hydrophilic mean?
Likes water = able to be dissolved
Not like fat = can’t dissolve
What are amines hormones?
- derived from the amino acid ‘tyrosine’.
- All are stored.
- Hydrophilic - catecholamines (adrenaline, noradrenaline & dopamine);
- Lipophilic (ie fat soluble): thyroid hormones.
What are the 2 types of amines hormones?
- Hydrophilic
- Lipohilic
How does tyrosine get into the body?
derived from the amino acid ‘tyrosine’. All are stored. Hydrophilic - catecholamines (adrenaline, noradrenaline & dopamine); or Lipophilic (ie fat soluble): thyroid hormones.
What are steroid hormones?
- derived from cholesterol where appropriate enzymes for conversion are present
- Lipophilic.
- Not stored
- released by diffusion.
eg cortisol, testosterone, oestrogens.
What are 4 characteristics of hydrophilic hormones?
- Most transported in blood dissolved in plasma (some also carried on binding proteins).
- Can’t pass through cell membrane, therefore binds to specific receptors on surface of target cell.
- Must work on the outside of the cell
- Elicit response either by changing cell permeability (few) or by activating ‘second-messenger’ system to alter activity of intracellular proteins (most).
- Vulnerable to metabolic inactivation so short-term effects
What are 2 types of hydrophilic hormones?
- peptides
- catecholamines
Hydrophilic hormones are mostly transported in _____ dissolved in plasma (some also carried on binding proteins).
blood
Can hydrophilic hormones pass through cell membrane? How do they work?
No
Can’t pass through cell membrane, therefore binds to specific receptors on surface of target cell.
Must work on the outside of the cell
What are 2 ways the hydrophilic hormones elicit a response?
- changing cell permeability (few)
- by activating ‘second-messenger’ system to alter activity of intracellular proteins (most).
Hydrophilic hormones ____ are/aren’t vulnerable to metabolic inactivation so there are ____ (long/short) term effects.
are; short