module 5 - 14.1 hormonal communication Flashcards
What is the endocrine system?
Works alongside the neuronal system to react to charges in the body/environment and bring about the most appropriate response
What are endocrine cards?
- Make up endocrine system
- group of specialised subs that secrete hormones
- secrete directly into the blood and have no ducts
What are hormones?
- ‘Chemical messengers’
- any member of a signalling molecule produced by glands in multicellular organisms transported by me circulatory system to target organs to regulate behaviour and physiology
- released directly into blood plasma (under nervous or hormonal control)
- diffuse out blood plasma & stimulate trajet aus to produce correct response
What are me 2 types of hormones?
- Amino acid based hormones
- steroid based hormones
What are amino acid based hormones?
- Proteins e.g. Insulin
- Glycoproteins e.g. FSH
- polypeptides e.g. ADH
- amines
- tyrosine derivatives
What are amones?
- Breakdown of amino acids releases amines
-many neurotransmitters are also amines (e.g. Adrenaline and noradrenaline)
What are steroid based hormones?
- Based on cholesterol
- example are the sex hormones oestrogen & testosterone
What are the mechanisms for the action of steroid based hormones?
- lipid soluble so con dissolve through cell membrane:
1. Entering a cell
2. Binding to a receptor protein in the nucleus
3. mRNA synthesis (first step of protein synthesis. - long acting
What are the mechanisms for the action of non-steroid based hormones?
- Water soluble so can’t dissolve through au membrane:
1. Binding with receptors
2. Cell signalling pathway using second messengers
3. Transcription factors being activated in the nucleus, and protein synthesis beginning - cascade within a cell → rapid response
compare hormonal and neuronal communication
HORMONAL COMMUNICATION
- communication is slow
- communication is by chemicals (hormones)
- travel to all parts of the body but only target organs respond
- widespread
- response is slow and long lasting
- effects may be permanent
NEURONAL COMMUNICATION
- communication is fast
- communication is by nerve imprises
- neurones travel to specific parts of the body
- localised
- rapid response but short-lived
- effects may be temporary
What are adrenal glands?
- example of an endocrine gland
- adrenal cortex (outer layer), adrenal medulla (inside cortex)
What is the adrenal cortex?
- Produces hormones vital to life
- produces steroid based hormones
- under control of hormones produced by pituitary gland
- releases 3 groups of hormones
Which 3 groups of long-term hormones does the adrenal gland release?
- Glucocorticoids
- mineralocorticoids
- androgens
What is the adrenal medulla?
- Produces non-essential hormones
- produces amine based hormones
- hormones released when body is under stress
- under control of sympathetic nervous system
- Releases 2 hormones
Which 2 hormones does me adrenal medulla release?
- Adrenaline
- noradrenaline
What hormones does the pituitary gland produce?
- growth hormone
- anti-diuretic hormone
Gonadotrophins
What is the function of the hormones produced by the pituitary gland?
- Controls bone and muscle growth
- increases reabsorption of water in kidneys
- controls development of ovaries/testes
Which hormone does the thyroid gland produce?
Thyroxine
What is the function of the thyroxine?
- controls rate of metabolism
- controls rate of glucose used in respiration
- promotes growth
What hormone does the adrenal gland produce?
Adrenaline
What is the function of the adrenaline?
- increases heart/breathing rate
-raises blood sugar level
What hormone do the testes produce?
Testosterone
What is the function of testosterone?
Controls sperm production and secondary sexual characteristics
Which hormone does the pineal gland produce?
Melatonin
What is the function of melatonin?
- Affects reproductive development
- controls daily cycle
Which hormones do the pancreas produce?
- Insulin
- glucagon
