1/28- Endocrine System (Exam 1) Flashcards
What are the endocrine glands?
No duct and release secretions into blood
Secretions are hormones (chemical messengers)
Discrete structures
Whole reason is to secrete these hormones
Pancreas is both endo and exo
What does a chemical messenger do?
Causes the body to react
Directed to a particular target
- target organ
- target tissue
- target cells (TRUE TARGET)
What 2 organs secrete hormones?
Stomach
Heart
What kind of tissue secretes hormones?
Adipose tissue (fat)
Explain the endocrine and neuron system relationship
Work hand in hand to regulate the body
Line b/n 2 is blurry
Some specialized neurons in the hypothalamus release chemical messengers in the blood
What do axon terminal branches release and in what?
Neurotransmitter
Synaptic cleft
What are neurohormones?
Release of neurotransmitters straight into the blood
What is epinephrine?
Released by endocrine glands into the blood with same effect acting as a hormone
Also released from synaptic cleft
Into blood- adrenaline
Synaptic cleft- epi
What are the 3 major groups hormones are divided in?
1) Amino Acid Derivatives or Amines
- come from amino acids
- polar
2) peptide hormones
- string of amino acids
- polar
3) lipid derivatives
- steroids (built from cholesterol and non polar
What are the 2 ways hormones interact with their target?
1) polar
- hydrophilic
- acts like a magnet
- makes hydrogen bonds
2) nonpolar
- hydrophobic
- lipophilic
Which kind of hormone goes through a phospholipid lipid bilayer?
Non polar
Polar gets spit out
How do polar hormones bring their message to the cell?
Hormone attaches to a receptor protein making it a ligand
Then second messenger (chemical inside cell) delivers the message
What are 2 hormones working together to give the same result called?
Synergist
Action is synergetic
What are 2 hormones working opposite of each other have opposite effects called?
Antagonist
Action is antagonistic
What are the 2 types of synergist hormones and explain
1) additive- 2 hormones doing exactly the same thing
Ex: epi and norepi
2) complimentary- hormones contributing to the same process. Need one to do the other
Ex: FSH and testosterone both contribute to making sperm but for different steps
What is a permissive effect?
Hormone A makes the target more sensitive to Hormone B
What is the primate effect or upregulation?
Hormone A makes the target more sensitive for Hormone A
What is downregulation?
Hormone released too much the target becomes desensitized
What is the half life of a hormone?
Amount of time is takes for the concentration to be reduced by half
Most hormones half life are minutes to hours
Thyroid hormones is days
Are hormones endlessly in the blood?
No, liver and target organs pull out concentrations of the hormone
What are the different types of endocrine glands?
1) pituitary glands or hypophysis
2) thyroid gland
What are the 2 types of the pituitary gland or hypophysis?
1) posterior pituitary
2) anterior pituitary
What is the space between the anterior and posterior pituitary gland?
Rathke’s Pouch
How is the posterior pituitary gland and the thalamus connected?
Infundibulum
