Chapter 8 hormones Part 1 Flashcards
What are hormones?
Chemicals moved by one group of cells and carried through the bloodstream to other parts of the body
What do hormones do?
Act on specific target tissues to produce physiological effects
How are hormones produced?
By endocrine glands
What is endocrine communication?
Hormones released into the bloodstream, selectively affecting distant target organs
What are the different types of chemical communication?
Synapse
Endocrine
Pheromone
Allomone
What are pheromone?
Chemicals released by one animal that affects the behavior or physiology of another animal; usually smell or taste
What is an example of Pheromone communication?
A dog urinating on a landmark(ex.tree) to designate their territory
What is synaptic communication?
Communication via synapses in which a chemical signal is released and diffused across the synaptic cleft to cause change in the postsynaptic membrane
What is allomone communication?
Chemicals released outside the body to affect individuals of another species
What is an example of Allomone communication?
Flowers exuding scent(the Allomone) to attract insects and birds in order to distribute pollen
What are peptide Hormones?
Small protein molecules that are made up of short string of amino acids
What are the different peptide hormones?
- Adrenocorticotropic hormone (ACTH)
- Follicle-stimulating hormone (FSH)
- Luteinizing hormone (LH)
- Thyroid-stimulating hormone (TSH) Growth hormone (GH)
- Prolactin
- Insulin
- Glucagon
- Oxytocin
- Vasopressin
- Corticotropin- a releasing hormone (CRH)
11.Gonadotropin- a releasing hormone(GnRH)
What are Amine Hormones? Aka monoamine hormones
They are modified version of a single amino acid; smaller and simpler
What are the different Amine Hormones?
- Epinephrine (adrenaline)
- Norepinephrine (NE)
- Thyroid hormones (e.g., thyroxine)
- Melatonin
What is Steroid Hormones?
Hormones that are derived from cholesterol and shares it’s structure of four rings of carbon atoms
What are the different steroid hormones?
- Estrogens
- Progestins
- Androgens
- Glucocorticoids
- Mineralocorticoids
How come steroid Hormones pass through the membrane easily?
Because they dissolve readily in lipids
How do Peptide and Amine exert their influence on target organs?
They activate a second messenger inside the cell; by binding to specific receptors on the surface of the cell
How does steroid hormones exert influence over target organs?
It crosses the cell membrane to bind to receptors inside the cell’s nucleus. The steroid receptor complex then binds to specific DNA regions to control the expressions of that specific gene
Steroid hormones are typically more slow acting than peptide and amine hormones
Examples of steroids having their own specific receptors
Estrogens selectively interact with estrogen; androgens(testosterone) bonds to androgen receptor
What is the pituitary gland?
A type of endocrine gland that releases important hormones and regulate other endocrine glands
What is the pituitary stalk?
It’s a thin piece of tissue that connect the pituitary gland to the hypothalamus
What are Neuroendocrine cells?
Neurons that release hormones into the bloodstream (not the synapse)
How does the neuroendocrine release hormones into the bloodstream?
They receive a synaptic input from other neurons and produce action potential(only if excited past threshold)
What does the posterior pituitary do?
Release hormones
What two hormones do neuroendocrine release from the posterior pituitary?
Oxytocin and Vasopressin
What is oxytocin?
It is a hormone responsible for reproductive and parental behavior, stimulating contractions, triggers milk letdown reflexes, also released in orgasm in men and women
What is Vasopressin?
A hormone that activates nerve cells regulated to thirst and water regulation, increase blood pressure, and form pair bonds
What are pair bonds?
A durable and exclusive relationship between two individuals
How are hormones released from the neuroendocrine cells regulated?
By negative feedback
What is negative feedback?
When the output of a system feeds back to recur the effects of input signals
What is an example of negative feed back?
The thermostat being set to a different temperature at a different time
Hormones released from neurodocrine cells have what type of feedback?
Negative feedback
