Hormones and Behaviour Flashcards
What is the definition of a Hormone?
Chemical messages released into the bloodstream that affect the function of target cells at a distance from the source.
List the 3 types of Hormone classifications.
Protein hormones, Monoamine Hormones, Steriod Hormones.
Are most vertebrate hormones Protein Hormones?
a) Yes
b) No
a) Yes
What composes of a Protein Hormone?
A Protein Hormone is composed of Multiple Amino Acids
Define a Peptide Hormone:
A Hormone which is composed of a chain less than 50 animo acids.
Where are Protein Hormones stored before they are release into the bloodstream?
In endocrine cells
Endocrine cells are cells within Endocrine glands (part of the endocrine
List two examples of Protein Hormones:
Insulin (A protein hormone which manages blood glucose levels) and Leptin (A protein hormone which regulates the bodys long-term energy balance (hunger)).
Where are Monoamine Hormones derived from?
A singlular amino acid
List three examples of a Monoamine Hormone:
Seretonin, melatonin, dopamine
Normally end in -ine or -in
Can Monoamine Hormones be regarded as a neurotransmitter?
Why/ Why not?
Yes.
They are able to act on target cells when released into the blood (hormone) AND act locally by crossing synaptic clefts (neurotransmitter)
List 3 examples where steriod hormones are mostly produced:
The Gonads, Adrenal Glands, and The Brain
Describe how Steriod Hormones are composed?
Rings
3x 6 Carbon Rings.
1x 5 Carbon Ring.
What is the precurser to all vertebrate Steriod Hormones?
Cholesterol
Are Steriod Hormones released immediately into the bloodstream?
a) Yes
b) No
a) Yes
Why are Steriod Hormones released immediately into the bloodstream?
Because they are slow-acting.
List 2 examples of Steriod Hormones:
Cortisol (a steriod hormone released when stressed), Testosterone (a steriod hormone associated with male characteristics)
List 3 characteristics of Neurons.
a) Neurons travel along nerve tracks
b) Fast onset and offset
c) Subject to voluntary control
List 3 characteristics of Hormones.
a) Travel throughout the body via the circulatory system.
b) Effects of take minutes/ hours to manifest.
c) No voluntary control of the release
Name where hormones are produced.
Glands
Define a Gland.
A group of cells formed by ingrowth of an epithelial surface
Skin surface which has folded in on itself.
Do all glands produce hormones?
No
Do all hormones come from Glands?
Yes
What are the two types of Glands?
Exocrine Glands and Endocrone Glands.
What type of gland does not make a hormone?
Exocrine Glands
What are 2 features of an Exocrine Gland?
1) They release substances through ducts
2) Substances from Exocrine glands are secreted outside of the body.
Do all Endocrine Glands make Hormones?
Yes
Define an Endocrine Gland
A gland which secretes substances directly into the bloodstream.
What are the two type of receptors for Hormones?
Protein Hormone Receptors and Steriod Hormone Receptors.
What are the 3 characteristics of a Protein Hormone Receptor?
1) They are water soluable; not lipid soluable.
2) Binds to receptor on cell surface.
3) There is a secondary reaction inside the cell.
What are 3 characteristics of a Steriod Hormone Receptor?
1) They are lipid soluable, therefore require a carrier protein in the bloodstream.
2) Leaves carrier protein at target cell.
3) Bind to receptors inside the target cell.
What are the 3 effects when a hormone has interacted with the receptors at the target cell?
1) Enzymatic Pathways
2) Gene Expression
3) Protein Synthesis
What are Enzymatic Pathways?
The chemical reactions which occour inside the targetted cell.
What is gene expression?
Activating/ shutting down a gene for a duration of time.
What is Hormone Sphericity at a receptor cite?
Hormones only bind to receptors which are specfic to that hormone.
What is Hormone Affinity?
Where a hormone connects to receptors easily.
Can dopamine bind to a seretonin receptor cite?
No
Hormones only influence cells with receptors specific to them.
List 2 reasons why receptors only bind hormines with affinity and specifity?
1) So hormones are not over-produced.
2) In a low concentration, hormones will still have a strong effect.
What is Up-Regulation?
When a cell increases the number or receptor cites at a cell.
What is Down-Regulation?
When a cell decreases the production of receptor cites at a cell.
What is an example of positive feedback?
Childbirth
What is an example of negative feedback?
Hunger and Eating
What are the two types of feedback loops?
Positive and Negative feedback
What is the role of a Positive Feedback loop?
To maintain/ accelarate the direction of a stimulus.
What is the role of a Negative Feedback Loop?
To increase/ decrease (to change) the direction of a stimlus.
Describe the process of positive feedback in childbirth:
1) Child presses on mothers cervix.
2) Nerve impulses are sent to the brain to release oxytocin.
3) Oxytocin makes the uterus contract
4) Baby pushes on cervix, starting the process again.
5) Positive feedback loop ends when the baby stops pushing on the cervix.
Describe the process of the negative feedback when an individual eats:
1) Eating substance causes a spike in blood glucose levels.
2) Pancreas detects high levels, and releases insulin.
3) Insulin makes liver absorb glucose, to store glycogen.
4) Blood glucose return to a normal state.
List 3 ways hormones are cleared.
1) Broken down by enzymes
2) The liver removes them
3) Bloodstream Disintergration
How are hormones excreted?
Via bile or urine
Describe the relationship between hormones and behaviour.
Bidirectional
Hormones affect behaviour ~ Behaviour affects hormones.
Name and describe the study where hormones affect behaviour.
Rose et al. (1971): A Rheus monkeys’ showed reduced testosterone concentrations when it lost a fight to another rheus monkey.
Do hormones directly change behaviour? Why/ Why not?
No.
Hormones change the possibility of behavioural responses.
What are the 3 systems which hormones can influence to change an individuals behaviour?
1) Sensory systems
2) Central Processing systems
3) Output systems
How would you check is a behaviour is hormone dependant?
By blocking/ removing the hormone from the body, and reinstating it.
