UW BIOLOGY 100 UNIT 1 FINAL REVIEW
can you quiz/help me study for my quiz? heres my study guide filled out: “What is a drug?”; Substances that are drugs or not
A drug is a substance that is not nutritional and alters your body function.
-Drugs: coffee, marijuana, heroin
-Non-drugs: water, sugar
What is a psychoactive drug?
A substance that affects the CNS and perception
What is a licit drug?
Legal drugs (coffee, alcohol, etc.)
What is an illicit drug?
Illegal drugs (mushrooms, cocaine, etc.)
What is an over-the-counter drug?
Drugs easily available without a prescription
Psychosocial model of addiction vs disease model of addiction
Psychosocial – choosing to use drugs
Disease – legit disease
Medical/legal definition of addiction.
Individuals developing overwhelming compulsions for drugs or other activities.
What is tolerance?
Needing an increased dosage/amount to get the same feeling again
What is withdrawal?
The negative symptoms users face after abruptly stopping the usage of the drug.
How do withdrawal symptoms relate to the normal effects of a drug?
Withdrawl symptoms are the opposite of the normal effects of the drug.
What is dependence to a drug?
Needing the drug to feel normal and live normally.
Explain receptor site theory explains why drugs have an effect on our brain:
The ligand (normal) can produce the effect, but also can the agonist (drug) or opposite antagonists (drugs).
What is a receptor?
A protein that when a molecule binds to it, produces an certain effect.
What is a ligand?
A naturally occurring substance that binds to a receptor to produce an effect.
What is an agonist?
A drug that binds to the receptor, imitating the effect of the ligand.
What is an antagonist?
A drug that binds to the receptor, to produce the opposite effect of the ligand.
What effect do agonists and antagonists have on receptors/cells?
They imitate or produce opposite effects.
Lesson 2:
Central Nervous System (CNS) - What body parts are included in the CNS?
Brain and spinal cord.
Peripheral Nervous System (PNS) - What body parts are included in the PNS?
Everything else in the NS (the nerves)
Somatic Nervous System function:
Sensory and motor
Autonomic Nervous System function:
Automatic functions, nerve cells, ganglia
Sympathetic Nervous System function:
Fight or flight – blood to muscles, lungs, brain
Parasympathetic Nervous System function:
Rest and digest – blood to skin and digestive track
Be able to explain what might happen to someone’s body if they took a drug that activated their sympathetic or parasympathetic nervous system:
Sympathetic – they feel more active; HR goes up, anxiety goes up, breathing goes up
Parasympathetic – they feel calm; HR goes down, anxiety goes down, breathing goes down
Lesson 3:
What did we learn from Phineas Gage?
Railroad worker who blew the top of his head off with dynamite, discovered the frontal lobe controls your personality.
What did we learn from Von Economo?
A neuroscientist researching sleeping disease discovered that the brain stem helps communicate.
What did we learn from Patient HM?
A patient who cut his hippocampus out to help with his seizures, but couldn’t remember anything, discovered the hippocampus is tied to (short term) memory.
Function and location:[H01]
Meninges
A layer of tissues around the brain that help protect the brain
Cortex/Cerebrum:
The main section of the brain (5 lobes) that dopamine gets sent to.
Frontal Lobe
In the front section of the brain, problem solving/deep thinking and emotions
Temporal Lobe
On the sides of your brain, hearing
Parietal Lobe
On the top back of the brain, movements and touch
Occipital Lobe
In the back of your brain, vision
Insular Lobe (AKA Insula)
Folded inside your cerebrum that is thought to be associate with cravings
Corpus Callosum
In the middle, the connector between the 2 halves of the brain
Thalamus
In the center of the brain (under the corpus collosum), the secretary of the brain
Hypothalamus
In the center of the brain (under the thalamus), regulates autonomic NS
Cerebellum
In the back of the brain, under the cerebrum, small movements
Brain Stem
In the bottom center of the brain, regulates autonomic N
Hippocampus
In the center of the brain, responsible for memory
Amygdala
In the center of the brain (above hippocampus), responsible for fear and emotional memories
VTA
In the reward pathway (center of brain), makes dopamine
Nucleus Accumbens
In the reward pathway (center of brain), stores dopamine
Structures in pathway, order
Learning Pathway
Sensory organ --> thalamus --> frontal cortex or hippocampus
Sensing Pathway
Sensory organ --> thalamus --> frontal cortex (differs)
Which of the 5 senses does NOT follow the trend for sensing pathways?
Smell
Limbic Pathway
Hippocampus --> amygdala --> frontal lobe
Reticular Pathway
Thalamus --> hypothalamus --> brain stem
Reward Pathway
VTA --> NA --> cerebrum
Lesson 4
Neurons
Know the 4 parts of a neuron (both name, and be able to identify them on a neuron drawing)
Dendrites (A), axon (C), soma (B), axon terminal (F)
What is “resting potential?”
When the neuron is negative on the inside because proteins push out 3 Na+ out and 2 K+ goes in.
What is “action potential?”
The moment between when Na+ moves in to make the cell more positive (depolarization) and K+ moves out to make the cell less positive (repolarization) to fire a message quickly.
Membrane Proteins
What is a receptor?
A protein that molecules bind to, producing an effect.
What is a channel?
A protein that does not control direction allows normal diffusion.
What is a pump?
A protein that does control direction, uses energy to move against the concentration gradient.
How is a channel different from a pump?
Channels move with the natural direction, pumps move against it. Pumps use energy, channels do not.
What is a “concentration gradient” and how does it control movement of molecules?
The amount of molecules in two different areas.
Resting Potential
What direction does an action potential travel on a neuron?
Towards the axon terminal by moving down from each area that are depolarizing
Know what happens with a membrane pump, sodium ions, and potassium ions to get the cell ready for resting potential
Resting potential uses a Na/K pump that brings 2 Na+ ions out of the cell and brings in 3 K+ ions into the cell.
How many sodium and potassium ions are moved by the pump? In what direction?
2 Na+ out, 3 K+ in.
What is the electricity inside the cell compared to outside the cell during resting potential?
The cell is more negative inside the cell compared to outside during resting potential.
Action Potential
How do sodium and potassium ions, channels, and pumps work together to move an action potential down the cell?
Potassium ions want to go outside, sodium ions want to go inside, so the Na/K pump is bringing the ions in and out and the action potential moves down to the next pump.
Which direction are sodium and potassium ions moving to create action potential?
Na+ is going in and K+ is going out.
How does the electricity inside the cell compare to outside the cell during action potential?
The inside of the cell becomes more positive than the outside.
What are “depolarization” and “repolarization” in terms of action potentials?
Depolarization – Na+ moves in, cell becomes more positive
Repolarization – K+ moves out, cell loses positives
Lesson 5: Neurotransmitters and Synapses
Synapse
What is the “presynaptic neuron?”
The neuron that sends the signal to another neuron.
What is the “postsynaptic neuron?”
The neuron that receives the message from the presynaptic neuron.
Where are synapses found (ie at the meeting point of what two types of cells?)?]
The entire section of the neurons that is talking to each other. (presynaptic neuron, postsynaptic neuron, synpatic cleft)
What is a vesicle?
A membrane that holds neurotransmitters to be released.
What happens to neurotransmitters AFTER they bind to receptors (two different things)?
-Enzyme break the neurotransmitters down
-The presynaptic neuron takes it up using the vesicles (new action potential)
Neurotransmitters
What is a neurotransmitter?
A chemical signal that helps cells communicate.
What job do neurotransmitters do?
Passes chemical messages from one neuron to the next.
What is the difference between an excitatory and an inhibitory neurotransmitter?
Excitatory – The sudden increase of positive Na+ ions in the postsynaptic neuron causes an AP to fire
Inhibitory – The sudden increase of negative CI- ions in the postsynaptic neuron makes the neuron remain at rest.
Synaptic Transmission
Be able to explain, step by step, how a message is passed from one neuron to another.
Your explanations should be able to show how this is different if inhibitory NTs are used for the message vs. excitatory NTs are used for the message
1. An action potential reaches the axon terminal.
2. Calcium channels make the synaptic vesicles containing neurotransmitters fuse with the membrane and release neurotransmitters into the synaptic cleft.
3. Neurotransmitters bind to receptors on the postsynaptic neuron.
4. Those receptors open channels.
5. a. Excitatory neurotransmitters open sodium channels (more positive = more chance for AP)
b. Inhibitory neurotransmitters open chloride channels or potassium channels (more negative = less chance for AP)
6. Neurotransmitters get broken down by enzymes or reuptake
Lesson 6: The Addicted Brain
What are the four stages of addiction? What order do they come in?
1. Initiation – first time trying
2. Continuation – still using the drug
3. Cessation – stopping/trying to quit
4. Relapse – using again after quitting
How might our communities be improved if more people (and more health professionals) treated addiction like a disease and not a personal choice?
There would probably be less stigma around addiction, and people would be more likely to get treated and provide more support for people dealing with addiction from it not being a crime.
What is a conditioned stimulus? How do conditioned stimuli work to encourage addicts to use drugs?
An event that originally meant nothing, but after being paired with a sensation brings a response. Conditioned stimuli create cravings.
How is the reward pathway involved in drug addiction?
The drug hijacks the brain to continously send dopamine to create cravings and people to seek drugs.
How is the learning pathway involved in drug addiction?
When you get the positive sensation from using drugs, your learning pathway remembers that and continues to seek for that positive feeling again.
What are the roles of dopamine and glutamate in drug addiction?
Dopamine initiates and helps with the continuation of drug usage, while glutamate causes compulsion and cessation and relapsing.
Why do addicts show less dopamine in their brains than non-addicts?
The increased amount of dopamine from drug usage teaches the brain to adapt to the increased levels by changing the amount of dopamine receptors and the brains sensitivity to dopamine.
What are four events that can make relapse more likely?
1. Stress
2. Drug use
3. Conditioned stimuli
4. Withdrawal symptoms
What are the two main treatment options for addiction, and how can they help addicts to quit?
1. Medication - prevents “high” feeling, and treats withdrawal symptoms
2. Psychotherapy – Learning to avoid, prevent relapsing, resists cravings by strengthening brain connections