Chapter 3 Notes AP Tips

Know the basic structure of a neuron  Dendrites receive information from adjacent neurons; process incoming chemicals and propel info to the nucleus  The axon is the neural fiber that transmits info from the soma to the other end of the neuron; encased by myelin, a fatty substance that protects info stored inside the axon  The axon terminal is the ending part of the neuron that releases information

Know the types of neurons  Sensory (afferent) neurons transmit info from the spinal cord to the brain; they help our brains register sensory information  Motor (efferent) neurons transmit info from the brain to muscles and glands  S.A.M.E.

 Be familiar with the process of neural transmission—specifically, the all-or- none principle, and know which ions enter and exit during polarization and depolarization.

Order of events in the firing of a neuron  Polarization  Resting potential  Depolarization  Action potential  Threshold  All-or-none principle  Refractory period

Polarization  Negatively charged chloride ions exist within the axon, resulting in a negative charge.

Resting potential  Negatively charged ions wait for stimulation within the axon. The neuron is said to be inactive and is waiting for another action potential.

Depolarization  When stimulated, the channels along the axon allow positively charged sodium and potassium ions to enter. This causes sodium and potassium channels to open, thus propelling the electrochemical process down the axon.

Action potential  A change in the balance of the overall charge of the neuron causes the electrochemical signal to travel ( it is fired) along the axon.

Threshold  A point of excitation on the neuron that must be reached for an action potential to occur

All-or-none principle  Once the threshold is reached, the neuron will fire at full strength. If the threshold is not reached, the neuron will not fire.

Refractory period  The period after a neuron fires, at which time it is less susceptible to stimulation from other neurons. The neuron must recharge itself electrically until it reaches polarization. Once this occurs, the neuron is ready to fire again.

Know about specific neurotransmitters and the resulting effects of an excess or a deficiency.  Acetylcholine  Dopamine  Serotonin  GABA  Norepinephrine  Glutamate

Know the organization of the nervous system  Central Nervous System  Peripheral Nervous System  Autonomic Nervous System

Central Nervous System (CNS)  Responsible for processing and distributing information throughout the body

Brain  Responsible for cognitive functioning

Spinal Cord  Responsible for transmitting information throughout the body.

Peripheral Nervous System (PNS)  Responsible for voluntary movement and regulation of vital processes.

Somatic Nervous System  Responsible for voluntary movement

Autonomic Nervous System  Regulation of vital human functioning (breathing, digestion, heartbeat, etc)

Sympathetic Nervous System  Spends reserved energy

Parasympathetic Nervous System  Restores and repairs spend energy

Know about the 4 brain lobes  Frontal lobe: responsible for controlling inhibitions, short-term memory, reasoning, and planning for the future  Parietal lobe: responsible for receiving and combining tactile (touch) stimuli from all over the body to allow the formation of a single concept.

 Occipital lobe: responsible for processing visual stimuli, as well as maintaining balance  Temporal lobe: responsible for processing auditory stimuli

Be able to identify the functions of Broca’s and Wernicke’s areas.  Broca’s area: responsible for transferring thoughts into audible spoken words  Wernicke’s area: responsible for transforming spoken words into thoughts

Know the location and functions of brain structures  Complete table

Know the area of the brain responsible for hunger.  Hypothalamus

Know how psychologists look into the brain.  EEG: electrodes are placed on the scalp to measure the brain’s electrical activity  CT or CAT Scan: produces a 2-dim image based on x-rays taken around a single axis  MRI: uses a large magnetic field to reconstruct the image within the body/brain

 fMRI: measures neural activity within the brain  PET scan: uses radioactive liquid to measure metabolic and glucose processing (3-dim view)

Know the major glands, their hormones, and their functions  Complete table