Transcript What is resting membrane potential, how is it created and maintained?

What is resting membrane potential,
how is it created and maintained?
• -Separation of charges (inside more negative)
• -Caused by differences in permeability
between Na+ and K+
– K+ allowed to leave, and Na+ can not enter the
cell
• Maintained by Na/K/ATPase pump
What is an action potential? Graph and
describe different parts of process
• --Conduction of electric current
• 1. If above threshold, voltage gated channels
open = rapid depolarization
• 2. Action potential ends; K+ channels open
leading to hyperpolarization
• 3.
Explain transmission of a nerve signal
across a synapse
Why are impulses transmitted more
quickly down a myelinated axon than
an unmyelinated axon.
• Myelin produces saltatory conduction, where
action potentials are only generated at the
nodes of Ranvier, rather than every adjacent
part of the axon.
• Occurs because myelin insulates the current
and does not allow it to leak out
What are the functions performed by the three
types of neurons? Describe the structure and
functions of the three parts of a neuron
• Sensory Neurons: take info from sensory receptors
to the CNS
• Interneurons: Receive input from all sensory and
other interneurons and communicate with motor
neurons
• Motor: Takes info from CNS to rest of body
• Cell body: contains nucleus and other organelles
(where neurotransmitters are built)
• Dendrites: short extensions that receive signals
• Axon: usually long that conducts the nerve impulse
Name Major Parts of brain and give
function for each part
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Cerebrum: Integrates and command center
Hypothalamus: Helps maintain homeostasis
Thalamus: Receives sensory input
Cerebellum: Muscle control
Pons: Bridge between cerebellum and CNS
Medulla Oblongata: breathing and heart rate
Compare two divisions of Autonomic
Nervous System
• Sympathetic: Fight or Flight
• Parasympathetic: Rest and Digest
Describe various types of Memory
• Short-term
• Episodic: (persons and events that you
remember)
• Semantic (numbers and words)
• Skill memory (performing motor activities)
• Long-term
Describe structure of taste bud and
explain how a taste cell functions
• In the wall of a papillae containing a receptor
for a specific type of taste (sweet, sour, salty,
bitter and umami)
• Chemicals in food bind to the receptors,
generating a graded potential, leading to
action potential (nerve signal that travels to
the brain)
– Gustatory cortex where taste is interpreted