A&P1 Exam4

What do dendrites do in a neuron?

Bring information into the soma.

What is the function of the soma in a neuron?

Contains the nucleus and integrates signals.

What is the role of the axon?

Takes information away from the soma.

What type of cells produce myelin in the PNS?

Schwann cells.

Who produces myelin in the CNS?

Oligodendrocytes.

What is myelin composed of?

Myelin is made up of lipids and proteins.

What is the primary purpose of myelin?

Acts as insulation to speed up signal transmission along the axon.

What ion influx occurs during depolarization?

Na+ (sodium) influx.

What ion efflux occurs during repolarization?

K+ (potassium) efflux.

Define depolarization.

Membrane potential becomes less negative.

What occurs during repolarization?

Membrane potential returns to resting state.

What is an action potential?

A rapid change in membrane potential that propagates along the axon.

What is the threshold in neural signaling?

Minimum level of depolarization required to trigger an action potential.

What are local potentials?

Small changes in membrane potential that can summate to reach the threshold.

Where does the spinal cord end?

Around the L1-L2 vertebral level.

What are the three layers of the meninges?

Dura Mater, Arachnoid Mater, Pia Mater.

What separates the left and right hemispheres of the brain?

Longitudinal fissure.

What are gyri and sulci in the brain?

Gyri are ridges and sulci are grooves on the surface of the brain.

What is the function of Broca's area?

Involved in speech production.

Where is Wernicke's area located and what is its function?

Located in the temporal lobe; involved in understanding language.

Which part of the brain is responsible for planning?

Frontal lobe.

Which lobe is primarily responsible for vision?

Occipital lobe.

What role does the hippocampus play in the brain?

Memory and learning.

What does the limbic system regulate?

Emotions.

What is the function of the cerebellum?

Balance.

What is the sympathetic nervous system responsible for?

Preparing the body for action (Fight-or-Flight).

What does the parasympathetic nervous system promote?

Relaxation and digestion (Rest and Digest).

What is the function of sensory (afferent) neurons?

Carries signals to the CNS.

What do motor (efferent) neurons do?

Carries signals from the CNS to muscles or glands.

Give examples of neurotransmitters and their functions.

GABA (inhibitory), Glutamate (excitatory).

What enzyme breaks down monoamines?

MAO (Monoamine Oxidase).

What do MAOIs do?

Inhibit MAO, increasing monoamine levels in the synapse.

What is cerebrospinal fluid (CSF) and its functions?

Circulates through ventricles and subarachnoid space, made in the choroid plexus, reabsorbed into the bloodstream.

What is the cervical plexus responsible for?

Phrenic nerve (diaphragm control).

What are examples of important reflexes?

Stretch reflex, withdrawal reflex, and reciprocal inhibition.

What does the brain stem include?

Midbrain, pons, and medulla oblongata; responsible for basic life functions.

What are the components of the limbic system?

Amygdala, hippocampus, thalamus, hypothalamus, basal ganglia, cingulate gyrus.

What are the phases of sleep?

NREM (Stages 1-3) and REM sleep.

What characterizes REM sleep?

Rapid eye movement, dreaming, and muscle atonia.

What do cranial nerves control?

Sensory and motor functions of the head and neck.