Exam 3 Physiology

What are the two primary divisions of the nervous system?

Central Nervous System (CNS) and Peripheral Nervous System (PNS)

What are the components of the CNS?

Brain and spinal cord.

What are the components of the PNS?

Cranial nerves and 31 pairs of spinal nerves.

The is the ___ unit of the nervous system.

Neurons, functional.

What are the 5 types of neuroglial cells?

Oligodendrocytes, Microglia, Astrocytes, Ependymal cells, Schwann cells.

What is the function of oligodendrocytes?

Form myelin in CNS.

What is the function of Microglia?

Immune function; protect the brain from damage and infection.

What is the function of Astrocytes?

Form blood brain barrier.

What is the function of Ependymal cells?

Produce cerebral spinal fluid.

What is the function of Schwann cells?

Produce myelin in PNS.

What are the 4 parts of a neuron?

Cell body, dendrites, axon, axon terminals.

What is the function of the cell body (soma) in a neuron?

Responsible for maintaining the neuron's structure and carrying out metabolic functions (contains nucleus).

What is the function of dendrites in a neuron?

Receive incoming signals from other neurons.

What is the function of the Axon in a neuron?

It carries messages away from the cell body.

What is the function of the Axon terminal in a neuron?

Forms a synapse with another neuron or target cell, containing vesicles filled with neurotransmitters.

Define Nuclei.

Group of similar neurons within the CNS.

Define Ganglia.

Group of similar neurons within the PNS.

What does sensory (afferent) refer to?

Sends information to the brain.

What does motor (efferent) refer to?

Sends information to the body.

What nerves can repair themselves to some extent?

Peripheral nerves (nerves outside the brain and spinal cord).

What nerves cannot be repaired?

CNS nerves (brain and spinal cord).

What is the blood-brain barrier?

A highly selective and semipermeable membrane that separates circulating blood from the brain.

How is the blood-brain barrier formed?

Formed by tightly connected endothelial cells lining blood vessels in the brain.

What is the function of the blood-brain barrier?

Protects the brain from harmful substances and pathogens.

Describe the maintenance of resting membrane potential.

Maintained by Na+ and K+ pumps, creating a negative charge inside the cell.

What is frequency in relation to action potentials?

Number of action potentials that occur.

What is amplitude in relation to action potentials?

Size or magnitude of electrical signals.

What is conduction rate in relation to action potentials?

Speed at which an action potential travels down an axon.

What is saltatory conduction?

'Leaping' of action potential from node to node.

What neurotransmitter did Otto Loewi discover?

Acetylcholine (ACh).

How important was Otto Loewi's discovery?

Significant because it showed that the nervous system communicates both electrically and chemically.

What is the role of acetylcholine esterase?

Enzyme that breaks down acetylcholine in the synaptic cleft.

What is the role of glycine in the brain?

An inhibitory neurotransmitter involved in motor control and pain perception.

What is the role of GABA in the brain?

Inhibitory neurotransmitter that helps regulate neuronal activity.

What does synaptic plasticity refer to?

The strengthening of synapses to encode memories and information.

Long-term potentiation is involved in __ formation.

Memory formation.

What does 'circuit' mean in the brain?

Group of interconnected neurons that work together to perform specific functions.

What is the function of the Medulla Oblongata?

Controls autonomic functions of internal organs.

What is the function of the Cerebellum?

Controls basic and skilled movements.

What is the function of the Pons?

Connects cerebellum and spinal cord with higher brain centers.

What is the function of the Midbrain?

Relays visual and auditory inputs.

What is the function of the Thalamus?

Processes and transfers sensory input to higher brain areas.

What is the function of the Hypothalamus?

Controls the endocrine system by connecting to the pineal gland.

What is the function of the Limbic system?

Emotions and basic patterns of behavior.

What is the function of the Cerebrum?

Coordinates movement, decision-making, and produces thought and speech.

What are the 5 lobes of the cerebrum?

Frontal, parietal, temporal, occipital lobe, and insula.

What is the function of the frontal lobe?

Voluntary control of muscles/movement, speech, and personality.

What is the function of the parietal lobe?

Interpretation of sensations and language.

What is the function of the temporal lobe?

Interpretation of auditory sensations and memory storage.

What is the function of the occipital lobe?

Visual integration and perception.

What is the function of the insula?

Memory and sensation of pain.

What is the function of Broca's area?

Produces language.

What is the function of Wernicke's area?

Interprets language by receiving auditory and visual input.

What are some functions of the limbic system?

Learning, memory, emotions, and hormonal regulation.

What region of the brain regulates the limbic system and autonomic functions?

Hypothalamus.

What is the reticular formation responsible for?

Tuning out unimportant sensory stimulation when sleeping.

What are the basic functions of the autonomic nervous system (ANS)?

Regulates autonomic functions such as heart rate and blood vessels.

Does the ANS possess motor, sensory, or both fibers?

Contains both motor and sensory fibers.

What two divisions comprise the ANS?

Sympathetic and parasympathetic divisions.

Preganglionic fibers of the sympathetic division originate in __ regions.

Thoracolumbar regions.

Preganglionic fibers of the parasympathetic division originate in and regions.

CNS and Craniosacral.

Describe the sympathetic division.

Activates the body to deal with threats through norepinephrine and epinephrine.

Describe the parasympathetic division.

'Rest and Digest' system that slows heart rate and increases digestive activity.

Sympathetic effect on the heart?

Increases heart rate.

Parasympathetic effect on the heart?

Decreases heart rate.

Sympathetic effect on the pupil?

Dilates pupil.

Parasympathetic effect on the pupil?

Constricts pupil.

Sympathetic effect on the digestive system?

Inhibits digestion.

Parasympathetic effect on the digestive system?

Stimulates digestion.

Sympathetic effect on the lungs?

Increases respiratory rate.

Parasympathetic effect on the lungs?

Decreases respiratory rate.

Sympathetic effect on the blood vessels?

Constriction of blood vessels.

Parasympathetic effect on the blood vessels?

Dilation of blood vessels.

Sympathetic effect on the bladder?

Relaxes bladder muscles.

Parasympathetic effect on the bladder?

Contracts bladder muscles.

Sympathetic effect on the adrenal gland?

Causes secretion of epinephrine and norepinephrine.

Parasympathetic effect on the adrenal gland?

No effect.