Lecture- The Nervous System, Part 1: Crash Course Anatomy & Physiology

Nervous System

Controls organs and physiological responses in organisms.

Sensory Input

Detection of stimuli through sensory receptors.

Integration

Processing sensory information to determine response.

Motor Output

Response action executed by muscles or glands.

Central Nervous System (CNS)

Brain and spinal cord; main control center.

Peripheral Nervous System (PNS)

Nerves branching from CNS to the body.

Afferent Division

Conducts sensory information to the brain.

Efferent Division

Sends commands from brain to muscles and glands.

Somatic Nervous System

Controls voluntary movements of skeletal muscles.

Autonomic Nervous System

Manages involuntary actions like heartbeat and digestion.

Sympathetic Division

Activates fight or flight response.

Parasympathetic Division

Calms the body after activation.

Neurons

Main signaling cells of the nervous system.

Neuroglia (Glial Cells)

Support and protect neurons; half brain's mass.

Astrocytes

Anchor neurons to blood supply; regulate material exchange.

Microglial Cells

Provide immune defense in the CNS.

Ependymal Cells

Line brain cavities; produce cerebrospinal fluid.

Oligodendrocytes

Insulate neurons with myelin sheath in CNS.

Satellite Cells

Support neuron cell bodies in PNS.

Schwann Cells

Insulate axons in the peripheral nervous system.

Multipolar Neurons

Most common type; multiple dendrites and one axon.

Unipolar Neurons

One process; primarily in sensory receptors.

Bipolar Neurons

Two processes; found in special sensory organs.

Interneurons

Connect sensory and motor neurons; mostly multipolar.