Human Physiology for Medical Students: Autonomic Nervous System & Nerve and Muscle

These flashcards cover important vocabulary terms and concepts from the lecture on human physiology, specifically focusing on the autonomic nervous system and nerve and muscle physiology.

Autonomic Nervous System (ANS)

Part of the nervous system that controls involuntary functions in the body, such as heart and gland activity.

Sympathetic Nervous System

Division of the ANS that arises from thoracic and upper lumbar spinal cord, responsible for the body's 'fight or flight' responses.

Parasympathetic Nervous System

Division of the ANS that arises from cranial and sacral regions of the spinal cord, responsible for 'rest and digest' activities.

Ganglion

A cluster of nerve cell bodies in the peripheral nervous system.

Preganglionic Fibers

Nerve fibers that transmit impulses from the central nervous system to a ganglion.

Postganglionic Fibers

Nerve fibers that transmit impulses from a ganglion to an effector organ.

Visceral Reflexes

Reflex actions that involve the internal organs controlled by the ANS.

Action Potential (AP)

A rapid rise and fall in membrane potential that propagates along nerve and muscle fibers.

Thermoregulation

The process of maintaining body temperature within a tolerable range.

Skeletal Muscle

Type of striated muscle that is under voluntary control and facilitates movement of the skeleton.

Smooth Muscle

Involuntary, non-striated muscle found in walls of internal organs and blood vessels.

Neuromuscular Junction

The site where a motor neuron stimulates a muscle fiber, facilitating muscle contraction.

Myelin Sheath

An insulating layer around nerve fibers that speeds up nerve conduction.

Calmodulin

A calcium-binding messenger protein that plays a key role in smooth muscle contraction.

Acetylcholine

A neurotransmitter released at neuromuscular junctions that initiates muscle contractions.

Treppe Phenomenon

The 'staircase effect', where increased strength of muscle contractions occurs with successive stimuli.

Rigor Mortis

The stiffening of muscles post-mortem due to depletion of ATP.

Donnan Effect

The effect on the distribution of diffusible ions when a non-diffusible ion is present.

Osmosis

The movement of water across a semipermeable membrane from an area of low solute concentration to high solute concentration.

Facilitated Diffusion

Passive transport of molecules across a cell membrane via a protein channel.