quiz 3 flashcards

Autonomic Nervous System (ANS)

• Involuntary system;

• regulates smooth, cardiac muscle, and glands.

• Uses 2 neurons: preganglionic and postganglionic

Sympathetic Division Origin

Preganglionic neurons originate in thoracic and lumbar spinal cord (T1-L2)

Sympathetic Axon Length

Short preganglionic and long postganglionic axons for fast, widespread responses.

Parasympathetic Function

Rest-and-digest response: decreases heart rate, increases digestion and salivation.

Neurotransmitter in ANS

Acetylcholine is released by all preganglionic neurons (both sympathetic and parasympathetic).

Somatic Nervous System

Voluntary control, targets skeletal muscles, uses one myelinated neuron.

Poliomyelitis

Viral disease that attacks motor neurons, causing paralysis.

Multiple Sclerosis (MS)

Autoimmune disease that damages the CNS myelin sheath, disrupting nerve signals.

Sensory Transduction

Process of converting a stimulus into an electrical signal by sensory receptors.

Superior Oblique Muscle

Moves the eye downward and laterally; innervated by CN IV.

Special Senses Nerves

Carried only by cranial nerves (not spinal nerves).

Olfaction Receptor Type

Uses neurons directly as receptors; they can regenerate.

Presbyopia

Age-related loss of lens flexibility; difficulty focusing on close objects.

Lens Flattening

Occurs when ciliary muscle relaxes and suspensory ligaments pull lens flat.

Accommodation

Process of changing lens shape to focus on near objects.

Rods vs. Cones

Rods detect light and dark (not color); cones detect color and detail.

Olfactory Cortex Location

Located in the temporal lobe.

Stapes

Middle ear bone that covers the oval window and transmits sound vibrations.

Crista Ampullaris

Receptor in semicircular canals that detects angular (rotational) movement.

Saccule

Vestibular receptor that detects vertical linear movement.

Foliate Papillae

Taste buds active in childhood; degenerate with age.

Sour Taste

Stimulated by hydrogen ions (H) from acidic foods.

Gustation

Sense of taste detected by taste buds.

Olfaction and Vision Pathways

Only special senses that bypass the brainstem and go directly to cortex.

2 neurons are:

preganglionic and postganglionic

preganglionic are…..

myelinated

postganglionic are…..

unmyelinated

Rods detect ……

light and dark (not color);

cones detect ……

color and detail