Anatomy & Physiology Exam 3: Short Answer Focus Study Guide

Chapter 14: The Peripheral Nervous System

Cranial Nerves: Names, Fiber Types, Functions, and Exits

The cranial nerves are twelve pairs of nerves that emerge directly from the brain. Each has a specific name, fiber type (sensory, motor, or both), primary function, and exit point from the skull.

• Names: Olfactory (I), Optic (II), Oculomotor (III), Trochlear (IV), Trigeminal (V), Abducens (VI), Facial (VII), Vestibulocochlear (VIII), Glossopharyngeal (IX), Vagus (X), Accessory (XI), Hypoglossal (XII)

• Fiber Types: Sensory, Motor, or Both (Mixed)

• Functions: Include smell, vision, eye movement, facial sensation, hearing, taste, swallowing, and more.

• Exits: Each nerve exits the cranial cavity through specific foramina (e.g., optic canal, jugular foramen).

Example: The Facial nerve (VII) is a mixed nerve responsible for facial expression, taste from the anterior 2/3 of the tongue, and exits via the stylomastoid foramen.

Innervation of the Appendicular Skeleton: Motor and Cutaneous Compartments

Peripheral nerves innervate specific muscle compartments (motor) and skin regions (cutaneous) in the limbs. Understanding these patterns is essential for diagnosing nerve injuries.

• Motor Innervation: Each compartment (e.g., anterior thigh, posterior arm) is supplied by specific nerves.

• Cutaneous Innervation: Sensory nerves supply defined skin areas (dermatomes).

• Example: The femoral nerve supplies the anterior thigh muscles and the skin over the anterior thigh.

Additional info: Figures 14.10 and 14.13 typically illustrate these innervation patterns.

Spinal Nerve Origins of Peripheral Nerves

Peripheral nerves are formed from specific spinal nerve roots. Knowing their origins helps localize lesions.

• Example: The femoral nerve arises from spinal nerves L2-L4.

• Other Examples: The sciatic nerve arises from L4-S3; the radial nerve from C5-T1.

Chapter 15: The Autonomic Nervous System

Comparison of Parasympathetic and Sympathetic Divisions

The autonomic nervous system (ANS) has two main divisions with distinct anatomical and functional characteristics.

Feature	Sympathetic	Parasympathetic
Origin	Thoracolumbar (T1-L2)	Craniosacral (CN III, VII, IX, X; S2-S4)
Ganglia Location	Near spinal cord (sympathetic chain)	Near or in target organs
Neurotransmitter (Postganglionic)	Norepinephrine	Acetylcholine
General Function	"Fight or flight" (increases HR, dilates pupils)	"Rest and digest" (decreases HR, stimulates digestion)

Additional info: Table 15.1 typically summarizes these differences.

Chapter 16: The Special Senses

Changes in the Eye for Close and Distant Vision

The eye adjusts to focus on objects at different distances through accommodation, pupil constriction, and convergence.

• Close Vision: Ciliary muscles contract, lens becomes more convex, pupils constrict, eyes converge.

• Distant Vision: Ciliary muscles relax, lens flattens, pupils dilate, eyes diverge.

Near vs. Far Sightedness:

• Nearsighted (Myopia): Image focuses in front of the retina; distant objects are blurry.

• Farsighted (Hyperopia): Image focuses behind the retina; close objects are blurry.

Additional info: Clinical applications may include corrective lenses for each condition.

Visual Pathway and Visual Fields

Light signals travel from the retina through the optic nerves, cross at the optic chiasm, and continue to the visual cortex.

• Pathway: Retina → Optic nerve → Optic chiasm → Optic tract → Lateral geniculate nucleus → Visual cortex

• Visual Fields: Each half of the visual field is processed by the opposite side of the brain.

Overview of Sound Wave Transmission

Sound waves are transmitted through the ear via a series of mechanical and neural steps.

• Sound waves enter the external ear, vibrate the tympanic membrane, move the ossicles, and create waves in the cochlear fluid, stimulating hair cells.

• Hair cells convert mechanical energy into nerve impulses sent to the brain.

Conduction vs. Sensory Deafness

• Conduction Deafness: Caused by problems in the outer or middle ear (e.g., earwax, ossicle damage).

• Sensory (Sensorineural) Deafness: Caused by damage to the inner ear or auditory nerve.

Chapter 17: The Endocrine System

Table 17.1: Major Endocrine Organs and Their Hormones

The endocrine system consists of glands that secrete hormones to regulate body functions.

Gland	Hormone(s)	Main Function(s)
Pituitary	GH, TSH, ACTH, LH, FSH, PRL, ADH, Oxytocin	Growth, metabolism, reproduction, water balance
Thyroid	Thyroxine (T4), Triiodothyronine (T3), Calcitonin	Metabolism, calcium regulation
Adrenal	Cortisol, Aldosterone, Epinephrine	Stress response, electrolyte balance
Pancreas	Insulin, Glucagon	Blood glucose regulation
Ovaries/Testes	Estrogen, Progesterone, Testosterone	Reproduction

Additional info: Table 17.1 summarizes the major glands, hormones, and their functions.

Chapter 18: Blood

Table 18.1: Formed Elements of Blood

Blood contains three main types of formed elements, each with distinct functions.

Element	Main Function
Erythrocytes (RBCs)	Transport oxygen and carbon dioxide
Leukocytes (WBCs)	Defend against pathogens
Platelets (Thrombocytes)	Blood clotting

Additional info: Description and development/lifespan are not required for this exam.

Chapter 19: The Heart

Oxygenation of Blood in Heart Structures

Blood in the heart is either oxygenated or deoxygenated, depending on its location in the cardiac cycle.

• Deoxygenated Blood: Right atrium, right ventricle, pulmonary arteries

• Oxygenated Blood: Left atrium, left ventricle, pulmonary veins, aorta

Example: Blood entering the right atrium from the body is deoxygenated; blood leaving the left ventricle to the aorta is oxygenated.

Chapter 21: The Lymphatic and Immune Systems

Functions of Lymphatic Organs (Fig 21.8)

Lymphatic organs play key roles in immune defense and fluid balance.

Organ	Main Function
Lymph Nodes	Filter lymph, house lymphocytes
Spleen	Filters blood, recycles RBCs, immune surveillance
Thymus	T cell maturation
Tonsils	Trap pathogens entering through mouth/nose

Additional info: Figure 21.8 typically labels these organs and summarizes their functions.