Anatomy and Physiology I: Complete Semester 1 Study Notes

Anatomy explains body structure; physiology explains how those structures function. Nursing students need both because assessment, symptoms, procedures, and clinical decisions all depend on understanding normal structure and function.

1. Anatomical Language

The standard anatomical position is standing upright, facing forward, arms at the sides with palms forward. Directional terms include superior/inferior, anterior/posterior, medial/lateral, proximal/distal, superficial/deep, and ipsilateral/contralateral. Major planes are sagittal, frontal, and transverse.

2. Body Cavities and Regions

The cranial cavity contains the brain; the vertebral cavity contains the spinal cord; the thoracic cavity contains the lungs and mediastinal structures; and the abdominopelvic cavity contains major digestive, urinary, and reproductive organs. Abdominal quadrants and nine-region systems help describe pain and organ location.

3. Levels of Organization

The human body is organized from chemical level to cells, tissues, organs, organ systems, and the whole organism. Four major tissue types are epithelial, connective, muscle, and nervous tissue.

4. Homeostasis

Homeostasis is the maintenance of a relatively stable internal environment. A feedback system usually contains a receptor, control center, and effector. Negative feedback reverses a change and is common in temperature and blood glucose regulation. Positive feedback amplifies a process, such as uterine contractions during labor.

5. Cells and Membranes

Important cell structures include the plasma membrane, nucleus, mitochondria, ribosomes, endoplasmic reticulum, Golgi apparatus, and lysosomes. Diffusion moves particles down a concentration gradient. Osmosis is movement of water across a selectively permeable membrane. Active transport requires energy.

6. Skin

The integumentary system protects against injury and infection, helps regulate temperature, provides sensation, and reduces fluid loss. The epidermis is superficial; the dermis contains blood vessels, nerves, glands, and hair follicles.

7. Skeletal System

The skeleton supports the body, protects organs, enables movement, stores minerals, and contains marrow for blood cell formation. The axial skeleton includes skull, vertebral column, and thoracic cage. The appendicular skeleton includes limb bones and girdles. Bone types include long, short, flat, irregular, and sesamoid bones.

8. Muscular System

Skeletal muscle is voluntary and moves bones. Cardiac muscle is found in the heart. Smooth muscle is involuntary and found in hollow organs and vessels. Muscle contraction depends on nerve stimulation, calcium, and energy from ATP.

9. Blood and Cardiovascular Basics

Blood contains plasma, red blood cells, white blood cells, and platelets. Red cells carry oxygen using hemoglobin. The heart has four chambers and valves that maintain one-way blood flow. The right heart sends blood to the lungs; the left heart sends oxygenated blood to the body.

10. Respiratory and Digestive Overview

The respiratory system conducts air to the alveoli, where oxygen and carbon dioxide are exchanged. The digestive system mechanically and chemically processes food, absorbs nutrients, and eliminates waste. Major organs include mouth, esophagus, stomach, small intestine, large intestine, liver, gallbladder, and pancreas.

Clinical Link

When a patient’s pulse, breathing, blood pressure, movement, sensation, or abdominal findings change, anatomy and physiology help explain what may be happening and what the nurse should assess next.