Human Anatomy and Physiology Lecture Notes

Introduction

• This is an introductory chapter in the Human Anatomy and Physiology course.
• Focuses on definitions and importance of understanding anatomy and physiology.
• Anatomy: Study of the structure of body parts and their relationships.
• Physiology: Study of the function of body parts.

Subdivisions of Anatomy

Gross (Macroscopic) Anatomy

• Regional Anatomy: Studies structures in a particular area (e.g., head, neck).
• System Anatomy: Focuses on one system (e.g., cardiovascular).
• Surface Anatomy: Studies superficial markings.

Microscopic Anatomy

• Cytology: Study of cell structure.
• Histology: Study of tissues and their functions.

Developmental Anatomy

• Focuses on anatomical/physiological development throughout life.
• Embryology: Studies development before birth.

Human Physiology

• More complex than anatomy.
• Subdivisions based on organ systems (e.g., renal, neurophysiology).
• Cell Physiology: Study of cell functions at chemical and molecular levels.

Complementarity of Structure and Function

• Anatomy and physiology are inseparable.
• Structure often reflects function (e.g., teeth structure and function).

Levels of Structural Organization

1. Chemical Level: Atoms, molecules, and organelles.
2. Cellular Level: Cells, the basic units of life.
3. Tissue Level: Groups of similar cells.
4. Organ Level: Contains two or more types of tissues.
5. Organ System Level: Organs working together.
6. Organismal Level: All organ systems combined.

Necessary Life Functions

• Maintaining Boundaries: Separation between internal and external environments.
• Movement: Includes movement of body parts and substances.
• Responsiveness: Ability to sense and respond to stimuli.
• Digestion: Breakdown and absorption of nutrients.
• Metabolism: Sum of all chemical reactions in the body.
• Excretion: Removal of wastes from metabolism and digestion.
• Reproduction: Cellular division for growth and repair.
• Growth: Increase in size or number of cells.

Survival Needs

• Nutrients: Essential for energy and cell building.
• Oxygen: Essential for energy release.
• Water: Most abundant chemical in the body.
• Normal Body Temperature: Necessary for chemical reactions.
• Appropriate Atmospheric Pressure: Required for breathing.

Homeostasis

• Ability to maintain stable internal conditions.
• Involves receptor, control center, and effector.
• Negative Feedback: Reduces effect of stimulus (e.g., body temperature regulation).
• Positive Feedback: Enhances stimulus (e.g., blood clotting).

Homeostatic Imbalance

• Can lead to diseases (e.g., diabetes, heart failure).
• Aging affects homeostatic control mechanisms.

Organ Systems Overview

• Integumentary System: Skin, hair, nails; protects against hazards.
• Skeletal System: Bones, cartilage; supports and protects.
• Muscular System: Muscles, tendons; movement and heat production.
• Nervous System: Brain, nerves; immediate response to stimuli.
• Endocrine System: Glands; regulates growth, reproduction.
• Cardiovascular System: Heart, blood vessels; transports nutrients.
• Lymphatic System: Lymph nodes, vessels; defends against infection.
• Respiratory System: Lungs, trachea; gas exchange.
• Digestive System: Stomach, intestines; processes food.
• Urinary System: Kidneys, bladder; eliminates waste.
• Reproductive System: Gonads; produces sex cells and hormones.

This concludes the first lecture on the introduction to anatomy and physiology, setting the stage for more detailed studies in future classes.