Overview
The lecture introduces the basics of Anatomy & Physiology (A&P), explains the organization of the human body, and covers major organ systems and their functions.
Introduction to Anatomy & Physiology
- Anatomy is the study of body structure; physiology is the study of body function.
- A&P are closely related because structure determines function and vice versa.
- Understanding A&P is essential for health professionals.
Levels of Organization in the Human Body
- The human body is organized from atoms → molecules → cells → tissues → organs → organ systems → organism.
- Cells are the basic unit of life; tissues are groups of similar cells performing a function.
- Organs are structures composed of different tissues; organ systems are groups of organs working together.
Major Organ Systems
- Integumentary System: Protects the body and regulates temperature (skin, hair, nails).
- Skeletal System: Provides structure, support, and protection; enables movement (bones, joints).
- Muscular System: Produces body movement, maintains posture, and generates heat (muscles).
- Nervous System: Controls body functions through electrical impulses (brain, spinal cord, nerves).
- Endocrine System: Regulates body activities using hormones (glands).
- Cardiovascular System: Transports nutrients, gases, and wastes (heart, blood vessels).
- Lymphatic/Immune System: Defends against infection and returns fluid to blood (lymph nodes, spleen).
- Respiratory System: Exchanges gases between air and blood (lungs).
- Digestive System: Breaks down food, absorbs nutrients, eliminates waste (stomach, intestines).
- Urinary System: Removes waste from the blood; regulates water balance (kidneys).
- Reproductive System: Produces offspring (ovaries, testes).
Homeostasis
- Homeostasis is the maintenance of a stable internal environment.
- The body uses feedback mechanisms, mainly negative feedback, to maintain homeostasis.
Key Terms & Definitions
- Anatomy — study of body structures.
- Physiology — study of body functions.
- Cell — smallest unit of life.
- Tissue — group of similar cells with a common function.
- Organ — structure made of different tissues working together.
- Organ system — group of organs performing related functions.
- Homeostasis — maintaining a stable internal condition.
- Negative feedback — process that reverses a change to maintain balance.
Action Items / Next Steps
- Review the major organ systems and their primary functions.
- Read assigned textbook chapters on body organization and homeostasis.