Introduction to Anatomy and Physiology

Characteristics of Life Anatomy and Physiology are important components of biology --- the study of life. So, when is something considered living? To differentiate between living and nonliving things, scientists often refer to the Characteristics of Life.

Characteristics of Life Responses to a Stimulus Conduct Signals Grows Respires Digests Foods Absorbs Nutrients Secretes Substances Excretes Wastes Circulates Materials Capable of Reproduction

Levels of Organization The 11 major systems of the human body that keep us alive: 1. integumentary 7. circulatory 2. skeletal 8. respiratory 3. muscular 9. digestive 4. nervous 10. urinary 5. endocrine 11. reproductive 6. lymphatic/immune

Integumenary System Structures: Functions: - Skin, hair, sweat and oil glands Functions: Forms the external body covering Protects deeper tissues from injury Involved in vitamin D synthesis Prevents desiccation, heat loss, and pathogen entry Has pain and pressure receptors

Skeletal System Structures: Functions: The 206 bones of the human body Protects and supports body organs Provides a framework that muscles can use to create movement Hemopoiesis (synthesis of blood cells) Mineral storage

Muscular System Structures: Functions: The 600+ muscles of the body Locomotion Maintaining posture Thermogenesis (generation of heat)

Nervous System Structures: Functions: Brain, spinal cord, and peripheral nerves Functions: The control system of the body Monitoring of the internal and external environment and responding to those changes when necessary.

Endocrine System Structures: Functions: Hormone-secreting glands Long-term control system of the body Makes hormones that regulate growth, reproduction, and nutrient use among other things.

Lymphatic/Immune System Structures: Lymph nodes, Spleen, Thymus, White Blood Cells Functions: Returning “leaked” fluid back to the bloodstream Disposal of debris Attacking and resisting foreign invaders

Circulatory System Structures: Functions: Heart, Blood vessels (arteries, veins, and capillaries) Functions: The heart pumps blood thru the blood vessels. Blood transports nutrients, gases, wastes, hormones, and body heat.

Respiratory System Structures: Functions: Nasal cavity, pharynx, trachea, bronchi, lungs Functions: Constantly supply the blood with O2, and remove CO2

Digestive System Structures: Functions: Buccal cavity, esophagus, stomach, small intestine, large intestine, rectum, salivary glands, pancreas, liver, gallbladder Functions: Ingestion and subsequent breakdown of food into absorbable units that will enter the blood for distribution to the body’s cells

Urinary System Structures: Functions: Kidneys, ureters, urinary bladder, urethra Functions: Removal of nitrogenous wastes Regulation of body’s levels of water and electrolytes

Reproductive System Structures: Functions: Male: Female: Testes, scrotum, epididymis, vas deferens, urethra, prostate gland, seminal vesicles, penis Female: Ovary, uterine tube, uterus, cervix, vagina, mammary glands Functions: Production of offspring