Human Anatomy and Body Systems

Levels of Organization Remember, the human body is organized in several levels, from the simplest to the most complex... Atoms – basic unit of matter Macromolecules – carbohydrates, lipids, proteins, DNA Organelles – specialized parts of the cell with a specific funtion Cells – the basic unit of life Tissues – clusters of cells performing a similar function (epithelial, connective, muscular, and neural) Organs – made of tissues that perform a specific function Organ Systems – groups of organs that perform a specific purpose in the human body ***The purpose of the 11 organ systems is for the human body to maintain homeostasis.

The 11 Human Body Systems -- nervous system -- urinary (excretory) system -- cardiovascular (circulatory) system -- endocrine system -- lymphatic (immune) system -- integumentary system -- respiratory system -- digestive system -- skeletal system -- muscular system -- reproductive system

Integumentary System Skin, Hair & Nails  Forms the external body covering  Protects deeper tissue from injury  Helps regulate body temperature

Skeletal System Bones, Joints, Cartilage & Ligaments  Protects and supports body organs  Provides muscle attachment for movement  Site of blood cell formation  Stores minerals

Muscular System Cardiac, Smooth & Skeletal  Produces movement  Pumps the heart  Movement of materials through digestive tract

Nervous System Brain, Spinal Cord, Nerves & Sensory Receptors  Fast acting Control System  Receives and interprets sensory input  Responds to internal and external change  Memory, emotions, cognition

Endocrine System Glands  Secretes hormones  Control / Regulates: Growth, Reproduction and Metabolism

Respiratory System Lungs, Nasal Passages, Pharynx, Larynx, Trachea Bronchi  Delivers oxygen; keeps blood supplied with oxygen  Removes carbon dioxide

Cardiovascular System Heart & Blood vessels  Transports oxygen, nutrients, hormones, carbon dioxide, waste

Lymphatic System Lymphatic vessels and Nodes  Returns body fluids to the bloodstream  Involved with immunity

Digestive System Esophagus, Stomach, Intestines  Breaks down foods for absorption of nutrients by the body  Eliminates indigestible material

Urinary System Kidneys and Bladder  Removes nitrogen-containing wastes from blood  Maintains acid-base balance  Regulates water and electrolytes

Reproductive System Male: Testes, Scrotum, Penis Females: Ovaries, Uterus, Vagina  Enables production of offspring