Characteristics of Life - The Big Ideas… Made of Cells Reproduce (sexually or asexually) Have DNA (genetic information) Grow & Develop Need/Use Energy (metabolism) Respond to Environment Maintain Homeostasis (constant internal environment) Change Over Time (evolve) Form Systems & Have Systems (related parts) Structure & Function are Related

Introduction to Human Body Systems

Organizational Levels Smallest Cells – 1st level of organization; basic unit of structure and function Tissues – A group of cells that perform that same function Types: Muscle, Connective, Nerve and Epithelial Organs – a group of tissues that perform a specific function Largest Organ Systems – a group of organs that work together to perform a specific function.

The Human Body Each organ system is dependent on other organ systems for the body to function properly. Nervous – Obtains and processes information from the body’s internal and external environment; directs most body functions brain, spinal cord, nerves Cardiovascular – Transports needed materials to body cells; removes wastes Heart, arteries, veins, blood cells

The Human body Digestive – breaks down food and absorbs the broken-down materials Mouth, stomach, small intestine, large intestine Respiratory – gets oxygen into the body; removes carbon dioxide Trachea (windpipe), lungs, diaphragm Muscular – enables the body to move Skeletal, smooth, cardiac

The Human body Skeletal – supports and protects the body; works with muscles to enable movement. Bones (Femur, Cranium, Ribs) Endocrine – produces chemicals called hormones that help control many body processes. Glands, stomach, pancreas, kidneys Excretory – removes wastes; helps regulate water in the body Kidneys, bladder, liver, large intestine

The Human Body Immune – fights disease / pathogens AS - Overview of Body Systems Immune – fights disease / pathogens Liver, lymph nodes, blood, thymus Integumentary (skin) – protects the body, keeps water inside and helps sense the external environment. Skin, hair, nails Reproductive – creates gametes & offspring; determines male and female characteristics Ovaries and uterus in females; testes in males

Transporting Oxygen Respiratory System – delivery of oxygen and removal of carbon dioxide Trachea – tube connecting the mouth to the lungs Alveoli – round sacs that make up the lungs where gases are exchanged. Moves oxygen from the air to the blood Moves carbon dioxide from the blood to the air Cardiovascular System – Carries oxygen from the lungs to the blood stream Arteries – tubes that carry oxygen enriched red blood cells from the lungs to other cells in the body Veins – carries oxygen depleted red blood cells to the lungs Muscular System – Enables air to enter and exit lungs Diaphragm – special muscle that contracts and shortens to pull/push air in and out of the lungs

Processing Food/Nutrients Digestive System – breaks down food into smaller substances to be used by body cells Mouth and stomach – begins to break down food Small intestine – completes the break down and absorbs the nutrients (through the villi) Large intestine – undigested food passes out of the body as waste Muscular – moves jaw to break down food & peristalsis Absorption of nutrients Enables you to swallow food / moves food along system With in the stomach – food is churned and squeezed, broken down into smaller particles. Cardiovascular – carries nutrients absorbed through the small intestine to the blood and then throughout the body.

Movement Muscles, Bones, Nerves… Muscles produce movement by contracting and shortening. Muscles are connected to and pull on your bones to move them. Nervous system uses the brain and nerves to direct your muscles and tell you when to move and how. Respiratory system brings oxygen to your muscles and removes carbon dioxide. Digestive system processes food and nutrients to fuel your muscles cells to keep them working properly. Organ Sytems AS - Overview of Body Systems