13.2 Human Body Systems

11 Body Systems ( We won’t cover all of them) Although the body can be divided into 11 different organ systems, all of the systems are interconnected with each other 11 Systems: Integumentary, Skeletal, Muscular, Nervous, Circulatory, Respiratory, Excretory, Digestive, Endocrine, Reproductive, Immune

Integumentary system ( skin) 2 layers: epidermis and dermis Functions: temperature regulation, vitamin production, protection, senses Hair- keratin, sebaceous glands to lubricate/ protect

Skeletal system Functions- support, protection, blood cell formation, reservoir for minerals, movement Axial system- skull, vertebrate, ribs, sternum Appendicular- shoulders, arms, hips, legs Compact bone- dense, tough, strong Spongy bone- lightweight Osteocyte- living bone cells

Muscular system 3 types of muscle tissue: – smooth: no striations, one nucleus per cell – skeletal: many nuclei, striations – cardiac: one nucleus per cell, striations

Nervous system Neuron- nerve cell consisting of 3 parts: dendrite, cell body, axon Neurotransmitter- chemical that transfers electrical impulse from one cell to another Synapse- gap between neurons and other cells

Circulatory system Functions: transport, temperature control 4 chambered heart: 2 atria, 2 ventricles Closed circuit, double loop Red blood cell- carries oxygen White blood cell- fights infection Artery- carries blood away from heart Vein – Carries blood towards heart Capillary- smallest blood vessel where exchange of gases and nutrients, into cells, occur

Respiratory System Air enters through mouth, past larynx ( voice box/ adam’s apple), trachea, L and R Bronchi, then to alveoli Alveoli are the site of gas exchange ( oxygen and carbon dioxide) Diaphragm- special muscle in mammals that, along with rib muscles, cause movement of air in and out of lungs

Excretory System Kidneys filter waste from blood Waste then moves to bladder and awaits signal to empty

Digestive System Mechanical digestion- chewing Chemical digestion- chemicals ( enzymes) are added to speed up chemical breakdown of food Peristalsis- muscular movement of food through digestive system Path: esophagus, stomach, small intestine, large intestine

We didn’t cover all of them!