Human Anatomy and Body Systems

The Digestive System Purpose: to break down food and absorb nutrients Major Organs and their Functions: Mouth – to chew and grind up food -- (salivary glands)saliva also begins the chemical breakdown Esophagus – pipe connecting mouth to stomach Stomach – secretes an extraordinarily strong acid leads to breakdown of food

Pancreas – produces insulin that regulates blood sugar Liver – produces bile, which breaks down fats in foods Gallbladder – stores bile Small Intestine – after digestion is complete, the nutrients are absorbed into the bloodstream Large Intestine – removes excess water from waste and moves it to be excreted

The Digestive System

Interactions – Working with Other Systems Circulatory: blood absorbs and delivers the digested nutrients to the cells Muscular: control the contractions of many of the digestive organ muscles to pass food along Nervous: hypothalamus maintains homeostasis by triggering appetite (stomach growling),

The Circulatory System Purpose: to deliver oxygenated blood to the various cells and organ systems in your body so they can undergo cellular respiration Major Organs and Their Functions Heart – the major muscle of the circulatory system -- pumps blood through its four chambers Arteries – carry blood away from the heart and to of the body Veins – carry blood back to the heart away from the body Capillaries – smallest blood vessels

Blood – the cells that flow through the circulatory system -- white, red, and platelets Spleen – helps to filter out toxins in the blood, removes worn out blood cells, produces white blood cells

Image of the Circulatory System

Interactions – Working with Other Systems Respiratory: deliver O ₂ from lungs to cells and drop off CO ₂ from cells to lungs Digestive: absorb and deliver digested nutrients to cells Excretory: kidneys filter cellular waste out of blood for removal Immune: transports WBC’s throughout body to fight disease Nervous: brain controls heartbeat Endocrine: transports hormones

The Nervous System Purpose: to coordinate the body’s response to changes in its internal and external environment(homeostasis) Senses and Responds to the environment Major Organs and Their Functions Brain – control center of the body, where all processes are relayed through Spinal Cord – sends instructions from the brain to the rest of the body and vice versa -- any organism with a major nerve cord is classified as a chordate Nerves – conduct impulses to muscle cells throughout the body

Diagram of a Nerve Cell

Interactions - Working with Other Systems Controls all other systems Muscular —sends impulses for muscle movement(reflexes) Digestive—regulates the speed at which food moves through the tract Circulatory– regulates heart rate and blood pressure

The Excretory System Purpose: to rid the body of wastes, including excess water and salts Major Organs and Their Functions Kidneys – the main organs of the excretory system -- filters out urea, excess water and other waste products, which eventually travel out of the kidney as urine -- eventuall bladder and stored until released Rectum – solid (food) waste travels out of the body through the rectum

Skin – sweat glands remove excess water and salts from the body Lungs – expel the waste gas carbon dioxide

The Excretory System

Interactions – Working with Other Systems -- Circulatory: filters waste out of blood --Respiratory: lungs release cellular waste in the form of gas(CO2)

The Respiratory System Purpose: to provide the body with a fresh supply of oxygen for cellular respiration and remove the waste product carbon dioxide Major Organs and Their Functions Nose – internal entry and exit point for air Pharynx – serves as a passage way for both air and food at the back of the throat Larynx – your “voicebox”, as air passes over your vocal chords, you speak Trachea – the “windpipe”, or what connects your pharynx to your lungs

Bronchi – the two large passageways that lead from the trachea to your lungs (one for each lung) alveoli-- tiny air sacs -- capillaries surrounding each alveoli is where the exchange of gases with the blood occurs The diaphragm is the muscle that causes you to breath

Image of the Respiratory System

Interactions – Working with Other Systems Circulatory: takes in O ₂ for delivery to cells and removes CO ₂ brought from cells Excretory: removes excretory waste CO 2 Nervous: signals controls breathing rate Muscular: diaphragm controls breathing by pushing on lungs

The Skeletal System Purpose: to provide structure and support to the human, protect organs and make new blood cells Major Bones of the Human Body 206 bones -- femur (thigh bone)-- humerus (upper arm) -- radius and ulna (lower arm)-- cranium (skull) -- clavicle (shoulder blade) -- fibula and tibia (calf) -- vertebrae (back) -- scalpula (shoulder)-- pelvic bone phalanges (fingers/toes) Ligaments—connect bone to bone at JOINTS(where bones come together)

Interactions – Working with Other Systems Muscular: allow movement Circulatory: produce blood cells Immune: produce white blood cells Circulatory and Respiratory: protects its organs

The Endocrine System Purpose: to control growth, development, metabolism and reproduction through the production and secretion of hormones Major Organs -- hypothalamus -- pituitary gland -- thyroid -- parathyroid -- adrenal glands -- pancreas -- testes -- ovaries

Interactions – Working with Other Systems Circulatory: transports hormones to target organs Nervous: maintain homeostasis, hormone release Reproductive: controlled by hormones Skeletal: controls growth of bones

The Muscular System Purpose: works with the skeletal and nervous system to produce movement, also helps to circulate blood through the human body -- muscle contractions can be voluntary or involuntary Major Muscles in the Human Body -- biceps -- triceps-- deltoids -- glutes-- hamstrings Heart—only muscle that does not rest Tendons—connect muscles to bones

Interactions – Working with Other Systems Skeletal: allow movement Digestive: allow organs to contract to push food through Respiratory: diaphragm controls breathing Circulatory: controls pumping of blood (heart) Nervous: controls all muscle contractions

The Immune System Purpose: to remove infectious diseases and other pathogens from the human body Major Organs and Their Functions Skin – the skin is the body’s first line of defense White Blood Cells – recognize disease agents (antigens) and create antibodies to tag and remove these antigens -- Lymph Nodes – help restore fluid lost by the blood and return it to the circulatory system --Spleen—rids the body of worn out cells and produces white blood cells

Interactions – Working with Other Systems With Circulatory: transports WBC’s to fight invaders With Skeletal: WBC’s made in bone marrow

Major Organs: Females (ovaries) – house offspring Males (testes) Purpose: produce sex cells to create offspring ; controls female and male characteristics

Interactions – Working with Other Systems Endocrine: controls production of sex cells Muscular: muscles contract during birth