Human Body system fuctions

• Your body is made up of millions of cells that work together and are very organized with specific functions
• Cells carry your whole DNA code, but use specific parts of your DNA code depending on the cell's function
• Cells make up body tissues, tissues make up organs, and organs are part of an organ system
• Organ systems do not work in isolation, they work together as part of a big team
• 11 major organ systems

  • Circulatory
  • Digestive
  • Endocrine
  • Excretory
  • Integumentary
  • Lymphatic/Immune
  • Muscular
  • Nervous
  • Reproductive
  • Respiratory
  • Skeletal
• Circulatory system


  Transports blood, gases like oxygen, and nutrients
• Circulatory system


  • Heart is a pumping machine that transports blood
  • Arteries carry blood away from the heart
  • Veins carry blood back to the heart
  • Capillaries are tiny blood vessels throughout the body
• Blood is always red, even inside the body, though the shade can vary slightly due to the amount of oxygen present
• Digestive system


  Breaks down and absorbs food to get nutrients
• Digestive process


  1. Starts in the mouth with enzymes in saliva

  2. Stomach contains acid to further the process

  3. Small intestine does most of the absorption of nutrients

  4. Large intestine reabsorbs water
• Endocrine system


  Includes glands that secrete hormones
• Excretory system


  Removes wastes from the body, like urine
• Excretory system


  • Kidneys assist in removing wastes from the blood
  • Includes other ways of removing waste, like sweating
• Integumentary system


  Your skin, the largest organ
• Lymphatic/Immune system


  Collects, filters, and returns lymph fluid to the blood, and helps with immune function
• Lymphatic/Immune system


  • Structures like lymph nodes, thymus, spleen, tonsils, and bone marrow play significant roles
• Muscular system


  Includes skeletal, smooth, and cardiac muscle
• Nervous system


  Coordinates voluntary and involuntary actions, using neurons
• Reproductive system


  Includes reproductive organs and allows for reproduction
• Respiratory system


  Involves the lungs, intake of oxygen and exhaling of carbon dioxide
• Skeletal system


  • Adults have 206 bones that support, protect organs, and produce blood cells
• Understanding how the human body works is necessary to figure out what to do when things go wrong
• The human body is a magnificent masterpiece with all the organ systems working together
• Lymph nodes


  Small, bean-shaped organs that filter lymph fluid and help fight infection. They contain immune cells called lymphocytes that destroy harmful substances and infectious agents.
• Thymus


  A gland located in the chest that helps produce and mature T-cells, a type of white blood cell that plays a central role in the immune response.
• Spleen


  An organ that filters the blood and removes waste and foreign substances. It also stores red and white blood cells and releases them into the bloodstream as needed.
• Tonsils


  Two masses of lymphoid tissue located at the back of the throat that help protect against infection and filter out germs that enter through the mouth and nose.
• Bone marrow


  The spongy tissue found inside bones where blood cells are produced. It produces red blood cells, white blood cells, and platelets, which are essential for the immune system to function properly.
• Human Body Systems


  • Skeletal System
  • Digestive System
  • Respiratory System
  • Circulatory System
  • Excretory System (Urinary System)
• Skeletal System


  • Protection of vital organs
  • Support the body
  • Allow movement
• Digestive System


  Chemically break down food molecules into smaller parts that can be absorbed into the bloodstream
• Respiratory System


  Absorb oxygen gas from the air into the blood, and excrete the waste gas carbon dioxide
• Circulatory System


  Carry food and oxygen to every cell, and collect waste chemicals for excretion
• Excretory System (Urinary System)


  Remove waste materials from the blood stream and excrete them as urine
• Body Control & Co-ordination Systems

  • Nervous System
  • Endocrine System
• Nervous System


  • Receives and interprets information, then decides what to do about it
  • Controls automatic processes like breathing and digestion
• Parts of the Brain


  • Cerebrum
  • Cerebellum
  • Brain Stem
  • Hypothalamus
• Spinal Chord


  Acts as a nerve "highway" connecting the brain to all parts of the body, and controls reflexes
• Reflex


  An automatic body response to a sudden pain, threat, or other stimulus
• Nerve Cells (Neurons)


  Carry messages from one part of the body to another