Human Systems: Body Organization
Human Body 100 trillion cells More than 100 kinds of cells Organization – cells, tissues, organs, organ systems Coordination Control mechanisms Maintaining internal environment (homeostasis) Homeostasis and cell function
Cells, tissues, organs Cells must do many things to maintain homeostasis Cells – different types of function and specialization
Cells, tissues, organs Cells form tissues (group of same type of cells performing same function)
Cells, tissues, organs Tissues form organs Different functions in same place - coordination
Organ systems Organs form organ systems Stomach helps in food digestion but cannot digest food alone Additional help needed by other organs of the digestive system Mouth (saliva secretion), pancreas, gall bladder, intestine Nervous system – brain, spinal cord, nerves Organs perform specialized function in a coordinated manner
Cells, tissues, organs
Organ systems Organ systems work together to perform body processes E.g. cardiovascular system (circulatory system) works with respiratory system to perform exchange of gases Nervous system works with skeletal and muscular systems for producing movements Urinary, digestive and respiratory systems work together for excretion of wastes Digestive and circulatory systems work together to obtain and distribute nutrients
Organ systems Interdependence of organ systems Some organs perform jobs essential for more than one system E.g. pancreas – digestive and endocrine systems Stomach – digestive system and communication Liver – carbohydrate, protein, lipid metabolism, drug metabolism, detoxification, waste (urea) management, store materials
Organ systems When systems fail Systems must function properly and work together in order to maintain homeostasis Failure of even a part of a system can result in a disorder affecting the whole organism may result in death
Organ systems E.g. angina – a heart disorder Blood supply to heart is restricted Heart cannot pump blood efficiently Depletion of nutrients and oxygen in body cells E.g. diabetes – a pancreatic disorder Problem in insulin production or action Increase in blood glucose level Can damage eyes, kidneys, brain, nerves, movement of substances, limbs, digestive system