1. Human Systems: Body Organization

2. 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

3. Cells, tissues, organs
Cells must do many things to maintain homeostasis
Cells – different types of function and specialization

4. Cells, tissues, organs
Cells form tissues (group of same type of cells performing same function)

5. Cells, tissues, organs Tissues form organs
Different functions in same place - coordination

6. 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

7. Cells, tissues, organs

8. 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

9. 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

10. 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

11. 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