AP6

Sherwood pp. 2-14

FOCUS ON

• Organization of the human body (chemicals, cells, organs etc)

• Homeostasis• Negative feedback• Functions of the organ systems• (Ignore the last 4 slides)

Organization of human body

• Chemicals• Cell• Tissue: similar structure and function– E.g. connective, muscle, nerve, epithelial

• Organ: group of tissue organized for specific functions

• Organ systems• Organism

Organ systems

Homeostasis

• E.g. when body gets cold, shivering generates heat.

• Homeostasis: maintaining a relatively stable environment within the body

Some things that are balanced

• 1. concentration of O2 and CO2: CO2 production must be balanced by CO2 removal

• 2. pH• 3. Concentration of water, salt, other

electrolytes• 4. Temperature• 5. Nutrients

Negative feedback

• E.g. rise in body temperature -> sweating -> cooling of body temp

• Negative feedback: imp’t in maintaining homeostasis.

• NF: A bodily response that opposes the change

Positive feedback

• E.g. oxytocin during childbirth

• (don’t worry about this one too much)