Unit 4: Cells and the internal environment Journal 4-1 Notes

Levels of Organization in Biology Small systems to Big systems

This Section deals with Internal Cellular Environments And Homeostasis

Unit 4: Internal Environment What the is the “Internal Environment”? Your… Cells Tissues organs Cells - functional unit of life Cells require certain internal conditions to function What do we know about Enzyme activity to support this statement?

Maintaining a Balance Homeostasis - maintaining a stable, constant internal environment Organisms maintain constant internal levels of…. Water Blood glucose Oxygen in the blood Electrolytes (sodium, potassium, etc…) What will we study? Cells and Molecular Movement Body systems - circulatory, urinary

Digestive System (Review) What is the purpose of ingesting food (eating)? Small Intestine - location of absorption of nutrients. Where do the nutrients go? How does this happen? Nutrients must move from the external environment to the internal environment.

Absorption in the Small Intestine Diffusion - movement of molecules from an area of high concentration to an area of low concentration Nutrients move into blood stream