Cells and Tissues

1. Cells and Tissues

2. The Smallest Unit of Life

3. Animal Cell

4. Size of Bacteria Limited by: • Rate of Diffusion • Molecules must move to ‘find’ where they are suppose to be. In a crowded environment, this might take a while unless the space is small. • Surface Area • Smaller cells have relatively large ‘surface to volume’ ration—more surface area for the volume inside. This helps with entry of nutrients and removal of waste, as both have to cross the ‘surface’. More area to cross (per volume)=better.

6. polar

7. “Self-Sealing”

13. Passive Transport Molecules move from where they are most abundant (high concentration) to where they are sparse (low concentration).

15. Active Transport

16. Endocytosis (stuff from out  in Exocytosis (stuff from in  out Phagocytosis (BIG stuff from out  in)

17. Movement Across Cell Membranes • Passive Transport (No Energy; From Hi Low) • Simple Diffusion • Facilitated Diffusion (Requires Channel or Carrier) • Active Transport (Energy; Low Hi) • Bulk Transport • Pinocytosis • Endocytosis • Phagocytosis • Exocytosis

18. Epithelial Tissues Functions = Barrier & Secretion

19. Connective Tissues Functions = Structure & Support (& ‘nutrition’)

20. Muscle Tissues Functions = Contraction & Movement

21. Nervous Tissues Function = Communication

22. Tissues: • Cells generally stick to each other (cell junctions) • Cells generally stick to a ‘ground’ (extracellular matrix junctions) • Cells generally communicate with each other

23. Cell Junctions

24. Tissues Organs Organ Systems

25. Organ Systems