Introduction to Cells

Cell Shape The diversity in a cells shape reflects the different functions of cells Example: Long extensions in nerve cells

Cell Size The cell’s size is limited by the relationship of the cell’s outer surface area to its volume Most cells typically 10-50 micrometers

Basic Parts of a Cell Plasma Membrane Cytoplasm Control Center

Plasma Membrane Cell’s outer boundary Covers the Cells Surface Acts as a barrier between the inside and the outside of the cell

Cytoplasm Region within the plasma membrane Includes the fluid, the cytoskeleton, and all of the organelles except the nucleus

Nucleus Membrane-bound organelle that contains a cell’s DNA Control Center for the Cell

Two Basic Types of Cells Prokaryotes Lack a nucleus and membrane-bound organelles Have a nucleoid instead of a nucleus Examples are all bacteria and cyanobacteria

Two Basic Types of Cells Eukaryote Cells Contains a nucleus Has membrane-bound organelles Examples are plant cells, protists, fungi, and animal cells

Organelles Subcellular structures that are well-defined, intracellular bodies that perform specific functions of the cell Examples: Nucleus, Golgi Body, Mitochondria, etc

Cellular Organization Multi-cellular Eukaryotes Organize into tissues, organs, organ systems, and finally organisms