Cells!

Cell theory Everything Is made from cells! Many different types of cells!

White blood cells

Onion epidermal cells

Breast Cancer Cells

Overview of cells Plasma membrane – defines boundary of cell and regulates chemical traffic between cells and walls Nucleus - houses cell DNA – genetic material Cytoplasm – region between nucleus and plasma membrane Contains fluid and organelles Made of water Organelle – parts of cell that have specific function Plasma membrane - think of a door and wall.. The door regulates where it goes Each cell

Notice major differences Chlorplasts Plants have cell walls – made of chitin and cellulose

Two types of cells Prokaryotic cells - do not have nucleus and organelles Bacteria Archaea – “extremeophiles” Eukaryotic cells – have a true nucleus

Membrane Structure Organization Isolate teams of enzymes Regulate transport Mainly of proteins and phosphlipids Polar and nonpolar Membranes keep functions of eukaryotic cell organized Isolate enzymes Regulate transport of substances across the boundary Phspholi[ds have phostphate group (PO4 3-) attracted to water – negatively charge Hydrophobic head Hydrophobic tail (nonpolar)

Phospholipid bilayer Phosphate ends face water (hydrophilic and inside cell – cytoplasm) Hydrophobic ends inside, away from water! Nonpolar molecules such as Oxygen and Carbon dioxide pass through easily whereas polar molecules cannot! Dynamic structure – always moving

Functions of Membrane Proteins Enzyme Activity Cell to cell recognition Communicate (search for pathogens) Cell signaling Informing other cells Transport of materials