Cell Biology Van Leeuwenhoek and his microscope Robert Hooke, and his drawing of cells Schleiden and Schwann

Cell Biology Overview A. Types of Cells 1. Prokaryotic Cells (eubacteria and archaea) - no nucleus - no organelles - binary fission - small (0.2 – 2.0 um)

Cell Biology Overview A. Types of Cells 1. Prokaryotic Cells 2. Eukaryotic Cells (protists, plants, fungi, animals) - nucleus - organelles - mitosis - larger (10-100 um)

Cell Biology Overview A. Types of Cells 1. Prokaryotic Cells 2. Eukaryotic Cells B. How Cells Live - take stuff in

Cell Biology Overview A. Types of Cells 1. Prokaryotic Cells 2. Eukaryotic Cells B. How Cells Live - take stuff in - break it down and harvest energy (enzymes needed) mitochondria ADP +P ATP

Cell Biology Overview A. Types of Cells 1. Prokaryotic Cells 2. Eukaryotic Cells B. How Cells Live - take stuff in - break it down and harvest energy (enzymes needed) and - transform radiant energy to chemical energy ADP +P ATP chloroplast mitochondria ADP +P ATP

Cell Biology Overview A. Types of Cells 1. Prokaryotic Cells 2. Eukaryotic Cells B. How Cells Live - take stuff in - break it down and harvest energy (enzymes needed) - use energy to make stuff (like enzymes and other proteins, and lipids, polysaccharides, and nucleic acids) - DNA determines sequence of amino acids in enzymes and other proteins ADP +P ATP ribosome

ADP +P ATP ribosome

Cell Biology Overview II. Membranes – How Things Get in and Out of Cells A. Membrane Structure 1. phospholipids

Cell Biology Overview II. Membranes – How Things Get in and Out of Cells A. Membrane Structure 2. proteins and carbohydrates

Cell Biology Overview II. Membranes – How Things Get in and Out of Cells A. Membrane Structure B. Membrane Function 1. semi-permeable barrier Aqueous Solution (outside cell) dissolved ions dissolved polar molecules suspended non-polar (lipid soluble) Aqueous Solution (inside cell) dissolved ions dissolved polar molecules suspended non-polar (lipid soluble)

Cell Biology Overview II. Membranes – How Things Get in and Out of Cells A. Membrane Structure B. Membrane Function 1. semi-permeable barrier 2. transport Net diffusion Net diffusion equilibrium

Cell Biology Overview II. Membranes – How Things Get in and Out of Cells A. Membrane Structure B. Membrane Function 1. semi-permeable barrier 2. transport - diffusion Net diffusion Equilibrium Net diffusion Net diffusion equilibrium

Cell Biology Overview II. Membranes – How Things Get in and Out of Cells A. Membrane Structure B. Membrane Function 1. semi-permeable barrier 2. transport - osmosis

Cell Biology Overview II. Membranes – How Things Get in and Out of Cells A. Membrane Structure B. Membrane Function 1. semi-permeable barrier 2. transport – facilitated diffusion

Cell Biology Overview II. Membranes – How Things Get in and Out of Cells A. Membrane Structure B. Membrane Function 1. semi-permeable barrier 2. transport – active transport

Cytoplasmic Na+ bonds to the sodium-potassium pump Na+ binding stimulates phosphorylation by ATP. Phosphorylation causes the protein to change its conformation, expelling Na+ to the outside. Extracellular K+ binds to the protein, triggering release of the phosphate group. Loss of the phosphate restores the protein’s original conformation. K+ is released and Na+ sites are receptive again; the cycle repeats.

Cell Biology Overview II. Membranes – How Things Get in and Out of Cells A. Membrane Structure B. Membrane Function 1. semi-permeable barrier 2. transport 3. metabolism (enzymes nested in membrane) 4. signal transduction

Cell Biology Overview II. Membranes – How Things Get in and Out of Cells A. Membrane Structure B. Membrane Function 1. semi-permeable barrier 2. transport 3. metabolism (enzymes nested in membrane) 4. signal transduction 5. cell-cell binding 6. cell recognition 7. cytoskeleton attachment