Three Sections of the Cell Cell = Basic unit of life All cells take in food, rid waste, reproduce 3 main sections 1) Nucleus 2) Cytoplasm 3) Plasma Membrane

Cytoplasm Jelly-like material inside of the cell Continuously in motion Most organelles float within Job: Allow chemical reactions to take place

Plasma Membrane Aka: Cell Membrane Job: Allow materials to enter/exit Composition: Lipids & proteins Semi-Permeable: only some materials may enter and exit Through pores and protein channels Many materials enter/exit as a result of diffusion Plasma Membrane

Nucleus Job: Controls cell activity Where DNA is made & stored DNA holds info to make proteins Surrounded by Nuclear Envelope Inside: 1) Chromatin: long strands of DNA 2) Nucleolus: makes ribosomes Nucleus

Endoplasmic Reticulum Aka: ER Rough ER: Tunnel system that transports ribosomes and proteins Smooth ER: makes fats & breaks down toxins (no ribosomes)

Ribosomes Created by nucleolus Transported by the rough ER Some attached to ER… some free-floating Transported by the rough ER Job: make proteins

Golgi Apparatus Job: Package and transport proteins out of the cell Process Review 1) Genes hold instructions for making proteins 2) Nucleolus makes a ribosome 3) Ribosome makes protein & travels through rough ER 4) Golgi Body packages the protein into a vesicle and exports them

Golgi Body in action

Mitochondria Powerhouse: Releases energy to the cell Job: Create ATP (the energy used by cells) in a process called cellular respiration Why more abundant in muscle cells? Endosymbiosis theory: Once free living

Lysosome Contain digestive enzymes Functions: 1) Break down food 2) Kill bacteria 3) Autolysis: Destroy dying cell

Cilia & Flagella Made of protein Used in locomotion Cilia = short hair like extensions (numerous) Flagella = long whip-like extension (very few)

That one magical night!

Vacuole Job: Stores food, water, waste, color pigments Job: add support Swells & shrinks with H2O supply Plant cells: Large central vacuole (as pictured) Animal cells: Scattered smaller vacuoles

Cell Wall Outermost layer of plant, fungi, & bacteria cells Job: Adds support to growing plants Made of tough cellulose Hard to digest Witnessed by Robert Hooke in 1665

Chloroplast Job: Perform photosynthesis (plants) CO2 + H20 + sunlight  Sugar + O2 Chlorophyll absorbs sunlight & converts it into glucose (sugar) Endosymbiosis: Once free-living

Quick Review Different cells have many similar parts Tiny parts are called “organelles” Each organelle has a separate function