Cell Structures & Processes AP Biology Chapter 6

Human Eye Only sees objects >100 µm

Light Microscopes Advantages Disadvantages Inexpensive View living organisms Disadvantages Magnification is limited

Electron Microscope Advantages Disadvantages Greater magnification Expensive Destroy the organisms

Calculating Total Magnification Ocular Lens mag. X Objective mag. = Total mag. (Low Power) 10 X 4 = 40X magnification

Evolution of Life on Earth All living organisms have order Many life structures are microscopic

Cell Theory All living things are composed of cells The cell is the basic unit of life New cells are produced from existing cells.

Common Cell Characteristics Cell membrane Cytoplasm Genetic Material Ribosomes

Cell Types Prokaryotic Cells Eukaryotic Cells Small Nucleoid region Larger but still small Nucleus Many organelles

Organelle Groups Nuclear Region Cytoplasmic Region Surface Region

Nuclear Region Nucleus Nuclear Envelope Control center of the cell Contains nearly all cell DNA Nuclear Envelope Surrounds the nucleus Contains nuclear pores Move into & out of the nucleus

Nuclear Region Chromatin Nucleolus DNA bound to a protein Condenses to form chromosomes Nucleolus Small, dense region Assembles ribosomes

Cytoplasmic Region Cytoplasm The portion of the cell outside the nucleus Gel-like substance: allows movement Contains many organelles

Cytoplasmic Region 6. Ribosome Small particles of RNA and protein Assembles proteins based on instructions provided by the nucleus

Cytoplasmic Region Rough ER Smooth ER Ribosomes are found on its surface Involved in the synthesis of proteins Smooth ER Contains collections of enzymes Synthesizes membrane lipids Detoxifies drugs

Cytoplasmic Region Golgi Apparatus (Golgi Body) Vesicles It modifies, sorts, and packages proteins for storage or secretion Ships proteins to their final destination Vesicles structures that carry material

Cytoplasmic Region Lysosomes Small organelles filled with enzymes Digestion, or breakdown, of lipids, carbohydrates, and proteins so the rest of the cell can use them Removes dead organelles

Cytoplasmic Region Vacuoles Saclike structures that stores materials Plant cells: large organelle filled with liquid Help maintain homeostasis Also found in animal cells

Cytoplasmic Region Mitochondria Power house of the cell Provides the cell with energy Converts stored energy in food into compounds that the cells can use Contains its own DNA

Cytoplasmic Region Chloroplasts Only found in plant cells Capture energy from sunlight and convert it into chemical energy This process is called photosynthesis Contains chlorophyll Contains its own DNA

Cytoplasmic Region Centrioles Located near the nucleus Help to organize cell division Only in Animal Cells

Surface Region Cytoskeleton A network of protein filaments Help the cell maintain its shape Also aids in movement Flagellum Cilia

Surface Region Cell membrane Cell wall Cell membrane regulates what enters and leaves the cell Provides protection and support Cell wall Main function is to provide support and protection Only in plant cells