Transcript Document
Cytoplasm- the fluid portion of the cell outside the nucleus Organelle- a specialized structure that performs important cellular functions within a eukaryotic cell. Vacuole- the cell organelle that stores materials such as water, salts, proteins, and carbohydrates. Lysosome- the cell organelle that breaks down lipids, carbohydrates, and proteins into small molecules that can be used by the rest of the cell Cytoskeleton- the network of protein filaments in a eukaryotic cell that gives the cell its shape and internal organization and is involved in movement. Ribosome- a cell organelle consisting of RNA and protein found throughout the cytoplasm in a cell; the site of protein synthesis Endoplasmic reticulum- the internal membrane system found in eukaryotic cells; the place where lipid components of the cell membrane are assembled. Golgi apparatus- an organelle in cells that modifies, sorts, and packages proteins and other materials from the endoplasmic reticulum for storage in the cell or release outside the cell. Chloroplast- an organelle found in cells of plants and some other organisms that captures the energy from sunlight and converts it into chemical energy Mitochondrion- a cell organelle that converts the chemical energy stored in food into compounds that are more convenient for the cell to use Lipid bilayer- a flexible double-layered sheet that makes up the cell membrane and forms a barrier between the cell and its surroundings How do we know cells exist? Microscopes History of the Microscope 1590 –first compound microscope History of the Microscope 1655 – Robert Hooke used a compound microscope to observe pores in cork He called them “cells” History of the Microscope Antoine van Leeuwenhoek st 1 to see single-celled organisms in pond water Microscope Vocabulary Magnification: increase of an object’s apparent size Resolution: power to show details clearly Both are needed to see a clear image Types of Microscopes 1. Compound Light Microscope 1st type of microscope, most widely used light passes through 2 lenses Can magnify up to 2000x Ocular lens Objective lenses Compound Light Microscope Parts A M L B C K J D I E H G A. Eyepiece: Holds ocular lens; lens that you look through; magnified image of objective lens F B. Arm: supports tube & connects it to the base C. Stage Clip: holds microscope slide in place D. Coarse adjustment: raises / lowers stage to bring image into focus E. Fine adjustment: brings image into sharp focus F. Base: Supports microscope G. Illuminator: Light source Compound Light Microscope Parts A M L B C K J D I E H G F H. Diaphragm: Controls the amount of light that passes through a specimen I. Stage: platform that holds the slide J. Microscope slide: holds the specimen K. Objective lenses: magnifies the specimen Shortest lens has least magnification Longest lens has greatest magnification Types of Microscopes 2. Electron Microscope Used to observe VERY small objects: viruses, DNA, parts of cells Uses beams of electrons rather than light Much more powerful Types of Microscopes Transmission Electron Microscope (TEM) Can magnify up to 250,000x Types of Microscopes Scanning Electron Microscope (SEM) Can magnify up to 100,000x