Cytoplasm- the fluid portion of the cell outside the nucleusOrganelle- 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 cellCytoskeleton- 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 synthesisEndoplasmic 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 useLipid 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

1st to see single-celled organisms in pond water

Microscope VocabularyMagnification: increase of an object’s apparent size Resolution: power to show details clearlyBoth are needed to see a clear image

Types of Microscopes1. Compound Light Microscope

1st type of microscope, most widely usedlight passes through 2 lensesCan magnify up to 2000x

Ocular lens

Objective lenses

Compound Light Microscope Parts

A

B

C

D

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A. Eyepiece: Holds ocular lens; lens that you look through; magnified image of objective lens

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

B

C

D

E

F

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H. Diaphragm: Controls the amount of light that passes through a specimen

I. Stage: platform that holds the slideJ. Microscope slide: holds the specimenK. Objective lenses: magnifies the specimen

Shortest lens has least magnificationLongest lens has greatest magnification

Types of Microscopes2. Electron Microscope

Used to observe VERY small objects: viruses, DNA, parts of cellsUses beams of electrons rather than lightMuch 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

http://www.mos.org/sln/sem/flea.gif