The Cell Theory All organisms are composed of one or more cells. 7.1 Cell Discovery and Theory Cellular Structure and Function The cell is the basic unit of structure and organization of organisms. Chapter 7 All cells come from preexisting cells. Cell division
Important People and Events Robert Hooke – First coins the term “cells” –Saw first cells in cork Anton van Leeuwenhoek – discovers single- celled organisms Louis Pasteur and Robert Koch – pioneered study of bacteria Development of scanning tunneling microscope in 1981 allows scientists to see atoms
Cellular Structure and Function Light Microscopes Utilizes a series of glass lenses and visible light to magnify an image Magnifies images up to 1,000 times the actual size 7.1 Cell Discovery and Theory Chapter 7
Electron Microscopes Cellular Structure and Function Utilizes magnets to aim a beam of electrons at a cell to produce an image Magnifies images up to 500,000 times the actual size 9560x 7.1 Cell Discovery and Theory Chapter 7
Prokaryotic Cell Essentially a simple structure Cellular Structure and Function Contains a plasma membrane Does not contain membrane-bound organelles 11,000x 7.1 Cell Discovery and Theory Chapter 7 Prokaryotic Cells are usually bacteria and other unicellular organisms.
Eukaryotic Cell More complex structure Cellular Structure and Function Contains a plasma membrane Contains membrane- bound organelles 400x 7.1 Cell Discovery and Theory Chapter 7 Eukaryotic Cells make up organisms such as animals, plants, algae and yeast.
Plasma Membrane Thin, flexible boundary between the cell and its environment 7.2 The Plasma Membrane Cellular Structure and Function Allows nutrients into the cell Allows waste to leave the cell Chapter 7
Selective Permeability Cellular Structure and Function The plasma membrane controls the movement of substances into and out of the cell. Plasma Membrane Controls the amount of a substance entering the cell Controls the amount of a substance leaving the cell 7.2 The Plasma Membrane Chapter 7
The plasma membrane is composed of the phospholipid bilayer. Cellular Structure and Function A phospholipid molecule is composed of a glycerol backbone, two fatty acid chains, and a phosphate group. 7.2 The Plasma Membrane Chapter 7
Fluid Mosaic Model Cellular Structure and Function The phospholipid bilayer allows other molecules to “float” in the membrane. Other Components Proteins Cholesterol Carbohydrates 7.2 The Plasma Membrane Chapter 7
Proteins Cellular Structure and Function Transmit signals inside the cell Act as a support structure Provide pathways for substances to enter and leave 7.2 The Plasma Membrane Chapter 7
Cholesterol Cellular Structure and Function Prevents fatty acid tails from sticking together 7.2 The Plasma Membrane Chapter 7
Carbohydrates Cellular Structure and Function Identify chemical signals 7.2 The Plasma Membrane Chapter 7
Tue., November 29 th FOCUS QUESTION: HOMEWORK: CLASSWORK / OBJECTIVES: Journal Go over study guide Notes Ch. 7.3 Cell Organelle Chart Name and describe two types of microscopy. Work on Cell Organelle Chart TURN IN: Study Guide