Copyright Pearson Prentice Hall 7-1 Life Is Cellular Photo Credit: © Quest/Science Photo Library/Photo Researchers, Inc. Copyright Pearson Prentice Hall

The Discovery of the Cell Early Microscopes In 1665, Robert Hooke used a microscope to look at a thin slice of cork. Cork looked like thousands of tiny, empty chambers he called “cells”. Cells are the basic units of life. Copyright Pearson Prentice Hall

The Discovery of the Cell Hooke’s Drawing of Cork Cells hoto Credit: © Peter Arnold, Inc. Copyright Pearson Prentice Hall

The Discovery of the Cell At the same time, Anton van Leeuwenhoek used a single-lens microscope to observe pond water. The microscope revealed a world of tiny living “animacules”. Copyright Pearson Prentice Hall

The Discovery of the Cell The Cell Theory In 1838, Matthias Schleiden concluded that all plants were made of cells. In 1839, Theodor Schwann stated that all animals were made of cells. In 1855, Rudolph Virchow concluded that new cells were created only from existing cells. Copyright Pearson Prentice Hall

The Discovery of the Cell The cell theory states: All living things are composed of cells. Cells are the basic units of structure and function in living things. New cells are produced from existing cells. Copyright Pearson Prentice Hall

Prokaryotes and Eukaryotes Prokaryotic cells have genetic material, but not in a nucleus. No organelles. Smaller and simpler. Ex) Bacteria are prokaryotes. Copyright Pearson Prentice Hall

Prokaryotes and Eukaryotes Eukaryotic cells contain a nucleus with the genetic material. Have organelles. Larger & more complex. Copyright Pearson Prentice Hall

Classification of Life 5 Kingdom System Monera – prokaryotes Plants – eukaryote, cell wall, chlorophyll Fungi – eukaryote, cell wall, no chlorophyll Animal – eukaryote, no wall, multicellular Protista – eukaryote, no wall, unicellular Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 7-1 The cell theory states that new cells are produced from nonliving material. existing cells. cytoplasm. animals. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 7-1 The person who first used the term cell was Matthias Schleiden. Lynn Margulis. Anton van Leeuwenhoek. Robert Hooke. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 7-1 Electron microscopes are capable of revealing more details than light microscopes because electron microscopes can be used with live organisms. light microscopes cannot be used to examine thin tissues. the wavelengths of electrons are longer than those of light. the wavelengths of electrons are shorter than those of light. Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 7-1 Which organism listed is a prokaryote? protist bacterium fungus plant Copyright Pearson Prentice Hall

Copyright Pearson Prentice Hall 7-1 One way prokaryotes differ from eukaryotes is that they contain DNA, which carries biological information. have a surrounding barrier called a cell membrane. do not have a membrane separating DNA from the rest of the cell. are usually larger and more complex. Copyright Pearson Prentice Hall