History of Cell History of Cell DiscoveryDiscovery

Chapter 4

Microscope view of cellsMicroscope view of cells

►Robert HookeRobert Hooke – first to see cells! – first to see cells! designed microscope that he was designed microscope that he was able to view cork cells with (1665).able to view cork cells with (1665).►Named “Cells” because Named “Cells” because they look like monk quartersthey look like monk quarters

Cells with stone beds

Microscope view of cellsMicroscope view of cells

Anton Van LeeuwenhoekAnton Van Leeuwenhoek – first to see – first to see living cells.living cells.

► improved design, and was improved design, and was

able to view red blood cells able to view red blood cells

and bacteria.and bacteria. Called them "animalicules"Called them "animalicules"

Scientists of Cell TheoryScientists of Cell Theory

►Theodore SchwannTheodore Schwann – zoologist who – zoologist who observed that the tissues of animals observed that the tissues of animals had cells (1839)had cells (1839)

Scientists of Cell TheoryScientists of Cell Theory

►Mattias SchleidenMattias Schleiden – botanist who – botanist who observed that the tissues of plants had observed that the tissues of plants had cells (1845)cells (1845)

Scientists of Cell TheoryScientists of Cell Theory

►Rudolf VirchowRudolf Virchow – reported that every – reported that every living thing is made up of cells, and living thing is made up of cells, and that these cells must come from other that these cells must come from other cells.cells.

Cell TheoryCell Theory

1.1. All living things are made of one or All living things are made of one or more cells.more cells.

2.2. Cells are the basic unit of structure Cells are the basic unit of structure and function in organisms. and function in organisms.

(the smallest unit that can perform life (the smallest unit that can perform life functions)functions)

3.3. All cells come from pre - existing All cells come from pre - existing cells.cells.

TermsTerms

► CellCell – the smallest unit that – the smallest unit that can carry on the processes of can carry on the processes of life.life.

► UnicellularUnicellular – consists of only – consists of only one cellone cell

►MulticellularMulticellular – consists of more – consists of more than one cellthan one cell

Basic cell Structures

►Cell Membrane – outer boundary

►Nucleus – control center

►Cytoplasm – stuff between membrane & nucleus

Two Basic Cell TypesTwo Basic Cell Types►Prokaryotic Prokaryotic – lacks internal – lacks internal

structures surrounded by structures surrounded by membranes. membranes.

Has a cell membrane & a cell wallHas a cell membrane & a cell wall Has Has NONO nucleus. nucleus. ►Means “before the nucleus”Means “before the nucleus”

Usually Unicellular organismsUsually Unicellular organisms Ex: Bacteria Ex: Bacteria

Two Basic Cell TypesTwo Basic Cell Types

►Eukaryotic Eukaryotic – contains internal – contains internal membrane bound structures. membrane bound structures.

Has a nucleusHas a nucleus Has a cell membraneHas a cell membrane Usually multicellular organismsUsually multicellular organisms Ex: Plants, animals, and protists Ex: Plants, animals, and protists