Cell Structure and Function

• Prokaryotic Kingdoms: Eubacteria and Archaebacteria
• Eukaryotic Kingdoms: Animals, Fungi, Protists, and Plants
• In 1665 Robert Hooke coined the term "cells"
• Robert Hooke observed cells in cork
• In 1673 Anton van Leeuwenhoek created a powerful microscope
• 1800s: Robert Brown noticed that pollen grains in water jiggled around called "Brownian motion" (century)
• Who discovered the nucleus?

  Robert Brown
• 1800s: Matthias Schleiden (a botanist) concluded that all plants are made of cells (what century)
• 1800s: Theodor Schwann (a zoologist) concluded that all animals are made of cells (century)
• All cells have

  • Plasma (cell) membrane
  • Nucleus/nuclear area
  • Cytoplasm (an area)
  • Ribosomes (structure needed to make proteins)
  • Genetic Material (DNA)
• Prokaryotic Domain: Bacteria
• Eukaryotic Domains: Archaea and Eukarya
• Omnis cellula e cellula


  All cells come from pre-existing cells
• 1800s: Rudolph Virchow

  A physician who did research on cancer cells and concluded, “Omnis cellula e cellula"
• Cell Theory

  1. All living things are composed of one or more cells
  2. Cells are the basic units of structure and function in an organism
  3. Cells come only from existing cells
• True nucleus

  • Has nuclear membrane
  • Linear DNA
• Prokaryotes lack a true nucleus
• Eukaryotes have a true nucleus
• Prokaryotes have small ribosomes
• Eukaryotes have large ribosomes
• The DNA of a prokaryote is organized into circular shaped chromosomes
• The DNA of a eukaryote is organized into linear shaped chromosomes
• The flagella of a prokaryote are not made of microtubules and do not have a 9+2 structure
• The flagella of a eukaryote are made of microtubules and have a 9+2 structure
• The cell walls of a prokaryote are made of peptidoglycan
• The cell walls of a prokaryote are made of peptidoglycan
• Prokaryotes are simple cells that do not have internal membranes and lack a true nucleus
• Eukaryotes are more complex cells that have internal, membrane bound structures and a true nucleus
• An example of a prokaryote is bacteria
• Examples of eukaryotes are plants and animals
• True nucleus is found in eukaryotes
• True nucleus has a membrane
• Nuclear region is found in prokaryotes
• Nuclear region lacks a membrane
• Nucleolus is inside the nucleus
• Nucleolus lacks a membrane
• Spread out DNA: Chromatin
• Condensed DNA: Chromosomes
• Eukaryotes and prokaryotes have a cell membrane
• Function of the cell membrane


  Controls what enters or leaves the cell