Bellringer What is the difference between a bacteria and a virus? Are bacteria and viruses harmful, helpful, or neither? If so, how are they harmful, helpful, or neither?

Bacteria and Viruses

Bacteria Prokaryotes-single celled organism lacking nucleus Eukaryote, remember?

Bacteria: 2 Kingdoms 2 Kingdoms: Eubacteria Archeabacteria Lives everywhere Lives in harsh environments Cell wall, peptidoglycan Cell wall, no peptidoglycan

Bacteria: Shapes Shapes: Bacilli-rods Cocci- spheres Spirilla- spiral, corkscrew

Metabolic Diversity Heterotrophs Must take in organic molecules for energy and supply or carbon Chemoheterotroph: Most common. Photoheterotroph: Least common Use photosynthesis for energy but need to take in organic compounds for a carbon source Autotrophs Make their own food. Chemoautotrophs: make organic carbon molecules but do not require light as a source of energy. Photoautotrophs: make organic carbon molecules and require light as a source of energy

Releasing Energy Obligate Aerobes: organisms that require a constant supply of oxygen in order to live. Obligate anaerobes: organisms that must live in the absence of oxygen. Facultative Anaerobes: can survive with or without oxygen.

Bacteria: Cell Walls Cell walls: Bacteria with peptidoglycan absorb violet dye=gram positive Bacteria with less peptidoglycan absorb red dye=gram negative

Bacteria: Motility Movement: Flagella allow reaction towards chemical or physical signals

Bacteria: Reproduction Binary fission-replicates, divides Conjugation-bridge forms, genetic transfer; Diversity! Endospore- enclose DNA, remain dormant until better conditions; forms spores Endospore

Bacteria Functions in Biosphere Decomposer (chemical recycling) Nitrogen Fixers Bioremediation Human uses for food

Viruses Virus- particles of nuclei acid and protein which reproduce by infecting living things DRAW and label

Tobacco Mosaic Virus causes tobacco plants to develop a pattern of spots

Viruses Lytic infection-virus enters cell, makes copies, bursts out of cell

Viruses Lysogenic infection- virus embeds DNA into DNA of host cell and replicated along with host cell’s DNA

Viruses Retroviruses- contain RNA as genetic info; reverse transcription takes place (HIV)

Viruses Prions- contain no DNA or RNA, only protien (Mad Cow Disease)

Diseases Caused by Bacteria and Viruses Bacteria produce disease in one of 2 general ways. Some damage the cells and tissues of the infected organism directly by breaking down the cells for food. Others release toxins that travel throughout the body interfering with the normal activity of the host. Vaccine: preparation of weakened or killed pathogen. Antibiotics: compounds that block the growth and reproduction of bacteria

Viral Diseases Like bacteria, viruses produce disease by disrupting the body’s normal equilibrium. Viroid; single stranded RNA molecules that have no surrounding capsids. Prions: protein infectious particles.

Activity Take out a sheet of paper Write your prediction. On one side make a venn diagram On the other side make two boxes Activity Venn Diagram- Your going to write the differences and similaries of bacteria and virusesbacteria and virus Two boxes- Your going to cut and paste which picture goes under virus and bacteria categories Bacteria Virus Bacteria Virus