Microorganisms & Bacteria

Section 1.1-4

Microorganisms

• Very small, living things that you need a microscope to see

• Three kingdoms include microorganisms– Archaea

– Bacteria

– Protists

Characteristics of living things

• Organization (cells)• Growth• Reproduction• Response

Needs of Living Things

• Energy• Materials• Living space

Viruses

• Genetic material enclosed in a protein shell• Viruses are not living things– Not as complex as a cell– Do not take in energy– Do not grow once formed– Cannot reproduce by themselves

H1N1 virus

Viruses

• Multiply inside living things (hosts)– Attachment– Injection– Production– Assembly– Release

Host is usually damaged or destroyed

Bacteria

• Simplest kind of life on Earth– Single celled– Do not contain a nucleus

• Classified by shapeSpiral Rod Round

Bacteria

• Producers - make own food– Contain chlorophyll – Perform photosynthesis

• Decomposers – break down dead or decaying material

– Recycles material

• Parasites – live in or on other organisms

Bacteria

• Helpful– Release oxygen into the air– Recycle materials– Clean up sewage and oil– Make materials useful (Nitrogen fixing)

• Harmful– Cause disease

Archaea

• Single-celled organisms that can survive in the largest range of environments. Do not contain a nucleus.– Methanogens – produce natural gas. Can not live

in oxygen

– Halophiles – live in very salty water

– Thermophiles – live in extreme heat or cold

Protists

• Organisms with a nucleus that do not belong to animal, plant or fungi kingdom– Most live in water– Most are single-celled– Have simpler structures

Protists

• Algae – plant-like protists (photosynthesis)

• Plankton – organisms that drift (not swim) in water

• Protozoa – animal-like protists (eat others)• Decomposers – absorb food from

environment (molds)