280 likes | 1.02k Views
Types of Heterotrophic Nutrition. Methods of Feeding. Saprophytic Nutrition feed on dead organic matter, get energy from it, and recycle it back into the environment. decomposers. Parasitism organism (parasite) feeds off of another (host) at the expense of the host. Predation
E N D
Methods of Feeding • Saprophytic Nutrition • feed on dead organic matter, get energy from it, and recycle it back into the environment. • decomposers. • Parasitism • organism (parasite) feeds off of another (host) at the expense of the host. • Predation • - organism (predator) hunts, kills, and eats another organism (prey). • Scavenging • feed on organisms killed by something else.
Bacteria Kingdoms Archaebacteria & Eubacteria (Formerly Monera)
What are Bacteria? • Bacteria are PROKARYOTES • The smallest known living cells They are found everywhere!! Bacteria on head of a pin Starr, 317 Did you know? There are over 80 species of bacteria in your mouth! Bacteria in dental plaque microbeworld.org
Obtaining Energy • Autotrophs (make energy) • Photoautotrophs- capture energy from light • Ex- cyabobacteria • Chemiautotrophs- obtain energy from chemical reactions with inorganic molecules (ammonia, hydrogen sulfide, nitrites, sulfur, Iron) • Ex. Ocean vent bacteria
Obtaining Energy cont… • Heterotrophs- most bacteria obtain their energy from organic molecules • These bacteria are often feeding in, on and around us… • Some bacteria are photoheterotrophs • Capture sunlight and digest organic molecules
Releasing Energy • Bacteria can use both cell respiration and fermentation • Many bacteria have different oxygen requirements: • Obligate aerobes- must have oxygen for respiration • Facultative anaerobes- can function with or without oxygen • Obligate anaerobes- poisoned by oxygen (use fermentation)
Three basic shapes of Bacteria • Spherical – coccus • Rod – bacillus • Coiled - spirillum Schraer, 633
Coccus Spheres Cocci (plural) a variety of arrangements
Bacillus Cylindrical or rod-shape Bacilli (plural) Variations in cell arrangement Diplobacillus (paired)
Spirals Vibrio Spirillum Spirochete
Staphylo = clusters Strepto = chains Simple Colonies Staphylococcus wisc.edu Diplo = double Diplococcus cat.cc.md.us Streptobacillus
Many can MOVE Some have flagella- made of rope-like proteins, not microtubules. Some slide on a slimy secretion. Many can form dormant cells called endospores to survive harsh conditions. Salmonella www.iwate.jp Streptomyces spores
Bacterial Reproduction • Bacterial cells reproduce asexually through fission which is the splitting of a cell into two new cells.
Bacterial Reproduction cont… • Some bacteria utilize conjugation to exchange pieces of genetic information to increase variation • *Not considered sexual reproduction- not complete exchange of DNA, no offspring made