LP2

– Bacteria

– Archaea

• -astonishing genetic diversity
• -Smallest of the unicellular organisms
• -some in colonies
• -thrive almost everywhere (too hot and cold)
• -no membrane bound nucleus
• -many division = many mutations

Cocci (spherical)

Bacilli (rod)

Spirillum (spiral)

–Maintains cell shape

–Provides physical protection

–Prevents the cell from bursting in a hypotonic environment

more solutes inside cell than outside so cell gains water

cell shrinks away from wall

Autotrophs (oxidation of nonorganic)

classifies bacteria into two groups based on cell wall composition

Gram-negative tend to be more pathogenic

• -a sticky layer of polysaccharide or protein (covers cell wall)
• -Allows cell to adhere to stuff
• -Protects pathogenic bacteria from immune system

• -Some Bacteria
• -ability to move toward or away from certain stimuli

• -usually lack complex compartmentalization
• -Some prokaryotes do have specialized membranes that perform metabolic functions

• where typical prokaryotic genome (ring of DNA
• that is not surrounded by a membrane) is located

Prokaryotes reproduce quickly by binary fission

Many prokaryotes form endospores, which can remain viable in harsh conditions for centuries

• transformation
• transduction
• conjugation

• cell can take up and incorporate foreign DNA
• from the surrounding environment

the movement of genes between bacteria by bacteriophages (viruses that infect bacteria)

the process where genetic material is transferred between bacterial cells

Sex pili allow cells to connect and pull together for DNA transfer

A piece of DNA called the F factor is required for the production of sex pili

The F factor can exist as a separate plasmid or as DNA within the bacterial chromosome

carry genes for antibiotic resistance

• Photoautotrophy (plants)
• Chemoautotrophy
• Photoheterotrophy
• Chemoheterotrophy (people)

Require oxygen

Can survive with or without oxygen

Are poisoned by oxygen

Prokaryotes can metabolize nitrogen

In some prokaryotic species, metabolic cooperation occurs in surface-coating colonies

• mutualism (both benefit)
• commensalism (only one benefits but other not harmed)

the use of organisms to remove pollutants from the environment

• Protists are an extremely diverse assortment of eukaryotes
• Most protists are unicellular, though some are colonial or multicellular

• Sexual
• Asexual
• Both
• Variations thereof

Flagella with a unique internal crystalline or spiral rod

• Includes:
• Predatory heterotrophs
• photosynthetic autotrophs
• pathogenic parasites

• mixotrophic
• one or two flagella that emerge from a pocket at one end of the cell
• Eyespot & light detector that enhance photosynthetic ability

Characterized by membrane-bounded sacs (alveoli) just under the plasma membrane

“hairy” and smooth flagella

• Includes:
• several groups of heterotrophs
• certain groups of algae

• Some of the Amoebas (move and feed by means of pseudopodia)
• Threadlike pseudopodia

• lobe-shaped, rather than threadlike, pseudopodia
• Predators decomposers, & parasites (amoebic dysentery)

• closest relatives of land plants
• Complex life cycles (both asexual & sexual)

• heterotrophs but do not ingest their food
• secrete exoenzymes into their surroundings that break down complex molecules and then absorb the remaining smaller compounds

• Decomposers
• Parasites
• Mutualistic symbionts

consist of mycelia (networks of branched hyphae adapted for absorption)

networks of branched hyphae adapted for absorption

mutually beneficial relationships between fungi and plant roots

propagate themselves by producing vast numbers of spores, either sexually or asexually

• Cell fusion (plasmogamy)
• Nuclear fusion (karyogamy)

• molds
• yeasts

Defined by the production of sexual spores in saclike asci, which are usually contained in fruiting bodies (called ascocarps)

Some species live with cyanobacteria or algae as lichens

• Includes:
• mushrooms and shelf fungi

Defined by a clublike structure called a basidium, a transient diploid stage in the life cycle

• Decomposers
• Fungi form symbiotic relationships with plants, algae, and animals
• –Mycorrhizae

–Digestion for many animal species

–Lichens

• About 30% of known fungal species are parasites, mostly on or in plants
• Some of the fungi that attack food crops are toxic to humans