Chapter 27- bacteria and archea

Bacteria

Microscopic single-celled prokaryotic organisms that lack a membrane-bound nucleus and organelles.

Archaea

Microscopic single-celled prokaryotes that lack a membrane-bound nucleus, featuring unique membrane lipids and cellular chemistry, frequently found in extreme environments.

What do bacteria and archaea have in common?

Both are microscopic, single-celled, prokaryotic organisms that lack a membrane-bound nucleus.

Peptidoglycan

A polymer consisting of sugars and amino acids that forms a structural component of the bacterial cell wall.

Polysaccarides and protiens

Archaea cell wall is made of…

Gram staining

Bacteria species separated using a special stain

Gram-positive

colored by gram stains, simpler cell walls

Gram-negative

not affected by gram stains, complex cell walls

Endospores

can help cell structure. It copies chromosomes and surrounds them, stopping metabolism. (like hibernation)

Fimbraie

hair-like structures that help archaea stick to things

Pili

appendages that pull two cells together

Chemotaxis

movement pattern directed by chemicals

Flagellum

Bacterial flagellum parts

Motor, hook, and filament.

Exaptation

one function takes on a new function

Binary Fisson

bacteria reproduction. Cell divides into 2…then 4…and so on. Stops when the cell runs out of energy.

Reasons for genetic diversity

rapid reproduction, rapid mutation, and genetic recombination

Genetic recombination

the physical exchange of DNA segments between genetic materials

Transformation

foreign DNA picked up and incorporated

Transduction

carrying genes between host to cell

Conjugation

DNA transferred from two parent prokaryotes

Horizontal gene transfer

another species incorporated into a genome

R plasmids

a small, circular piece of DNA outside a bacterium's main chromosome that gives the cell resistance to antibiotics or other environmental poisons

Oxygen metabolism

the biochemical process by which cells use oxygen to convert nutrients into cellular energy

Obligate aerobes

cannot grow without oxygen

Obligate anaerobes

poisoned by oxygen

facultative anaerobes

use oxygen, but can use other things

Nitrogen metabolism

the set of biochemical processes that convert and use nitrogen-containing compounds across living organisms, while safely removing or recycling toxic nitrogen waste

Cooperation

colonies of prokaryotes

Anabacteria

can use photosynthesis

Proteobacteria

large, diverse, gram-negative bacteria

Extremorphiles

archaea that live in extreme environments