BACTERIA
Although tiny, prokaryotes differ greatly in their genetic traits,
, their modes of nutrition, and their habitats.
A mutation in the DNA of a single bacterium can confer ________ to an antibiotic. Cells with the mutant gene have a selective advantage when the antibiotic is present. Mutant cells take over the population when the normal cells _____
-resistance -die
Many bacteria have an outer covering of polysaccharides called a ______ that protects the cell against drying, pathogens, or harsh chemicals.
Capsule
One of the ways in which archaea differ is the make up of their -----. Archaeal cells walls do --- contain peptidoglycan
Cell wall not
causes the sexually transmitted infection called chlamydia.
Chlamydia trachomatis
The lipids and proteins of archaeal cell walls _____ from those of bacterial cell walls.
Differ
Prokaryotic Habits
Different prokaryotic species live in different environments. Temperature requirements range from 0°C to 110°C. Most prokaryotic species grow best at a neutral pH.
Prokaryotes
Domain Bacteria Domain Archaea
Eukaroytes
Domain Eukarya
Some Gram-positive bacteria can form a thick-coated, resistant structure_______, when environmental conditions become harsh
Endospores
Human diseases may result from ____ or _____ produced by bacteria or from the destruction of body tissues.
Endotoxins Exotoxins
Members of this group include bacteria of the genus Rhizobium, the genus Agrobacterium, and the bacterium
Escherichia coli
Many prokaryotes have long _____ that allow the prokaryotes to move toward food sources or away from danger.
Flagella
Spirochetes can live ____ or as pathogens. Pathogenic spirochetes include Treponema pallidum, the causative agent of syphilis, and Borrelia burgdorferi, which causes Lyme disease.
Freely
Not all of the bacteria in this group are Gram-positive. Biologists place a few species of Gram-negative bacteria in this group because these species are _________similar to Gram-positive bacteria
Genetically
Most species of bacteria are classified into two categories based on the structure of their cell walls as determined by a technique
Gram Strain
have a thin layer of peptidoglycan in their cell wall, and they appear reddish-pink under a microscope after the Gram-staining procedure.
Gram-negative bacteria
have a thick layer of peptidoglycan in their cell wall, and they appear purple under a microscope after the Gram-staining procedure
Gram-positive bacteria
"salt-loving" archaea that live in very salty environments such as the Great Salt Lake and the Dead Sea
Halophiles
2 major domains
archaea and bacteria
Most prokaryotic cells have a
cell wall
Spirochetes are Gram-negative, spiral-shaped bacteria that move by means of a _____. some are
corkscrew-like rotation. Aerobic
Members of this group include
include the streptococcal species, Clostridium botulinum, Bacillus anthracis, and members of the genus Mycobacteria.
The number of certain bacterial diseases has increased because of the _____ in the number of antibiotic resistant bacteria, the movement of people into previously untouched areas, and _____ travel.
increase Global
Prokaryotic DNA is a single closed ------ of double-stranded DNA attached at one point to the cell membrane.
loop
single-celled organisms that do not have a membrane-bound nucleus, and can live in nearly every environment on Earth.
prokayotes
Foodborne illnesses can be avoided by selecting, storing, cooking, and handling food ______ Frequent hand washing in hot, soapy water is also very important
properly
Most bacteria have one of three basic shapes
rod-shaped, sphere-shaped, spiral-shaped.
Bacteria are also classified
their biochemical properties and evolutionary relationships.
Archaea differ
type of lipids in their cell memebrane. Also,archaeal genes do NOT contain introns.
Based on genetic differences, prokaryotes are grouped in two domains
: Domain Archaea and Domain Bacteria.
Archaeal Groups
Archaeal groups include methanogens, halophiles, and thermoacidophiles.
Once called blue-green algae, cyanobacteria are now known to be _______ because they lack a membrane-bound nucleus and chloroplasts.
Bacteria
Many species of bacteria are used to produce and process different foods, to produce industrial chemicals, to mine for minerals, to produce ______, and to clean up chemical and oil spills. Biologists have learned to harness bacteria to recycle compounds in a process called ___________, which uses bacteria to break down pollutants
Insecticides Bioremediation
convert hydrogen gas and carbon dioxide into methane.They can be found in the ----- of organisms such as cattle and termites.
Methanogens Intestines
Gram-negative coccoid pathogens of the group Chlamydia live only inside animal cells. The cell walls of chlamydia do __ have peptidoglycan.
Not
Bacteria cell walls contain
Peptidoglycan
is a protein-carbohydrate complex found in bacterial cell walls that make their cells walls rigid.
Peptidoglycan
short, hairlike protein structures on the surface of some bacteria that help bacteria connect to each other and to surfaces, such as those of a host cell
Pili
Along with a single main chromosome, some prokaryotes have ______, which are small, circular, self-replicating loops of double-stranded DNA.
Plasmid
Bacteria and archaeal cell membranes and lipid bilayers that have
Protein
one of the largest and most diverse groups of bacteria, and contain several subgroups that are extremely diverse.
Proteobacteria
A compound made of if unusual lipids and amino acids
Pseudomurein
Archaeal cell walls DO NOT have PEPTIDOGLYCAN ;Instead they have
Pseudomurein
Bacteria occur in many
Shapes and Sizes
live in very hot, acidic environments, such as the hot springs of Yellowstone National Park
Thermoacidophileds