-Archaea
-Bacterica
-Eukarya
domains of life
-Archaea
-Bacteria
Biologist classify prokaryotes into which two of the three domains?
prokaryotes
no membrane-bound nucleus or organelles - their DNA and some proteins are localized in the cytoplasm
Cocci
bacilli
spirilla
What are the three shapes of prokaryotes?
Cocci
What is "A"?
Bacilli
What is "B"?
Spirilla
What is "C"?
gram-positive
bacteria that have cell walls consisting of a thick peptidoglycan layer
-blue
-purple
what color(s) is/are gram-positive
-pink
-red
what color(s) is/are gram-negative
Gram-negative
bacteria that have cell walls consisting of a thin peptidoglycan layer, surrounded by an outer membrane containing lipopolysaccharides
gram-negative
is this gram-positive or gram-negative
gram-positive
is this gram-positive or gram-negative
-glycocalyx
-capusle
Bacterial cells walls may be coated with an external layer of polysaccharides (______________) that may be loosely associated (slime layer) or firmly attached (_____________)
Capsule
what is surrounding the cell?
flagellum
A bacterial ____________ consists of a helical fiber of protein that rotates in a socket in the cell wall and plasma membrane
-hydrogen
-sodium ions
the flagella Rotation is powered by a gradient of __________ or ____________
flagella
what is represented by this picture?
pili
Some bacteria and archaeans have rigid, hairlike shafts of protein (_________) extending from their cell walls
gram-negative
among bacteria. pili are characteristics primarily of gram-positive or gram-negative
sex pili
what types of pili allow bacterial cells to adhere to other cells, or transfer genetic material
Autotrophs
obtain carbon from CO2 (inorganic)
make their own food
Heterotrophs
obtain carbon from organic molecules
eat those who make their own food
chemotrophs
obtain energy by oxidizing inorganic or organic substances
use food source for energy
phototrophs
obtain energy from sun light
Chemoautotrophs
Obtain energy by oxidizing inorganic substances such as hydrogen, iron, sulfur, ammonia, nitrites, and nitrates
Use CO2 as their carbon source
Include many bacteria and most archaeans
chemoheterotrophs
Obtain energy by oxidizing organic molecules
Obtain carbon in organic form
Include most pathogenic and decomposing bacteria
Photautotrophs
Obtain energy from light (photosynthesis)
Use CO2 as their carbon source
Include cyanobacteria, green sulfur bacteria, and purple sulfur bacteria
photoheterotrophs
Obtain energy from light
Obtain carbon in organic form
Include green and purple nonsulfur bacteria
Aerobes
_____________ require oxygen for cellular respiration
obligate aerobes
_______________ cannot live without oxygen
Anaerobes
__________________ do not require oxygen to live
obligate anaerobes
________________________ are poisoned by oxygen - they survive either by fermentation or anaerobic respiration
Facultative anearobes
__________________ use O2 when it is present, but can live by fermentation under anaerobic conditions