3. Composition of microbial world 2 Flashcards
1
Q
Prokaryotes
A
- bacteria, archea
– similar in size and shape - lack membrane-bound nucleus
- lack membrane-bound organelles
2
Q
Bacteria
A
- prokaryotic
- peptidoglycan cell walls
- gram-positive; gram-negative
– structure of cell wall
– gram-negative can be antibiotic resistent
3
Q
what are peptidoglycan cell walls
A
- combination of peptide bonds & carbohydrates
– peptide (amino acids)
– glycan (sugars) - attacked by pennisylin
4
Q
what are the arrangements of bacteria cells
A
- coccus (spherical)
- bacillus (rod shaped)
- spirillium (sprial)
- vibrio (crescent like)
- spirochete
- filamentous bacteria
- cells will clump together if growth conditions are not good
– formations depends on growth conditions
5
Q
how to bacteria reproduce
A
- binary fission
– daughter cells identical to mother
6
Q
how does binary fission work
A
- replication of DNA
– duplication of chromosome - cell growth
– continued cell growth of cell - segregation of DNA
- splitting of cells
– division into two cells
7
Q
what are archaea
A
- prokaryotic
- diverse physiology
- range of single cell morphologies to filaments and even aggregates (0.1 - 15 micrometers)
- hard to culture for biologists in lab conditions
8
Q
how do archaea have diverse physiology
A
- found to live in extreme environments
– hot springs
– geysers
– gamma rays / UV radiation
9
Q
what do archaea include
A
- methanogens
- extreme halophiles
- extreme thermophiles
10
Q
how do archaea differ from bacteria
A
- cell wall structure
– lacks peptidoglycan - unique membrane lipid structure
11
Q
how is archaea membrane structure unique
A
- unique lipid structure
- side chains connected to glycerol backbone by ether bonds
– instead of ester - side chains branched
– phytanyl sidechain
– sometimes form monolayer membrane - ether linkages vs. ester linkages
12
Q
what are eukaryotes
A
- multicellular / unicellular
- true membrane-bound nuclei
- DNA orgaises into chromosomes
- cell reproductions by mitosis and meiosis
- specific cellular functions in different organelles
– eg. mitochondria respiration
– eg. chloroplast photosythesis
13
Q
how are eukaryotic cellular functions specific in different organelles?
A
- specific cellular functions in different organelles
– eg. mitochondria respiration
– eg. chloroplast photosythesis
14
Q
what are fungi
A
- multi/unicellular
- saprophytes
- rigid cell walls (non-motile)
- filamentous (hyphae)
- secrete degradative enzymes into environments —- cellulases
– proteases
– amylases
15
Q
what are fungi cell walls made up of
A
- chitin
– complex polysaccharide
