General Flashcards
Prokaryotes
No nuclear membrane or nucleoli
Simple Flagella
Cell Wall- chemically complex
No carbohydrates within plasma membrane
Small Ribosomes
Single circular chromosomes without histones
partakes in binary Fission, transfers DNA fragments only for sexual reproduction
Eukaryotes
True nucleus with a membrane membrane enclosed organelles Complex flagella cell wall (if present) simple Carbohydrates and sterols present in plasma membrane contains cytoskeleton Larger Ribosomes Mitosis and Meiosis
Prions
Infectious Proteins
no cell wall
Viruses
Genetic material wrapped in a membrane that needs a host to survive
no cell wall
can have spikes and/or capsid
RNA or DNA core
Shapes
Cocci Bacilli Coccobacilli pleiomorphic spirochetes
Gram Positive
after staining= purple Thick cell wall recognizable by the immune system resistant to lysis but can be opsonized Teichonic acid and Lipoteichoic acids located on cell wall
Gram Negative
After staining= red thin cell wall outer and inner membranes Lipopolysaccharide has porins
Lipopolysaccharide
Lipid A- endotoxin activity
Oligosaccharide-
O antigen- highly variable across different species
Mycobacteria
similar to gram positive
cell wall made of fatty acids and waxes
Capsule
can be either gram positive or negative
inhibits complement pathway and phagocytosis
mechanism of resistance
examples: S. agalactiae, S. pneumoniae, N. meningitides, K. pneumoniae, and H. influenza,
Obligate aerobes
need oxygen
Obligate anaerobes
Dont need oxygen
can’t reproduce in the presence of oxygen
Facultative
can live with or without oxygen
usually gram positive
Spores
Gram positive rods only inactive resistant to heat contain dipicolinic acid ex: clostridium and B. anthracis, B. subtilis, and B. cereus
flagella
projections for motility
sex pili
projections for conjugation- exchange of genetic material
common pili
projections for attachment
Plasmids
small DNA molecule that is physically separate from, and can replicate independently of, chromosomal DNA within a cell
usually small circular, double-stranded DNA
Spikes
Proteins projections that allow a virus to attach to and penetrate cells
Capsid
envelope that helps virus survive longer outside of a host
Replicative cycle of Virus
- Attachement to cell
- entry to cell (endocytosis)
- uncoating (dump material into cell)
4a. replication of RNA/DNA
4b. synthesis of proteins - Assembly
- Release
+ RNA
Can directly make proteins
- RNA
Has to make a template before proteins can be made
Bugs that can avoid phagocytosis
Strep. pneumoniae H. influenzae Nesseria meningitidis klebsiella pneumoniae salmonella typi