Prokaryotic cell - topic 5 Flashcards
Prokaryote
a group of incredibly diverse species that are mostly unicellular, microscopic organisms. They are found almost everywhere.
Divided into two domains: archaea and bacteria
Cell wall
a protective layer external to the plasma membrane in the cells
Capsule
neatly organized carbohydrate
Gram stain
used to identify the composition of a cell wall into gram-positive (purple) or gram-negative (red)
Coccus
cell is circle shape
staphylo-
cell arrangement in clusters
obligate aerobes
require O2 for cellular respiration
Nucleoid region
where the DNA is in cells that do not have a nucleus.
Binary fission
the reproduction of cells in prokaryotes
Slime layer
is an unorganized & loose (slimy) carbohydrate (sticky & slimy)
Endospore
is a little bit of cytoplasm, DNA, & a think coat of peptidoglycan.
Can remain viable in harsh conditions and can be produced in response to changing conditions.
Bacillus
Cell shaped like rod
Strepto-
Cells are in a chain arrangement
Obligate Anaerobes
are poisoned by O2 and use fermentation or anaerobic respiration
Chromosomes
a cellular structure carrying genetic material. Found in the nucleus of prokaryotic cells
Conjugation
= sex = exchange of DNA (no reproduction involved here)
Fimbriae
allow prokaryotes to stick to a surface or other cells in a colony (also called attachment pili)
Flagella
allow motile bacteria to move toward or away from certain stimuli. Made of long chains of proteins called flagellin.
Spirillium/ spirilli / spirochaetes
Cell is shaped as a spiral
Pathogen
An organism, virus, viroid, or prion that causes disease
Bacteria as pathogens
are a major cause of human death, and disease and cause infections
Facultative anaerobes
Can survive with or without O2
Plasmid
A small, circular, double- stranded DNA molecule that carries accessory genes separate from those of a bacterial chromosome.
F+ cells
containing the F plasmid function as DNA donors
F- cells
without the F plasmid functions as DNA recipients
Peptidoglycan
A network of sugar polymers cross-linked by polypeptides (located in the bacteria cell wall)
pilli (pilus)
In bacteria, a structure that links one cell to another at the start of conjunction; also known as a sex pilus or conjunction
Endoflagella
Found in spirochaetes. Used as movement, the entire cell corkscrews by a twisting motion through its environment.
Diplo-
Cells are arranged in pairs
E. coil
bacterial species that normally lives in the lower intestine of warm-blooded animals.
Is gram negative, mostly harmless
Pencillin
Antibacterial drug that inhibits cell wall synthesis (effects peptidoglycan)
