Chapter 4- Functional Anatomy Of Rokaryotic And Eukaryotic Cells Flashcards
Glycocalyx
meaning sugar coat
substances that surround cells
Sticky glue surrounding eukaryotic and prokaryotic cells -the glue that hold the cells in place
external to the cell wall and composed of polysaccharide, polypeptie or both
also can protect a cell against dehydration and its viscosity may inhibit movement of nutrients out of the cell
Prokaryotes
-make up a vast group of unicellular organisms that include bacteria and archaea -the majority are bacteria -typically DNA is not enclosed w in a membrane & is usually a singular, circularly arranged chromosome -DNA not associated w his tones -generally lack organelles such as nuclei mitochondria and chloroplasts -their cell walls almost always contain the complex polysaccharide peptidoglycan -usually divide by binary fission
Binary fission
Where DNA is copied, & the cell splits into 2 cells
Eukaryotes
-DNA is found in the cells nucleus-which is separated from the cytoplasm by a nuclear membrane and the DNA is found in multiple chromosomes -the DNA is consistently associated e chromosomal proteins called histones and w non histones -have a # of membrane enclosed organelle, including mitochondria endoplasmic reticulum, golgi complex, lysosomes and sometimes chloroplasts - their cell walls, when present r chemically simple -cell % usually involves mitosis- the 2 cells produced are identical to each other
Coccus plural:cocci
bacterial cells shape-usually round but can b oval, elongated or flattened on the side
Spherical Meaning:berries Usually round but can b oval, elongated or flattened on the side; when they % to reproduce the cells can remain attached to one another
Bacillus plural:bacilli
Rod shaped Meaning:little rods or walking sticks
Spiral
Spiral
Diplococci
Cocci that remain in pairs after % are called diplococci
bacterial cells shape-usually round but can b oval, elongated or flattened on the side
Streptococci
Cocci that % and remain in chainlike patterns
bacterial cells shape-usually round but can b oval, elongated or flattened on the side
Tetrads
Cocci that % in 2 planes and Remain in groups of 4
bacterial cells shape-usually round but can b oval, elongated or flattened on the side
Sarcinae
Cocci that % in 3 planes and remain attached in cubelike groups of 8
bacterial cells shape-usually round but can b oval, elongated or flattened on the side
Staphylococci
Cocci that % in multiple planes and for grape like clusters or broad sheets
bacterial cells shape-usually round but can b oval, elongated or flattened on the side
single bacilli
appear as single rods
diplobacilli
appear in pairs after division
streptobacilli
occur in chains
coccobacilli
are oval and lloo so much like cocci that they are called coccobacilli
bacillus
refers to a bacterial shape// but when capitalized and italicized it refers to a specific genus
bacillus cells often form long, twiste chains of cells
vibrios
bacteria that look like curved rods
spirilla
singular- spirillum
have a helical shape, like a corkscrew and fairly rigid bodies
move by flagella- propeler like appendages
spirochetes
spirals are helical and flexible
they move by axial filaments- which resemble flagella but are contained w in a flexible exernal sheath
the shape of bacterium
is determined by heredity
monomorphic
genetically most bacteria are..
they maintain a single shape; environmental condtions can alter shape though
pleomorphic
bacteria w many shapes not just 1
capsule
if the glycocalyx substance is organized and is firmly attached to the cell wall
can b determined by using negative staining-halo
capsules often protect pathogenic bacteria from phagocytosis by the cells of the host
slime layer
if the glycocalyx substance is unorganozed and only loosly attatched to the cell wall
bacterial virulence
the degree to which a pathogen causes disease
extracellular polymeric substance (EPS)
a glycocalyx that helps cells in a biofilm attatch to their target environment and to eachother
protects the cells w in it, facilitactes communication among them and enables the cells to survive by attatching to various surfaces in their natural environment
flagella (has 3 basic parts)
singular-flagellum
some prokaryotic cells have
long filaments appendages that propel bacteria
3 basic parts: filament, hook, basal body
atrichous
(without projections)
bacteria that lack flagella
peritrichous
flagella may be…^
distributed over the entire cell
polar
flagella is..^
can also be monotrichous or lophotrichous or amphitrichous
polar: at one or both poles/ends of the cell
monotrichious: a single flagellum at one pole
lophotrichous: a tuft of flagella coming from one pole
amphitricious: flagella at both poles of the cell
motility
the ability of an organism to move by itself
enables a bacterium to move toward a favorable environment or away from an adverse one
run or swim
the movement…when bacteriam moves in one direction for a length of time
tumble
periodic, abrupt random changes in direction of bacterium movement
caused by a reversal of flagellar rotation
swarm
bacterium show rapid wavelike movement across a solid culture medium
taxis
chemotaxis
phototaxis
movement of a bacterium toward or away from a particular stimulus
chemotaxis: stimuli include chemicals
phototaxis: stimuli inclide light
