Lesson 7-9 Flashcards
(127 cards)
The size of most bacteria ranges from
0.2 μm (micrometer) to 2.0 μm
in diameter and from 2.0 μm to 8.0 μm.
usually round but can either be oval,
elongated, spherical or elliptical shape
Cocci
: represented by single, discrete round cell.
Monococcus
divides but the cells remain
attached to each other.
Diplococcus
c. : here the cells divide repeatedly in one plane to form chain
of cells.
Streptococcus
: this consists of four round cells, which divide in two planes at
right angles to one another and remain in group of four.
e.
Tetracoccus
: here the cells divided into three planes forming a
Staphylococcus
structured like bunches of grapes giving and irregular configuration.
these cells divide in three planes but they form a cube like
configuration consisting of eight or sixteen cells but they have a regular
shape.
Sarcina
these are rod shaped or cylindrical bacteria which either remain singly or
in pairs.
Bacilli
appear in pairs after cell division
Diplobacilli
occurs in chain after cell division
Streptobacilli
: oval shaped similar to cocci
Coccobacilli
: curved, comma shaped bacteria and represented by a single genus.
Vibro
: spiral or spring like with multiple curvature and terminal flagella with
fairly rigid bodies.
Spirilla
: helical and flexible which move by means of axial filaments
resembling flagella but contained within an external sheath
Spirochete
are viscous substances that surrounds the cell
composed of polysaccharide, polypeptide or both.
Glycocalyx
Glycocalyx is composed of what?
Polysaccharide or polypeptides or both
Function of glycocalyx
-enables bacteria
to survive by attaching to surfaces
-bacterial source of energy
when supply is low
-protection to hosts cell by attaching to surface hence
preventing the movements of nutrients out of cell during dehydration
attaches to
the surface of the teeth and cause dental carries,
Streptococcus mutants
Two form of glycocalyx
Capsule form
Slime layer form
the substance is organized, is firmly attached to
the cell wall, and clinically contributes to the virulence (ability to cause disease) of
bacteria due to its capacity to evade phagocytosis by hosts cells
Capsule form
he substance in unorganized and is loosely attached to the cell wall
Slime layer form
are long filamentous appendages
that propel bacteria
Flagella