LESSON 7: BACTERIAL MORPHOLOGY AND FINE STRUCTURE

Question 1

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. Bacteria come

Question 2

usually ound but can either be oval, elongated, spherical or elliptical shape. Either they may remain as a single cell or
may aggregate together for various configurations

Answer 2

Cocci

Question 3

Cocci :

Answer 3

a. Monococcus:
b. Diplococcus:
c. Streptococcus:
d. Tetracoccus:
e. Staphylococcus:
f. Sarcina:

Question 4

: represented by single, discrete round cell.

Answer 4

Monococcus

Question 5

: the cell of the divides but the cells remain
attached to each other.

Answer 5

Diplococcus

Question 6

: here the cells divide repeatedly in one plane to form chain
of cells.

Answer 6

Streptococcus

Question 7

: this consists of four round cells, which divide in two planes at
right angles to one another and remain in group of four.

Answer 7

Tetracoccus

Question 8

: here the cells divided into three planes forming a
structured like bunches of grapes giving and irregular configuration.

Answer 8

Staphylococcus

Question 9

: here the cells divided into three planes forming a
structured like bunches of grapes giving and irregular configuration.

Answer 9

Staphylococcus

Question 10

: 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

Answer 10

F. Sarcina

Question 11

: these are rod shaped or cylindrical bacteria which either remain singly or
in pairs.

Answer 11

Bacilli

Question 12

Bacilli 3

Answer 12

a. Diplobacilli:
b. Streptobacilli:
c. Coccobacilli:

Question 13

appear in pairs after cell division

Answer 13

Diplobacilli

Question 14

occurs in chain after cell division

Answer 14

Streptobacilli

Question 15

: oval shaped similar

Answer 15

Coccobacilli

Question 16

: curved, comma shaped bacteria and represented by a single genus.

Answer 16

Vibro

Question 17

: spiral or spring like with multiple curvature and terminal flagella with
fairly rigid bodies.

Answer 17

Spirilla

Question 18

: helical and flexible which move by means of axial filaments
resembling flagella but contained within an external sheath

Answer 18

Spirochete

Question 19

BACTERIAL Structure

Question 20

BACTERIAL Structure

Question 21

: (meaning sugar coat) are viscous substances that surrounds the cell
composed of polysaccharide, polypeptide or both

Answer 21

Glycocalyx

Question 22

Functions

Answer 22

: (1) enables bacteria
to survive by attaching to surfaces, example: Streptococcus mutans attaches tothe surface of the teeth and cause dental carries,

(2) bacterial source of energy
when supply is low, and

(3) protection to hosts cell by attaching to surface hence
preventing the movements of nutrients out of cell during dehydration.

Question 23

Glycocalyx
It come in two forms:

– 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,

Answer 23

(a.) capsule form

Question 24

form – the substance in unorganized and is loosely attached to the cell wall

Answer 24

b.) slime layer

Question 25

: (singular: flagellum, meaning whip) are long filamentous appendages that propel bacteria.

Answer 25

Flagella

Question 26

Three basic parts: fragella

Answer 26

(1) filament: long outermost part that contains flagellin arranged in helix, (2) hook: where filament is attached to, and (3) basal body: anchors the flagellum to the cell wall and plasma membrane. The flagella move by rotating from the basal body either in clock

Question 27

Its movement is termed motility which is can be presented in different patterns:

Answer 27

(a) run or swim: bacterium moves in one direction, (b) tumbles: periodic abrupt or random interruptions to run or swim and (c) swarm: rapid wavelike movement

Answer 28

H

Question 29

: also called endoflagella present in Spirochetes like Borrelia burgdorferi that causes Lyme disease

Answer 29

Axial filaments

Question 30

: is a type of a protein called pilin. It is a numerous hair like appendages that surrounds the bacterium and helps to attach to hosts surfaces. Pili: is another type of the protein pilin but is only presented in one or two per bacterium. Pili helps bacterial cell to prepare DNA transfer from one cell to another.

Answer 30

Fimbriae

Question 31

: is another type of the protein pilin but is only presented in one or two per bacterium. Pili helps bacterial cell to prepare DNA transfer from one cell to another.

Answer 31

Pili

Question 32

is a semi rigid structure protects the interior of the cell from the outside environmen

Answer 32

The bacterial cell wall

Question 33

6 Functions of cell wall

Answer 33

: (1) prevents rupture of the cell, (2)maintain shape of cell, (3) anchors flagella, (4) contributes to the virulence of the bacteria, (5) site of action of some antibiotics, and (6) the chemical composition of cell is used to differentiate types of bacteria.

Question 34

bacterial cell wall is primarily composed of network of peptidoglycan (also called murein), either alone or in combination with other substances

Answer 34

Peptidoglycans (also called murein),

Question 35

have multiple layers of peptidoglycan in its cell wall for a thick rigid structure

Answer 35

Gram positive bacteria

Question 36

It contains -- which provide the antigenic capacity of the bacteria making it possible to identify it upon laboratory tests

Answer 36

teichoic acids

Question 37

has a thin layer of peptidoglycan making it very susceptible to mechanical breakage or environmental degradatio

Answer 37

the cell wall of Gram negative bacteria

Question 38

Cell wall (outer portion) Is composed of 3

Answer 38

1. Lipopolyssachrides 2. Lipoprotein 3. Phospholipids

Question 39

There are bacteria that is composed of higher percentage of ---- in their cell walls than peptidoglycan (Mycobacterium sp, Nocardia sp.), which prevents reaction to Gram stain

Answer 39

mycolic acid

Question 40

it can be stained with a carbolfuchsin which resist removal with acid alcohol thus called

Answer 40

acid-fast bacteria

Question 41

Structures internal to the cell wall

Question 42

Plasma membrane: underlying the cell wall is a thin layer of plasma membrane composed mainly of phospholipids arranged in two rows called

Answer 42

lipid bilayer

Question 43

The outer surfaces of the lipid bilayer (polar heads) are

Answer 43

hydrophilic or water-loving

Question 44

while the inside of the bilayer (nonpolar tails) are

Answer 44

hydrophobic or water-fearing

Question 45

Functions OF PLASMA MEMBRANE

Answer 45

(1) entry/exit of substances in cell by selective permeability (2)protect and lubricate the cell (3) cell-to-cell interactions, and (4) breakdown of nutrients and energy production.

Question 46

The movement of materials/substances across the membrane can be either Passive or Active processes

Question 47

PASSIVE INCLUDES:

Answer 47

1. Simple diffusion 2. Facilitated diffusion 3. Osmosis

Question 48

movement of molecules from high concentration to low concentration

Answer 48

1) Simple diffusion:

Question 49

: same with simple diffusion but substances are transported across the membrane via transporter

Answer 49

(2) Facilitated diffusion:

Question 50

: movement of a solvent molecule (water) from high concentration to low concentration via a selectively permeable membran

Answer 50

(3) Osmosis

Question 51

Active process includes:

Answer 51

1. Active transport 2. Group translocation

Question 52

: the cell uses energy to transport a substance from lower to higher concentration without altering the substance

Answer 52

(1) Active transport

Question 53

: a special type of active that alters the substance being transported across a membrane.

Answer 53

(2) group translocation

Question 54

the substance inside the plasma membrane composed mainly of water and other substances like proteins, carbohydrates or lipids.

Answer 54

Cytoplasm

Question 55

also called nucleoid, located in the cytoplasm of a bacterial cell contains double-stranded DNA each for the bacterial chromosome and plasmid.

Answer 55

Nuclear Area

Question 56

present in both prokaryotic and eukaryotic cells and serve as sites for protein synthesis

Answer 56

Ribosomes

Question 57

Ribosomes have 2 subunits:

Answer 57

30S (small and contains one molecule of ribosomal [rRNA] in bacteria), 50S subunit (larger and contains two molecules of rRNA in bacteria).

Question 58

Ribosomes in bacteria are called

Answer 58

called 70S ribosomes.

Question 59

Inclusions: these are reserve deposits of

Answer 59

(1) metachromatic granules (used in ATP synthesis), (2) polysaccharide granules, (3) lipid inclusions, (4) sulfurgranules (energy reserve), (5) carboxysomes (for carbon dioxide fixation) (6) gasvacuoles (maintain buoyancy) (7) magnetosomes: are iron oxide that acts like magnet to move until attachment site

Question 60

: these are specialized resting cell formed internal the cell membrane when a bacterial cell goes into vegetative state (active cell that undergoes metabolism) in a process called sporulation

Answer 60

Endospores