BACTERIAL CELL STRUCTURE, PHYSIOLOGY, METABOLISM AND GENETICS

Question 1

Dutch biologist/lens maker
Ø Discovered beasties in a water droplet in his homemade
microscope
Ø First to study microorganisms
Ø “Father of protozoology and bacteriology”

Answer 1

ANTON VAN LEEUWENHOEK

Question 2

4 MICROBES ARE:

Answer 2

Bacteria, Fungi, Parasites, Viruses

Question 3

Unicellular organisms that lack a nuclear membrane and true
nucleus

Ø Classified as Prokaryotes, having no mitochondria, ER, or Golgi bodies

Ø Absence of these structures differentiates them from
Eukaryotes

Answer 3

BACTERIA

Question 4

Ø Eukaryotic parasites exist as unicellular organisms of
microscopic size, whereas others are multicellular.

Ø Protozoa are unicellular organisms within the kingdom
Protista, which obtain their nutrition through ingestion.

Ø Motile or nonmotile

Answer 4

PARASITES

Question 5

Categorized by their locomotive structures:
– _____ (whiplike)
– _____ (false feet)
– ____ (eyelash)

Answer 5

FLAGELLA
PSEUDOPODIA
CILIA

Question 6

Multicellular parasites (e.g. tapeworm) may be as long as ____ to ___ meters

Answer 6

7 - 10 METERS

Question 7

Heterotrophic eukaryotes that obtain nutrients through
absorption

Answer 7

FUNGI

Question 7

Bodies of multicellular fungi are composed of filaments called

Answer 7

HYPHAE

Question 8

which interweave to form mats called

Answer 8

MYCELIA

Question 8

filamentous forms that can reproduce sexually and asexually

Ø Certain fungi can assume both morphologies (yeast and
hyphae/mycelial forms)

Ø Yeast at incubator or human temperature

Ø Filamentous form at room temperature

Answer 8

MOLDS

Question 9

produce systemic diseases

Answer 9

DIMORPHIC FUNGI

Question 10

are the smallest infectious particles (virions);

Ø they cannot be seen under an ordinary light microscope

Ø Neither prokaryotic nor eukaryotic

Ø Effects can be seen as inclusions, rounding up of cells, and syncytium (cell fusion of host cells into multinucleated infected forms)

Answer 10

VIRUSES

Question 11

A virus that infects and possibly destroy bacterial cells is known as a ____.

Answer 11

BACTERIOPHAGE

Question 11

The orderly classification and grouping of organisms into taxa (categories)

Answer 11

TAXONOMY

Question 12

Involvesthree structured, interrelated categories:

Answer 12

1. Classification/Taxonomy
2. Nomenclature
3. Identification

Question 13

Naming assignments for each organism

Answer 13

NOMECLATURE

Question 14

based on susceptibility to specific bacterial phages.

Answer 14

PHAGE TYPING

Question 15

However, more recently, taxonomists have placed all
organisms into three domains that have replaced some kingdoms:

Answer 15

BACTERIA, ARCHAEA, EUKARYA

Question 16

are prokaryotic cells that
infect eukaryotic hosts. Targeting antibiotic action against unique prokaryotic structures and functions inhibits bacterial growth without harming eukaryotic host cells.

Answer 16

Pathogenic (disease-causing) bacteria

Question 17

Ø Bacteria do not contain a membrane-bound nucleus.

Ø Their genome consists of a single circular chromosome.

Ø This appears as a diffuse nucleoid or chromatin body (nuclear body), which is attached to a mesosome, a saclike structure in the cell membrane

Answer 17

CYTOPLASMIC STRUCTURE

Question 17

appear as highly refractile bodies in the cell. ____ are
visualized microscopically as unstained areas in a cell with the use of
traditional bacterial stains

Answer 17

SPORES

Question 18

consists of the membrane and structures surrounding the
cytoplasm.

Ø In bacteria, these are the cell membrane and the cell wall.
Some species also produce capsules and slime layers.

Answer 18

CELL ENVELOPE STRUCTURES

Question 19

is a phospholipid bilayer with embedded proteins that
envelop the cytoplasm

Answer 19

PLASMA MEMBRANE

Question 20

is a rigid structure that
maintains the shape of the cell and prevents bursting of the cell from the high osmotic pressure inside it.

Answer 20

CELL WALL

Question 21

3 SURFACE POLYMERS ARE:

Answer 21

1. Capsule 2. Slime layers 3. Cell Appendages

Question 22

The flagellum is the organ of locomotion.

Answer 22

CELL APENDAGES

Question 23

are exterior protein filaments that rotate and cause bacteria to be motile.

Answer 23

FLAGELLA

Question 24

also known as conjugation pili, are nonmotile,long, hollow protein tubes that connect two bacterial cells and mediate DNA exchange.

Answer 24

PILI OR PILUS

Question 25

are nonflagellar, sticky, proteinaceous, hairlike appendages that adhere some bacterial cells to one another and to environmental surfaces.

Answer 25

FIMBRIAE

Question 26

The nucleus of the eukaryotic cell contains the DNA of the cell in the form of discrete chromosomes

Answer 26

CYTOPLASMIC STRUCTURE

Question 27

They are covered with basic proteins called

Answer 27

HISTONE

Question 28

the most commonly used stain in the clinical microbiology laboratory. Ø It places bacteria into one of two main groups: gram-positive (blue to purple) or gram-negative (pink)

Answer 28

GRAM STAINS

Question 29

are used to stain bacteria that have a high lipid and wax content in their cell walls and do not stain well with traditional bacterial stains

Answer 29

ACID FAST STAINS

Question 30

a fluorochrome dye that stains both grampositive and gramnegative bacteria, living or dead. Ø It binds to the nucleic acid of the cell and fluoresces as a bright orange when a fluorescent microscope is used.

Answer 30

ACRIDINE ORANGE

Question 31

is a fluorochrome that binds to chitin in fungal cell walls. Ø It fluoresces as a bright apple-green or blue-white, allowing visualization of fungal structures with a fluorescent microscope. was the original “blueing” used in high- volume laundries to whiten yellow-appearing white cotton and other fabrics

Answer 31

CALCOFLUOR WHITE

Question 32

traditionally has been used to stain C. diphtheriae for observation of metachromatic granules. Ø It is also used as a counterstain in acid-fast staining procedures.

Answer 32

METHYLENE BLUE

Question 33

is used to stain the cell walls of medically important fungi grown in slide culture.

Answer 33

LACTOPHENOL COTTON BLUE

Question 34

is a negative stain used to visualize capsules surrounding certain yeasts, such as Cryptococcus spp

Answer 34

INDIA INK