Characteristics Of Microorganisms

Question 1

Bacteria

Answer 1

Makes up a large group of one celled MO’s; vary in size shape, and arrangement of cells; grows best at 98.6 F in moist, Dark environment.

Question 2

Viruses

Answer 2

Small in size and cause fatal diseases; this MO can live and multiply only inside an appropriate host cell.

Question 3

Protozoa

Answer 3

Large group of one celled organisms; do not have a rigid cell wall; found in freshwater, marine habitat, and moist soil; small number, are responsible for intestinal infections of humans and other invade, the blood, lungs, liver, or brain.

Question 4

Fungi

Answer 4

Mushrooms, yeast, and mold; oral candidiasis is a common form of this group, and mos found in the dental office.

Question 5

Prokaryotic cells

Answer 5

Primitive cells
No internal membrane
No nucleus
Example: bacteria

Question 6

Eukaryote cells

Answer 6

Complex cells
With internal membranes
Have a nucleus
Example: Protozoa, algae, fungi, plants, and animals.

Question 7

Flagella

Answer 7

Long, thin extension that provides mobility. (propeller).

Question 8

Frimbiae, pili

Answer 8

Hair-like projections with fine short appendages that allow bacteria to adhere.

Question 9

Cytoplasmic membrane

Answer 9

Regulates amount of molecules entering or leaving a cell.
Surrounds the cytoplasm; transport nutrients; energy metabolism.
Composed of lipids and proteins.
Anti-microbial agents, handwashing agents at the mouth rinses kill or inhibit the growth of bacteria by acting on the cytoplasmic membrane.

Question 10

Mesosomes

Answer 10

Present mostly in gram-positive bacteria
At inward folding of the cytoplasmic membrane.

Question 11

Cytoplasm

Answer 11

Contained within cytoplasmic membrane.

Question 12

Cell wall

Answer 12

Gives cell its shape; rigid; protection from Mechanical damage.

Question 13

Outer membrane of Gram-negative bacteria

Answer 13

Contains endotoxin; transporting nutrients.
When endotoxin is released from bacteria present in the body, it can cause damage to nearby body cells.

Question 14

Capsule

Answer 14

Gelatinous covering produced by the cytoplasmic membrane.
Protection from drying, antiphagocytic; attachment to surfaces.
The presence of capsules reduces the ability of WBC to surround in golf and destroy the bacterium through phagocytosis.

Question 15

Granules

Answer 15

Function as an energy reserve.

Question 16

Ribosomes

Answer 16

Contain RNA and proteins (proteins synthesis).

Question 17

Nucleoid

Answer 17

Contains DNA
Is embedded in the cytoplasm.

Question 18

Endospores

Answer 18

Thick wall-like structure
One of the most resistant forms of life against heat, drying and chemicals.
Defence mechanism /protection against adverse conditions.

Question 19

Plasmids

Answer 19

Extra chromosomal, DNA
Give ability of bacteria to grow by being resistant to physical and chemical agents and antibiotics.

Question 20

Cilia

Answer 20

Provides movement and permits, faster mobility than flagella.

Question 21

Plasma (cytoplasmic) membrane

Answer 21

Permits movement of molecules across the membrane by active and passive transport; endocytosis and exocytosis occurs at the site.

Question 22

Endocytosis

Answer 22

Taking in of matter

Question 23

Exocytosis

Answer 23

Contant released to exterior

Question 24

Endoplasmic reticulum

Answer 24

Fluid filled channels that synthesize lipids (smooth) and proteins (rough)

Question 25

Smooth ER

Answer 25

Lacks ribosomal attachment, and appears smooth

Question 26

Rough ER

Answer 26

Contains ribosomes and appears rough

Question 27

Vacuoles

Answer 27

Function to gather food

Question 28

Vesicles

Answer 28

Surrounds proteins; that occur in endocytosis and exocytosis.

Question 29

Ribosomes

Answer 29

Produce protein larger in eucaryotic cells than prokaryotic cells.

Question 30

Mitochondria

Answer 30

Function as the powerhouse

Question 31

Chloroplasts

Answer 31

Function in photosynthesis

Question 32

Golgi complex

Answer 32

Function to package protein; especially important for proteins destined for secretion.

Question 33

Lysosomes

Answer 33

Membraneous sacs that contain digestive enzymes.

Question 34

Nucleus

Answer 34

Contains genetic DNA material

Question 35

Cell morphology (size and shape)

Answer 35

Spears or cocci (singular coccus) spherical shape. Rods or bacilli (singular bacillus) rod shaped. Spirilla or spirochetes (singular spirillum) spiral shaped.

Question 36

Binary fission

Answer 36

Cells divide Each cell divides into two daughter cells

Question 37

Five major chemical or physical conditions, influence growth of bacteria

Answer 37

1) Temperature 2) acidity 3) nutrients 4) oxygen metabolism 5) water

Question 38

Three groups based on temperature

Answer 38

Thermophiles; grow best at 56°C with the range from 45 to 70°C Mesophiles; grows best at body temperature 37°C with the range from 20 to 45°C Psychrophiles; optimal growth refrigerator, temperature 7°C with the range from 1 to 22°C.

Question 39

Acidogenic

Answer 39

Bacteria that produce acids during growth

Question 40

Aciduric

Answer 40

Bacteria that survive and grow in an acidic environment (usually below pH 5.5)

Question 41

Proteases

Answer 41

Enzymes released into the environment that break down proteins into amino acids that can enter the cell.

Question 42

Obligate aerobes

Answer 42

Require oxygen at 20% concentration

Question 43

Microaerophiles

Answer 43

Tolerate low, 4% oxygen concentration

Question 44

Obligate anaerobes

Answer 44

Cannot tolerate oxygen

Question 45

Facultative anaerobes

Answer 45

Can grow with or without oxygen

Question 46

Bactericidal agents

Answer 46

Kill bacteria (chemical, or physical means)

Question 47

Bacteriostatic agents

Answer 47

Prevent growth without killing them

Question 48

Classification of viruses

Answer 48

1) Their type of nucleic acid: DNA or RNA 2) the symmetry of the virus: helical, polyhedral, spherical, complex. 3) whether or not, there is an envelope surrounding itself (envelope or non enveloped).

Question 49

Transmission of viruses

Answer 49

1) droplets (sneezing) 2) direct transfer (touching) 3) contaminated, food, or water 4) insects

Question 50

Fungi include

Answer 50

1) Mushrooms 2) molds 3) yeasts

Question 51

Common protozoa diseases

Answer 51

Malaria