Test #1 New Review

Question 1

Infection

Answer 1

the process by which an “infectious agent” enters a host.

Question 2

Evasion-

Answer 2

Alarm system that doesn’t work :

the “infectious agent” multiplies, spreads, by escaping the host’s immune system.

Question 3

Pathogenicity

Answer 3

studying the ability (or inability) of a germ to cause disease

Question 4

Invasion

Answer 4

the “infectious agent” establishes itself, multiplies, and spreads after infecting the host.

Question 5

Pathology

Answer 5

study of such diseases.

Question 6

Virulence

Answer 6

the degree of pathogenicity/ *how sick you can get/severely sick or life threatening

Question 7

Scientists who supported Spontaneous Generation

Answer 7

Louis Pasteur and Robert Koch

Question 8

Scientists associated with Microscopy

Answer 8

• Antoni van Leeuwenhoek: invented the Simple Microscope which used natural light to produce a magnified image with just one lens.
• Robert Hooke: invented a Compound Microscope which combines lenses to enhance magnification at opposite ends of an Optical Tube that forms the Body of the Microscope

Question 9

Define the Germ Theory of Disease

Answer 9

The pioneering discoveries of Louis Pasteur and Robert Koch led to the “Germ Theory of Disease” that linked germs, which we contract from contaminated air, infected folks, or infested places, to spoilage, decay, decomposition, and human diseases.

Question 10

Etiology

Answer 10

the study of what causes infections and diseases.

Question 11

Koch’s Postulates

Answer 11

1. The pathogen must be present in every occurrence of the Disease and
2. Must be isolated in pure culture and identified by its characteristics
3. When the isolate is intentionally injected into a healthy host
4. It must reproduce symptoms of the disease in the new host
5. Pathogen from new host must match profile of original pathogen.

Question 12

What does each one say about infectious agents?

Answer 12

conclusively linked a particular pathogen to its specific disease symptoms.
Therefore, Microbiology introduces health professionals to Micro-organisms or ‘Microbes’ that are too small for natural eyes, unlike more familiar organisms that we come across in everyday life.

Question 13

Pathogens vs. Non-Pathogens

Answer 13

Pathogens= harmful	
Non-Pathogens= not harmful

Question 14

Disease vs. Opportunistic Pathogens

Answer 14

Disease= particular kind of illness caused by bacteria or an infection.
Opportunistic Pathogens= infect healthy hosts without causing disease in their natural environments. When they infect other body parts, however, they may become pathogenic.

Question 15

Normal Body Flora vs. Transient Flora

Answer 15

Normal Body Flora= permanent

Transient Flora= temporary

Question 16

Nosocomial Infection vs. HAIs

Answer 16

Nosocomial Infections= infections that patients acquire while receiving treatment for other conditions during Hospital stay.
HAIs= this term has been extended to any infection acquired through a Healthcare Facility

Question 17

Estimate Percentage of Nosocomial infections

Answer 17

22% Lower respiratory infections
22% Surgical site infections
17% Gastrointestinal infections
16% Other
13% Urinary tract infections
10% Bloodstream infections
8%: Cutaneous (Skin) Infections

Question 18

Which Normal Flora can be found and where?

Answer 18

• Staphylococcus on the skin, eyes, nose, throat, mouth and urinary tract
• Streptococcus in the nose, throat, and urinary tract
• Diphtheroids on the skin, eyes, nose, throat, and urinary tract

Question 19

What is the effect of Virulent?

Answer 19

Virulence is the degree of pathogenicity. Virulent microbes are pathogenic and capable of causing diseases with life-threatening symptoms.

Question 20

Non-Virulent?

Answer 20

Non-virulent strains have low degree of pathogenicity and may not be non-pathogenic; however, their mild symptoms make them useful as potential vaccines.

Question 21

Avirulent agents?

Answer 21

Avirulent microbes are essentially non-pathogenic

Question 22

Compare Imperial and Metric System Measurements

Size
Temperature
Weight
Volume

Answer 22

IMPERIAL:

• Size: Yards, ft, and inches (yd, ft, in)
• Temperature: Fahrenheit
• Weight: Pounds & Ounces (lbs. & oz)
• Volume: Gallons, Cubic ft, & Cubic inches

METRIC SYSTEM:

• Size: Meter (M)
• Temperature: Celsius
• Weight : Gram (G)
• Volume: Liter (L)

Question 23

Determine the symbols and relationships of these Metric sub-units:
Deci- Micro-
Centi- Nano-
Milli- Pico-

Answer 23

Meter (M) Gram (G)
deci- d- 1/10 dm -
centi- c- 1/100 cm -
milli- m- 1/1000 mm mg
micro- u- 1/million um ug
nano- n- 1/billion nm ng
pico- p- 1/trillion pm pg

All go in increment by (x) 10

Question 24

Compare Simple and Compound Microscopes

Answer 24

“Simple Microscope” was invented by Antoni van Leeuwenhoek and used natural light to produce a magnified image with just one lens.
“Compound Microscope” is built on the original replica of Robert Hooke, and combines lenses to enhance magnification at opposite ends of an Optical Tube that forms the Body of the Microscope.

Question 25

Name Microscope Parts and identify their functions

Answer 25

1. Ocular lenses: the lens at the top that you look through- 10X or 15X power.
2. Tube: Connects the eyepiece to the objective lenses
3. Objective lenses: Basically a housing for a lens. 4X, 10X, 40X, and 100X.
4. Stage: The specimen slides rests on this part of the microscope.
5. Base: supports the microscope
6. Arm: contains the housing for the fine and coarse adjustments and connects the base of the microscope to the nosepiece and ocular.
7. Coarse adjustment knobs: The larger of the two knobs move the stage up or down making things larger or smaller.
8. Fine adjustment knobs: The smaller of two sets of knobs located on either side of the arm. This adjustment is used to make small adjustments in focusing.
9. Light source: Located directly under the stage.
10. Adjustable diaphragm: This rotating wheel on the underside of the stage allows the user to adjust the amount of light that passes through the specimen.

Question 26

Identify the lenses of a Compound Microscope

Answer 26

The Ocular Lens boosts an Objective lens by re-magnifying its image before the viewer sees it. The combined magnification of both lenses is Total Magnification, which multiplies the Magnifying power of any Objective lens by the Ocular lens (usually x10). The Scanning Objective Lens (4x lens) makes the image just a little bigger than the original and is best used for searching. The powerful 100x objective lens produces a final image that looks 1,000 times larger than the real specimen, making the magnified image appear unstable.

Question 27

Name Objective lenses, their magnifying powers, and color codes.

Answer 27

First, the Objective Lens at one end of the optical tube enlarges an image of the specimen using lenses that magnify 4x(Red), 10x(Yellow), 40x(Blue), or 100x(White). Each Objective lens is color-coded for easy identification. An Ocular Lens at the opposite end of the optical tube re-magnifies the enlarged image from the objective lens 10X more.

Question 28

How to calculate Total Magnification

Answer 28

To get the total magnification take the power of the objective (4X, 10X, 40X) and multiply by the power of the eyepiece, usually 10X.

Question 29

Define Resolution

Answer 29

the ability of the lenses to reveal fine DETAILS and structure.

Question 30

Define Useful Magnification-

Answer 30

is any increase in magnification that produces a higher resolution and reveals NEW DETAILS.

Question 31

Define Empty Magnification- Bigger screen TV

Answer 31

increase in magnification that does not improve resolution or reveal any new details.

Question 32

Compare Human Eye Resolution to
4x Objective lens 10x Objective lens
40x Objective lens 100x Objective lens

If a RBC is 5um, which lens would you need to see it?

How much detail whit a 400X objective lens?

Answer 32

The Scanning Objective lens has a total magnification of 40 times (4 x 10). Compared to the human eye, this is sufficient to make an average cell of 5 micrometers (5 mm), which is below the resolution of the Human eye, to appear like it is 200mm. exp. 5*40=200mm

Low-Power objective lens, with Total Magnification of 100 (10 x 10), makes average microscopic bacteria of about 2.0 mm appear like 200mm, which will not be possible with the Scanning Lens. exp. 100*2.0=200

The High Power Lens (40 x 10) yields higher resolution that can make internal cell organelles of 500nm in size look like 200mm; the low-power lens lacks the resolving capacity to make such a structure visible.
Therefore, a more powerful Objective lens (100x10) achieves Useful Magnification compared to the previous one or the Human Eye. The oil immersion objective lens extends useful magnification to 200 nanometers because it has total Magnification of 1,000x.

Limit of human eye resolution is about 200 micrometers.

Question answers: 5*40=200um
200/400=.5 x 1000nm=500nm

Question 33

Generally,

Answer 33

the increase in magnification can improve resolution and reveal new details.