Week4 Chapters 3,4,8

Question 1

Locations of Endogenous Microbiota

Answer 1

Skin,
Mouth
Gastrointestinal Tract
Upper Respiratory Tract
Eye

Question 2

Progression of Diseases

Answer 2

• The progression of an infection into a disease depend on certain factors:
1. Virulence factors of microorganisms
2. Quantity of microbial invaders
3. Resistance factors of the host

Question 3

1. Virulence

Answer 3

• Virulence is not a stable characteristic for all pathogens.
• Many microorganisms will undergo mutations that allow them to invade host defenses more effectively.
• Many pathogens produce enzymes to degrade specific substrates of host tissues; others will produce toxins that will damage host tissue.

Question 4

2. Quantity of Microbial Invaders

Answer 4

• Numbers of pathogens or amounts gaining entrance to a host are significant factors as deferminants of disease,
•Quantities of pathogens or their tolins to which an individualis exposed also
Infivence incubation limes of disease,

Question 5

3. Resistance of Host

Answer 5

• General health factors such as age, diet, nutritional factors, stress and environment factors also play a role in the resistance to pathogens.
• Immune responses are often diminished by existing disease or by drug therapy.

Question 6

Causes of Disease

Answer 6

• Diseases have several causes:
1. Microorganisms
2. Malfunctioning of an organ
3. Nutritional deficiency
4. Allergic reaction
5. Abnormal growth of cells

Question 7

Infectious Diseases
2 Types?

Answer 7

• occUr when microorganism in the body multiply and cause damage to the tissues.
• Two types
1. Endogenous
2. Exogenous
Microorganisms that cause infectious diseases are called pathogens.

Question 8

What is Endogenous?

Answer 8

1. Endogenous
   • are caused by microorganisms that are normally present on or in the body without causing harm
   E.g. Periodontal Disease, caries

Question 9

What is Exogenous?

Answer 9

2. Exogenous
   • are caused by microorganisms that are not normally present on or in the body but contaminate the body from the outside.
   E.g. Hepatitis, Common cold, Chicken pox.

Question 10

Endogenous causative agent =

Answer 10

Opportunistic Pathogens

Question 11

Exogenous microorganisms =

Answer 11

Toxigenic Diseases (Poison)

Question 12

Steps of Disease Development

Answer 12

Diseases develop through six basic steps:
1. Source of microorganism
2. Escape of microorganism from the source
3. Spread of microorganism to a new person
4. Entry of microorganism into the person
5. Infection (survival and growth of microorganism)
6. Damage to the body

Question 13

Stages Of An Infectious Disease

Answer 13

Question 14

INCUBATION STAGE

Answer 14

• from initial entrance of infectious agent to display of first symptoms.
• disease agent may be multiplying and producing harmful products.
• may range from a few hours to years

Question 15

PRODROMAL STAGE

Answer 15

• early symptoms
• microoraanisms multiply to numbers to cause “malaise (don’t feel like yourself)
• slight fever, headache, upset stomach

Question 16

ACUTE STAGE

Answer 16

• host displays maximal symptoms of the disease
• very ill

Question 17

CONVALESCENT STAGE

Answer 17

• recovery phase
• number of microorganisms declining or are being destroyed rapidly as body defenses successfully combat disease
• infectious agents are still present and may spread.

Question 18

Stages of disease Development

Answer 18

• Prodromal: the time after incubation and before the characteristic symptoms of infection occur.
• Illness: the stage when the infection causes clinical disease and symptoms.
• Decline: the stage when the infection subsides and the symptoms decrease.
• Convalescence: the stage when the infection is eliminated and the host recovers.

Question 19

Stages of disease development

Answer 19