Week 6 Ch. Disease And Disease Prod. Subst. Flashcards
(26 cards)
7 Categories of Disease
1.Infection: Infectious organisms play a part in at least half of all human illness.
2.Degenerative Disease: disorders that breakdown tissues in the body.
Causes include: hereditary factors, substance abuse, infection or normal “wear and tear” and idiopathic
- Nutritional disorders: includes either a dietary lack of nutrients or an excess of any type.
- Metabolic Disorders: include any disruption of cellular metabolism.
- Immune Disorders: deficiencies in the immune system, caused by either infection or hereditary factors.
- Neoplasms: refers to cancer and other types of
tumors. - Psychiatric disorders: mental disorders
• Often associated with physical disorders
Predisposing cause
A predisposing cause is a factor known to increase the probability that an individual will become ill
• Some causes increase susceptibility to particular diseases.
Risk factors:
1.Age
2.Gender
3.Heredity
4.Living conditions and lifestyles
5. Emotional disturbance
6.Physical and chemical damage
7.Preexisting illness
Idiopathic
Idiopathic: diseases of unknown origin
Latrogenic
latrogenic:
diseases due to adverse treatment effects
Epidemiology
Etiology
Epidemiology
• The study of diseases in entire populations; includes the occurrence, distribution, and transmission of diseases.
includes the tendency to appear in specific demographics
Disease Statistics
•Disease statistics
Incidence rate:
• number of new cases within a population in a specific time frame/population size
• Prevalence rate:
•Number of cases within a population in a specific time frame
• Mortality rate
•Number of cases resulting in death in a specific time frame
Communicable
• Communicable: Can be transmitted from one person to another.
Epidemic
• Epidemic: Many people affected at the same time in a given region. (influenza)
Endemic
• Endemic: Disease found to a lesser extent but continuously. (common cold)
Pandemic
• Pandemic: Prevalent throughout an entire country, continent, or global
Latent Stage
Latent stage:
• no clinical signs are evident
• the incubation period,
• the time between exposure to the microorga and the onset of the signs or symptoms.
Prodromal period
Prodromal period
• Nonspecific, early signs
• the time in the early development of a disease when one is aware of a change in the body, but the signs are nonspecific
• Example: fatigue, loss of appetite, or headache.
Modes of transmission
Modes of transmission
Microorganisms can be transmitted:
1. directly
• by physical contact between individuals
2. indirectly
• through touched objects, dust, or vectors (disease-transmitting organisms).
Bacteria
Bacteria
•Single-celled organisms
•Lack a true nucleus, but do have DNA
•Found everywhere
•Capable of locomotion using flagella
•Pili short flagellae-like structures, assists in gliding ove surfaces & anchors organism to surface as they get nutrie
•Asexual reproduction; reproduce by binary fission independently of other organisms
•Rickettsiae and Chlamydiae can only grow and divide wi living cell, ‘obligate intracellular parasites.’
Bacteria 3 Types
•Types
1. Anaerobic
2. Aerobic
3. Facultative anaerobes
Bacteria Shape
Cocci: round
• In pairs = diplococci (gonorrhea)
• Chains = streptococci
• Clusters = staphylococci
2. Bacilli: straight thin rods
• form endospores
• Tetanus, tuberculosis
3. Curved rods
• Vibrios (slightly curved)
• Spirilla (corkscrew)
• Spirochetes (spirals, but can twist around)
Viruses
• Extremely small microorganisms
• Composed of a core of nucleic acid (RNA or DNA)
surrounded by a coat of proteins
• Grow only within living cells
“obligated intracellular
parasites”
• Do not respond to antibiotics (antibacterial agents)
Infectious Proteins
Prions
Prions
• Composed solely of protein
• Even smaller than viruses
How Creutzfeldt-Jakob disease works
CAUSE
CONSEQUENCES
• Slow incubation & hard
Creutzfeld-Jakod disease is caused by abnormal proteins called prions
and to move property and suffer from
that are not lilled by standard
to destroy
• Produces spongy degeneration of brain tissue
• Creutzfeldt-Jakob disease
NUMAN
PROTEIN
As prions build up in cells, the brain slowly shrinks and the tissue fills with holes until it
in humans (C]D)
Bovine spongiform encephalopathy (BSE) or
Mad cow disease in cows & humans
Fungi
Fungi
• Large group of simple plantlike organisms; few are pathogenic
• Grow best in dark, damp environments
• Reproduces by cell division or by the production of spores
2 types of Fungi
Types
1. Yeasts
• Single-celled forms of fungi
2. Molds
• Fuzzy, filamentous, multicellular forms of fungi
Fungi causes:
• Causes Mycotic infections
• cause very few systemic diseases
• Examples include:
1. (Tinea’ fungal infection
• Cutaneous fungal infection
• Ring shaped rash ‘ringworm’
• Tinea pedis -> ‘athletes foot’
2. Thrush
• some resulting diseases are very dangerous and difficult to cure.
e.g. ‘Pneumonia’ (from inhaled fungal spore)
Protozoa
• Animal-like, single-celled microbes found all over the world
Four Main Types
1. Amebas
• irregular mass of cytoplasm that propels itself by extending part of its cell and then flowing into the extension
2. Ciliates
• covered with tiny hairs called cilia
3. Flagellates
• long whip like filaments called flagella propel these organisms. (Giardia: contaminates water supplies)
4. Apicomplexans/Sporozoa
• cannot propel themselves.
• Unable to grow without a host.
Aseptic Methods
Aseptic Methods:
> Procedures that kill, remove, or prevent the growth of microbes
Sepsis: pathogens in blood
Asepsis: a condition in which no pathogens are present.
1. Sterilization: kills all microorganisms
2. Disinfection: kill most microorganisms
Antisepsis
Antisepsis: process in which pathogens are not necessarily killed but are prevented from multiplying to prevent infection
