Disease Process (MCQ) Flashcards
What are microorganisms ?
They make up the natural microbiome in the human body, skin, mouth, GI tract, respiratory tract and genital tract, as a protective barrier to the body
These are classed an non-pathogenic and don’t cause disease
Classifications of microorganisms
Bacteria
Viruses
Fungi
Protozoa
Describe a virus
Sever types of viruses that can affect the human body E.g the flu or covid19
Described as intracellular viruses, small in size, simpler then cells, cannot survive without a host cell
What is the structure of a virus ?
Genetic material - DNA + RNA
Protein coat (capsid)
Some have an outer envelope
What is bacteria ?
Classified as a single cell organism (unicellular), vary in size, shape and arrangement, they have no nucleus
List the structures of bacteria
Cell wall
Capsule
Plasma membrane
Cytoplasm
Pili
Bacteria flangellum
What does the cell wall of bacteria do ?
Ridgid structure that protects the bacteria, gram negative or gram positive
Can be determined by gram straining
What does the capsule of bacteria do ?
Some bacteria have an external capsule outside the cell wall to protect against the hosts immune system and environmental factors
What does the plasma membrane do for the bacteria ?
This helps to control the movement of nutrients in and out of the cell, important in some cellular processes E.g metabolism for energy
What does the cytoplasm do for the bacteria ?
Contains chromosomes, ribosomes, DNA and RNA, important for exchange
What does the Pili do in bacteria ?
Microscopic hair that helps the bacteria to adhere to host cell and initiates the infection
What does the bacterial flangellum do ?
This helps the bacteria to move and steer towards/away from nutrients or harmful substances, enables mobility
What are the two types of toxins within a bacteria ?
Exotoxins and endotoxins
What are exotoxins ?
Released by bacteria during bacterial growth, damage cell membrane and inhibits protein synthesis
What are endotoxins ?
Contained in the cell wall of gram NEGATIVE bacteria, released on breakdown of the bacteria. They activate the inflammatory process causing fever, can activate the coagulation process
What are the two types of bacteria called ?
Gram POSITIVE and gram NEGATIVE
Describe the buildup of gram Positive bacteria
Inner most plasma membrane
Thick pepridoglycan layer
Outer capsule
Easier to treat with antibiotics
Describe the buildup of gram Negative bacteria
Inner most plasma membrane
Thin peptidoglycan layer
Second plasma membrane
Outer capsule
Harde to treat with antibiotics due to the second membrane later
Colour of gram POSITIVE after staining ?
Purple/violet
Colour of gram NEGATIVE after staining ?
Red/pink
What is pathogenicity ?
The capacity for a microorganism to cause disease
What three mechanisms do microorganisms have to cause disease ?
Direct destruction of cell
Interference with host cell metabolic activity
Exposure to toxins
What factors influence a microorganisms ability to cause disease ?
Virulence - the organisms ability to cause damage to host
Infectivity - the ability for the pathogen to establish an infection in the host. Ability to enter, survive and multiply in host
Host susceptibility - ability of the pathogen to infect or have physical reaction with the body’s immune system after contracting a virus
What are antimicrobials ?
Medications that are used to prevent and treat infections caused by a microorganism
What is an antibacterial ?
The most common type of drugs used to treat bacterial infections in humans
What is antimicrobial resistance ?
The ability of a microorganism to resist the effects of an antimicrobial drug
They have the ability to become resistant
What is an antiviral ?
The drugs used to treat specific viruses
What is the virus life cycle ?
Infection
Replication
Assembly
Release
Name the chain of infection diagram
Organism
Reservoir
Portal of exit
Transmission
Portal of entry
Vulnerable hosts
What is the inflammatory response ?
The body’s first response to injury or infection, triggered by tissue damage
How can our tissues become damaged ?
Infections
Burns
Bites
Injuries causing a break to the skin
Autoimmunity
Allergies
What is acute inflammation ?
This is the bodies way of controlling and localising infection, with the outcome of tissue repair and minimal damage to cells
The three stages of acute inflammation ?
The release of inflammatory mediators
Vascular response
Cellular response
What are the inflammatory mediators ?
Damaged mast cells release Histamine and Prostaglandins
What is the vascular response ?
The inflammatory mediators cause vasodilation and increased vascular permeability in the capillaries round the site of damage
Causing overflow of fluids into the interstitial space
What is the cellular response ?
The inflammatory mediators recruit Leukocytes and Platelets from the blood to the site of damage and eradicate and have clotting effect
Clinical features of acute inflammation
Pain
Redness
Swelling
Heat
What is chronic inflammation ?
This is different form acute because of the duration and type of cells
Lymphocytes and Macrophages are present, these are types of white blood cells
Prolonged accumulation of these can cause tissue damage
What can cause chronic inflammation ?
Persistent infection
Autoimmunity - autoimmune disease
Repeated exposure
What is the most common drug for treating chronic inflammation ?
Corticosteroids
What does NSAIDs stand for ?
Non-steroidal anti-inflammatory drugs
Name some NSAIDS
Ibuprofen and Naproxen
What are some side effects of NSAIDs ?
Gastrointestinal uncles - they reduce the amount of prostoglandins which will in turn increase acid production destroying hr gastric mucosa
Exacerbation of asthma - prostaglandins keep the airway open, these can can block prostaglandins, which leads to the narrowing of the airways
An example of a steroidal anti-inflammatory drug
Corticosteroids
