B6.3 Flashcards
What is health
A complete state of physical emotional and social wellbeing, and not merley the abscence of disease or infermity
What is disease
The deviation from the normal structure and function of an organism
What is a communicable disease
A disease caused by pathogens that can be transmitted between organisms
What are pathogens
Microorganisms that can cause disease
They most commonly damage cells or release toxins
What are the 4 most common pathogens
Fungi
Bacteria
Viruses
Protozoa
What are antigens
Proteins on the surface of cells and microorganisms
What is a non communicable disease
A disease that cannot be spread between microorganisms such as obesity or cystic fibrosis
What is HIV
Human immunodeficiency virus which causes aids
It attacks T-lymphocytes (by binding to the cells and replicating)
What diseases do AIDS patients catch
People with acquired immune deficiency syndrome have a weakened immune system
This means they can catch diseases such as Tuberculosis from tuberculosis causing bacteria
What does M Tuberculosis do / how does it effect the body
Infection destroys alveolar tissue in the lungs
Causes less oxygen to diffuse into the lungs (due to lower surface area)
Less ATP could be made, so the organism would respire faster
As there is less oxygen in the blood the organism will have breathing problems
How is HIV treated
Using antiviral medicines, to stop the virus replicating
How is HIV spread
Through bodily fluids
Sharing needles
How can HIV spread be reduced
Wear protection such as condoms when having sex
Never sharing needles
Prep is a drug taken prior to exposure, to reduce risk of infection
Pep is taken within 72 hours after exposure to reduce infection
How is staph infection caused
Caused by staph bacteria (staphylococcus)
Symptoms of staph infection
Skin infection
Red lumps on skin (boils)
Red and swollen skin
Sores and blisters
How is staph infection transferred
It can be transferred by contact, but is only dangerous if it enters the body
How can staph be treated
Taking antibiotics such as oxacillin
How is the spread of spah infection reduced
Keeping personal items personal, and constantly cleaning surfaces
What diseases can staph infection cause
If it enters the blood stream it can cause sepsis
What is ringworm
A fungal infection seen on your skin
Causes a scaly / dr / swollen rash
Often appears in silver / red ring shape
How is ringworm treated
Using antifungal creams onto the site
How is the spread of ringworm prevented
Direct and indirect contact
(Sharing items /clothing)
Shower and change clothing once per day
Complications of ringworm
Hair loss
Scarring
Nail deformities
What is influenza
(commonly called the flu)
A common virus that can be spread between people through dropplets
Influenza symptoms
High temperature, headache, bad cold, aching body
How to treat influenza
Annual flu vaccine
Painkillers help to reduce the effects
(People often recover after a week)
Complications of influenza
Can lead to infections such as pneumonia or ear infections
How is the spread of influenza reduced
Covering your mouth and nose when you sneeze / cough
Regularly wash hands
What are the main ways disease is transmitted in animals
.Airborne → droplets and spores
.Direct contact → skin to skin / bodily fluids
.Indirect contact / vehicular contact → surfaces food bedding towels
How do female mosquitos pass on malaria
Only female mosquitos bite humans for blood
In doing this they pass on their saliva which contains anticoagulant properties (so it can take the blood)
In the saliva malaria can also be found
Malaria can be transferred through protists-plasmodium
What is the lytic cycle
A cycle where viruses replicate themselves, destroying a cell
Viruses have receptors so they can bind to specific cells
The virus recognises the pattern of receptors (proteins) on the cell it should infect (these are complimentary to its antigens)
Attaching to the cell allows the virus to insert intergrase into the cell (allowing it to inject its DNA or RNA)
The virus forces the cell to replicate its dna
(The virus DNA is transcribed to RNA so that the cell will transcribe it
A virus is then assembled
The new virus then takes a part of the cell membrane for protection (when leaving the cell)
This causes the cell to be damaged or destroyed
What is a retro virus
A virus with RNA as its genetic material
It uses enzymes to convert RNA to DNA
It the inserts its DNA into the hosts genome to be transcribed
It uses reverse transcriptase
What is reverse transcription
Process of changing RNA to DNA
What is an Incubation period (infection)
Time between being infected and the symptoms being displayed
What is Epidemology
The study of incidence and distributiin if disease
How is disease monitored
Testing for new cases
Death rates
R (reproduction) number
What is an R number
How many cases would each new case cause
How do you test for disease
Looking for symptoms → visual identification
Testing for antigens
PCR test (polymerase chain reaction) → detects genetic material of an organism
How does the skin protect from disease
Its a physical barrier preventing microorganisms from entering the blood
Microbiomes of healthy bacteria compete with pathogens (reduces the number of pathogens)
Glands below your skin secrete sebum which has a low pH (denatures enzymes on the pathogens)
What cells release mucus
Goblet cells
How does mucus and cilia combat against disease
Mucus traps dust and microorganisms preventing them entering your lungs
Cilia (small hairs) move the mucus containing pathogens away from the lungs
The mucus is either swallowed or coughed out
Why is swallowing mucus better than coughing it out
Digestive acid in your stomach has a low pH
This would cause enzymes in pathogens to denature
This would prevent growth
This would also cause certain enzymes controlled reactions like cellular respiration and DNA replication to not function
What are lysozymes
Enzymes that break down peptidoglycan in bacteria cell walls
It can be found in tears and mucus
Why does breaking down peptidoglycan in cell walls kill the cell
It causes the cell to become weaker and more prone to lysis
How do nasal hairs and eyelashes defend against pathogens
Prevents entry of pathogens into the body
What do blood clots do
They provide a barrier preventing pathogens from entering the blood.
How do blood clots / scabs form
When the skin is cut blood begins to leak out
This causes the platelets to become activated (sticky)
Soluble fibrinogen is converted into insoluble fibrin (a protein) by thrombin (an enzyme)
This traps red blood cells forming a clot
The clot eventually hardens forming a scab
What is an anticoagulent
Something that prevents the blood from coming
How do anticoagulant drugs prevent the blood
They bind to the active side of the enzyme (thrombin) that converts fibrinogen to fibrin, as there are no active sides for fibrinogen to bind to
As there is no fibrin a blood clot cannot form
What is a phagocyte
A tyoe of white blood cell that carry out phagocytosis
What happens during phagocytosis
Phagocytes engulf microorganisms and enzymes break down microorganisms
What enzymes can be found in phagocytes
Protease → break down proteins
Carbohydrase → break down carbohydrates
Lypase → break down lipids
Lysozymes → breaks down peptidoglycan
Nuclease → breaks down DNA and RNA
How do bacteria damage cells
Kill cells
Release toxins
What are T-Lymphocytes
White blood cells that:
Recruit phagocytes
Release digestive enzymes to break down microorganisms