Body At War Questions Flashcards
Define the word disease?
A disease is a particular abnormal condition that negatively affects the structure or function of all or part of an organism
What is the difference between infectious and non-infectious diseases?
Infectious diseases can spread from one person to another it can be contagious. Non-infectious diseases cannot spread or transfer from one person to another
Name 3 infectious and 3 non-infectious diseases?
Infectious- Influenza, Chicken Pox, Measles, COVID-19, Mumps, Athlete’s foot
Non-Infectious- Asthma, Cancer, Epilepsy
Describe 3 ways disease causing microbes can spread
Air, water, food, direct contact, indirect contact, coughing, sneezing
What is a host?
Organism that carries the pathogen and can spread to infect others.
What is a vector? Give an example
An organism that can spread disease but is not harmed itself. E.g. mosquitoes carrying the
pathogen that causes malaria and will spread when they bite.
What is the name given to a disease causing microbes?
Pathogen
Bacteria
Virus
Fungi
Why are viruses not classified as living?
Viruses require a host cell to replicate. Without a living host cell, the virus is unable to replicate.
What is and antibiotic? Give an example.
Examples include penicillin. These are chemicals that break down the bacterial cell in the body
and destroys bacteria.
How do bacteria reproduce?
Through binary fission
What conditions do Bacteria like to reproduce?
Warm and wet/damp
Name 2 diseases caused by bacteria
Salmonella (food poisoning), chlamydia, whooping cough, tuberculosis.
What is antibiotic resistance?
When antibiotics have no effect in the body as the bacteria have developed a resistance to them.
How do resistant bacteria (super bugs) develop?
Overuse or misuse of antibiotics. strains of bacteria that have adapted after coming into contact
with an antibiotic. Once this happens, these bacteria become “resistant” to the antibiotic to which they have been exposed, which means the antibiotic cannot kill the bacteria or stop them from multiplying.
Describe a virus.
Avirusis a tiny, infectious particle that can reproduce only inside a host cell.
Name 2 diseases caused by viruses.
Chicken pox, common cold, hepatitis, AIDS
How do viruses reproduce?
The virus uses/hijacks the host cell to replicate. The DNA is injected into the host and the host makes copies of the viral DNA. Also, viruses can mutate and change the shape of their antigens.
Describe a fungus.
Any of a group of spore-producing organisms feeding on organic matter, including moulds, yeast,
mushrooms, and toadstools.
Name 2 fungal diseases.
Thrush, athletes foot, ringworm.
How do fungi reproduce?
Fungi reproduce asexually by fragmentation, budding, or by producing spores.
What is the difference between an antiseptic and disinfectant?
Both Kill microorganisms. An antiseptic is applied to the body, while disinfectants are applied to
nonliving surfaces, such as countertops and handrails.
How can bacterial infection spread?
Binary fission- in the correct conditions they will divide asexually every 20 minutes
Name 4 parts of the first line of defense
hair, cilia, mucous, intact skin, stomach acid, tears
Name 2 physical and 2 chemical barriers to disease (first line of defence).
Physical include: hair, cilia, mucous, intact skin
Chemical: stomach acid, lysosomes in tears, sweat.
What is a phagocyte?
A type of white blood cell which engulfs pathogens.
Why does swelling and redness often occur after infection?
Certain immune cells release HISTAMINE, a chemical that causes an INCREASE of blood flow
to the area where pathogens have been detected.
White blood cells then come in and consume pathogens (Phagocytosis). This leads to the site becoming Red, swollen, hot and painful. Known as inflammation.
Why is it good for scabs to form over cuts?
To seal the skin barrier and prevent further infection
What are antigens?
Antigens are proteins located on the surface of our cells and other pathogens. They help the
body to determine what is self and non self.
What cells produce antibodies?
Lymphocytes- B cells produce antibodies.
Draw a labelled diagram of an antigen-antibody complex and explain how it works?
Neutralisation works by antibodies binding to the pathogen to stop the pathogen from replicating
or invading other cells. This makes it easier for phagocytes to engulf the pathogen. Clumping works by antibodies binding to several pathogens. This groups many pathogens together. Phagocytes then come and engulf the clumped pathogens.
In both methods, the antibody binds to the antigen on the pathogen. The antibody must have the
same complementary shape as the pathogen.
Where are B and T lymphocytes (white blood cells) produced?
B cells – bone marrow
T cells – thymus
What are memory white blood cells and what are their function in immunity?
After B cells produce antibodies, some B cells are stored are memory cells. This is stored in
the body for a quicker and larger response if the body is encountered with the same pathogen
later.
What is the difference between active and passive immunity?
Active – the body’s natural defence against the pathogen. Eg. Producing antibodies.
Passive – the body is induced eg. Antiviral , vaccinations
What are vaccines and how do they work?
Vaccines contain a weakened form of the pathogen. This introduces the body to the pathogen so then the body can build immunity. The body can make B cells and T cells specific to the
introduced pathogen to then make memory cells so when the body encounters the pathogen, the body is able to respond faster.
Why is it necessary to often have 2 injections against a specific disease?
Some diseases require a booster injection. This is because the memory cells may do not live
for long and more need to be produced.
What hygiene conditions would help decrease the spread of disease?
Wash hands regularly, cover nose and mouth when coughing, use gloves when handling food.
What is an STI/STD?
Sexually Transmitted Infection/Disease
Name 2 ways these diseases/infections can spread
Sexual intercourse (Vaginal or oral)
Passed from mother to baby in Childbirth or pregnancy
