B3 Flashcards
What are viruses?
Viruses are tiny infectious agents that are not cells.
How do viruses reproduce?
Viruses reproduce rapidly inside body cells by making copies of themselves.
What happens to cells infected by viruses?
The infected cells usually burst, releasing new viruses.
What causes illness when infected by a virus?
Cell damage caused by the bursting of infected cells makes you feel ill.
What is rose black spot?
Rose black spot is a fungal disease that causes purple or black spots on the leaves of rose plants.
What symptoms does rose black spot cause?
The leaves turn yellow and may not photosynthesize properly, affecting plant growth.
How is rose black spot spread?
It is spread in water or by the wind.
How can gardeners treat rose black spot?
They can use chemicals that kill fungi or strip the affected leaves.
What is measles?
Measles is a viral disease spread by droplets from an infected person’s sneeze or cough.
What are the symptoms of measles?
Symptoms include a red skin rash and fever.
Why are most people vaccinated against measles?
To prevent serious complications that can lead to death.
How is HIV spread?
HIV is spread by sexual contact or exchanging bodily fluids.
What initial symptoms does HIV cause?
HIV causes flu-like symptoms for a few weeks.
What can control HIV infection?
Antiretroviral drugs can control HIV by stopping the virus from copying itself.
What happens if HIV is not controlled?
The virus attacks immune cells, leading to late stage HIV infection or AIDS.
What is tobacco mosaic virus (TMV)?
TMV is a virus affecting many plant species, causing discolored leaves with a mosaic pattern.
What effect does TMV have on photosynthesis?
Discolored leaves have less chlorophyll, resulting in reduced photosynthesis.
What causes malaria?
Malaria is caused by a protist transmitted by mosquitoes.
How do mosquitoes transmit malaria?
Mosquitoes become infected when they feed on an infected person.
What are some symptoms of malaria?
Symptoms include fever, chills, and flu-like illness.
True or False: The spread of malaria can be controlled.
True.
Fill in the blank: HIV can be controlled with _______.
antiretroviral drugs.
What does the spread of HIV through sharing needles indicate?
It indicates a risk of transmission among drug users.
Give one way that measles can be spread.
By droplets from an infected person’s sneeze or cough.
What is Rose Black Spot?
A fungal disease causing purple or black spots on the leaves of rose plants
It can lead to yellowing and dropping of leaves, reducing photosynthesis.
How does Rose Black Spot affect plant growth?
Less photosynthesis occurs, so the plant doesn’t grow very well
The dropping of leaves impacts the plant’s ability to produce energy.
How is Rose Black Spot spread?
In water or by the wind
This allows the fungus to infect other plants easily.
What is one chemical that gardeners can use to treat Rose Black Spot?
Fungicides
These chemicals are specifically designed to kill fungi.
What should gardeners do with affected leaves of rose plants?
Strip them off and destroy them
This prevents the fungus from spreading to other rose plants.
What type of pathogen causes malaria?
Protist
Malaria is specifically caused by a single-celled organism.
Where does part of the protist’s life cycle take place in the context of malaria?
Inside the mosquito
The mosquito acts as a vector for the disease.
What role do mosquitoes play in the transmission of malaria?
They are vectors that help spread malaria
Mosquitoes pick up the protist from infected animals and transmit it to others.
What happens when mosquitoes bite infected animals?
They pass on the protist to other animals, including humans
Humans can contract malaria from these bites.
What are the symptoms of malaria?
Repeating episodes of fever
Malaria can lead to severe health complications and even death.
What is one way to reduce the spread of malaria?
Stopping mosquitoes from breeding
This can significantly lower the incidence of malaria.
How can people protect themselves from mosquito bites?
Using mosquito nets
This is an effective preventive measure against malaria.
What feature of the human body helps trap particles that could contain pathogens?
Nose hairs
Nose hairs are a part of the body’s defense system against pathogens.
What structures line the trachea and bronchi to help protect against pathogens?
Cilia
Cilia move mucus up to the back of the throat where it can be swallowed.
What does the stomach produce to help kill pathogens?
Hydrochloric acid
Hydrochloric acid helps to destroy pathogens ingested with food.
What is the process called when white blood cells engulf and digest pathogens?
Phagocytosis
Phagocytosis is a key method used by white blood cells to eliminate pathogens.
What do white blood cells produce in response to foreign antigens?
Antibodies
Antibodies are specific to the antigens of invading pathogens.
What is the role of antibodies in the immune response?
Lock onto invading pathogens
Antibodies ensure pathogens can be found and destroyed by other white blood cells.
How do vaccinations help protect against diseases?
They involve injecting small amounts of weakened pathogens
This process helps the immune system recognize and fight future infections.
What happens when a person is infected with the same pathogen after vaccination?
White blood cells rapidly make antibodies
This rapid response means the person is naturally immune to that pathogen.
What do antitoxins produced by white blood cells do?
Stop toxins produced by invading bacteria from working
Antitoxins are part of the immune system’s defense against bacterial infections.
True or False: Vaccines have helped eliminate diseases that used to be common.
True
Vaccination programs have significantly reduced the incidence of many infectious diseases.
Fill in the blank: The most important part of your immune system is the _______.
white blood cells
White blood cells play a crucial role in fighting infections.
What do vaccinations help prevent?
Vaccinations help prevent diseases before they occur.
Vaccination is a proactive measure rather than just treatment.
What do vaccinations involve?
Vaccinations involve injecting small amounts of dead or inactive pathogens into the body.
These pathogens contain antigens that trigger an immune response.
What do the antigens on the surface of pathogens do?
Antigens cause white blood cells to produce antibodies to attack the pathogens.
This immune response is crucial for future protection.
What happens if you are infected with the same pathogen after vaccination?
Your white blood cells quickly produce a lot of antibodies.
This rapid response helps to eliminate the pathogen.
How do antibodies help after vaccination?
Antibodies can kill the pathogen, making you less likely to get ill.
This is a key benefit of vaccination.
What is an example of a disease that children are vaccinated against?
Children are vaccinated to protect against measles.
Measles vaccination is an important public health measure.
What is an epidemic?
A big outbreak of a disease is called an epidemic.
Epidemics can be controlled through vaccination.
How can epidemics be prevented?
Epidemics can be prevented if lots of people are vaccinated.
This creates herd immunity, reducing disease transmission.
What is one pro of vaccination?
Vaccines have helped control many communicable diseases, such as polio.
This has significantly improved public health.
What is one con of vaccination?
Vaccines don’t always work and may not provide immunity.
This can vary based on individual health and the vaccine type.
What is a possible adverse reaction to a vaccine?
A bad reaction can include swelling or fever.
These reactions are usually mild and temporary.
Fill in the blank: Antigens are the molecules on the surface of pathogens, and _______ are produced by white blood cells to fight pathogens.
antibodies
True or False: Vaccination guarantees complete immunity from diseases.
False
Vaccination increases immunity but does not guarantee it.
In the example given, why did Basia not get ill from the flu virus while Cassian did?
Basia was vaccinated against flu, providing her with immunity, while Cassian was not vaccinated.
This illustrates the effectiveness of vaccines in preventing illness.
What do some drugs do regarding disease symptoms?
Some drugs help to get rid of the symptoms of a disease, e.g. painkillers reduce pain.
What is the role of antibiotics?
Antibiotics (e.g. penicillin) kill bacteria.
What impact did antibiotics have on communicable diseases?
The use of antibiotics greatly reduced the number of deaths from communicable diseases caused by bacteria.
Do antibiotics destroy viruses?
No, antibiotics don’t destroy viruses (e.g. flu viruses).
How do viruses reproduce?
Viruses reproduce using your own body cells.
What can happen to bacteria in relation to antibiotics?
Bacteria can mutate and some mutations cause them to become resistant to antibiotics.
What is MRSA?
MRSA is a resistant strain of bacteria that has increased as a result of natural selection.
Where do many drugs initially come from?
Many drugs first came from plants.
What do plants produce to defend themselves?
Plants produce chemicals to defend themselves against pests and pathogens.
What is aspirin used for and where does it come from?
Aspirin is used as a painkiller and was made from a chemical found in willow.
What is digitalis used for and where does it come from?
Digitalis is used to treat heart conditions and was made from a chemical found in foxgloves.
Who discovered penicillin and from what?
Alexander Fleming discovered penicillin from a type of mould called Penicillium.
What is the pharmaceutical industry responsible for?
The pharmaceutical industry makes and sells drugs.
What is the first step in drug testing?
Once a possible drug has been identified, it undergoes preclinical testing.
What are the key components of preclinical testing?
- Efficacy (whether it works)
- Toxicity (how harmful it is)
- Dosage (the correct amount)
What happens if a drug passes preclinical testing?
It moves on to clinical testing.
What is the purpose of clinical trials?
To test the drug on humans to ensure its safety and efficacy.
In clinical trials, what is monitored?
- Side effects
- Optimal dosage
What is the significance of group assignments in clinical trials?
Participants are often divided into groups to compare effects.
What is the outcome of clinical trials?
The results determine whether the drug can be approved for public use.
What are the two main stages in the development of new drugs?
Preclinical testing and clinical testing
These stages ensure that drugs are safe and effective before being given to humans.
What is the purpose of preclinical testing?
To test drugs on human cells, tissues, and live animals
This helps determine efficacy, toxicity, and optimal dosage.
What three aspects are assessed during preclinical testing?
- Efficacy
- Toxicity
- Dosage
What happens in the clinical testing stage after a drug passes animal tests?
It’s tested on human volunteers in a clinical trial
This phase evaluates the drug’s safety and effectiveness in humans.
Why are healthy volunteers used at the start of clinical trials?
To ensure the drug doesn’t have harmful side effects in a normally functioning body
During clinical trials, how is the initial drug dosage administered?
A very low dose is given and increased gradually
This helps monitor side effects and efficacy.
What is the optimum dose of a drug?
The dose that is most effective with few side effects
How are patients grouped in clinical trials to test a new drug?
Group 1 receives the new drug, Group 2 receives a placebo
What is the purpose of a placebo in clinical trials?
To compare the effects of the new drug against a substance that doesn’t have any effect
What is meant by ‘blind’ clinical trials?
Patients do not know if they are receiving the drug or placebo
What does ‘double-blind’ mean in the context of clinical trials?
Neither the patient nor the doctor knows who has taken the drug or placebo
What must happen to the results of clinical trials before publication?
They must undergo peer review
This process helps to validate the findings and prevent false claims.
What is the first step in drug testing?
Testing on human cells and tissues in the lab
What is toxicity in the context of drug testing?
How harmful the drug is and whether it has side effects
Fill in the blank: Clinical trials are often ______, meaning neither the patient nor the doctor knows who is receiving the treatment.
double-blind
