topic 3 - infection and response Flashcards
(36 cards)
What are pathogens?
Pathogens are microorganisms that cause infectious disease, including viruses, bacteria, protists, and fungi. They can infect plants or animals and spread through direct contact, water, or air.
Describe the characteristics of viruses.
Viruses are very small and move into cells, using the host’s biochemistry to make copies of themselves, which leads to the cell bursting and releasing copies into the bloodstream, causing the individual to feel ill.
How do bacteria reproduce and what do they produce?
Bacteria multiply quickly through a process called binary fission and produce toxins that can damage cells.
What is a protist?
Some protists are parasitic, meaning they live on or inside humans and animals, causing damage.
How do fungi reproduce and spread?
Fungi can be single-celled or multicellular with hyphae. They produce spores that spread to other organisms.
List the ways pathogens are spread.
- Direct contact: Examples include kissing and touching contaminated surfaces. 2. By water: Contact with dirty water. 3. By air: Pathogens can be carried in droplets expelled when sneezing, coughing, or talking.
What human behaviors can reduce the spread of disease?
Improving hygiene, reducing contact with infected individuals, and removing vectors are ways to limit the spread of pathogens.
How does vaccination work?
Vaccination involves injecting a small amount of a harmless pathogen to stimulate an immune response, making individuals immune so they cannot be infected or pass the disease on.
What are the symptoms of measles, and how is it spread?
Measles symptoms include fever and red skin rash, and it is spread through droplet infection.
What is HIV and how is it transmitted?
HIV is a virus that attacks the immune system and leads to AIDS. It is transmitted through sexual contact or exchange of bodily fluids.
What methods can reduce the spread of HIV?
Methods include using condoms, not sharing needles, screening blood transfusions, and bottle-feeding infants of HIV-positive mothers.
What are the symptoms and transmission method of Salmonella food poisoning?
Symptoms of Salmonella include fever, stomach cramps, vomiting, and diarrhoea. It is transmitted through ingesting bacteria from raw meat and eggs.
How can bacterial diseases like Gonorrhoea be prevented?
Gonorrhoea can be prevented by using condoms and antibiotics for treatment.
What results do fungal diseases like Rose black spot cause in plants?
Rose black spot causes purple or black spots on leaves, reducing photosynthesis and causing leaves to turn yellow and drop early.
Identify the vector for malaria and its prevention.
The vector for malaria is the female Anopheles mosquito. Prevention methods include using insecticide-treated nets and removing stagnant water.
How does the non-specific defence system protect the body?
The non-specific defence system includes the skin, nose, trachea and bronchi, and stomach, which prevent pathogens from entering the body.
What is phagocytosis?
Phagocytosis is the process where immune cells engulf and consume pathogens, destroying them and preventing illness.
How do vaccines stimulate immunity?
Vaccines replicate the first infection to stimulate white blood cells to produce antibodies before the individual has been infected, resulting in immunity.
What are antibiotics, and how do they differ from painkillers?
Antibiotics kill bacterial pathogens without harming body cells, while painkillers, like aspirin, only treat symptoms, not the cause of disease.
What is the concern regarding antibiotic resistance?
Bacteria are becoming resistant to antibiotics due to mutations and reproduction of resistant strains, leading to ineffective treatments.
Describe the process of developing new drugs.
New drugs are discovered in plants and microorganisms, synthesized by chemists, and tested for safety and efficacy through preclinical and clinical trials.
How are monoclonal antibodies produced?
Monoclonal antibodies are produced by combining lymphocytes that make antibodies with tumor cells that divide rapidly, creating hybridomas that produce identical antibodies
What are some applications of monoclonal antibodies?
They are used in pregnancy tests, laboratories to measure hormones, research, and treatment of diseases by targeting specific antigens
Explain how monoclonal antibodies are used in pregnancy tests.
Pregnancy tests use mobile antibodies that bind to hCG hormone in urine, forming complexes that are captured by stationary antibodies, indicating pregnancy with a blue line.
