B5-Communicable Diseases Flashcards
(114 cards)
1
Q
What is agar gel?
A
Widely used solid (gel) culture medium used for growing microorganisms
2
Q
What is binary fission?
A
Reproduction by simple cell division, for example in bacteria
3
Q
What is chlorosis?
A
The yellowing seen on the leaves of plants when they cannot make chlorophyll due to a lack of magnesium ions
4
Q
What is a communicable disease?
A
Diseases caused by pathogens that can be passed from one organism to the other
5
Q
What is culture medium?
A
a liquid or gel used to support the growth of microorganisms or other cultures, often containing specific nutrients
6
Q
What is inoculation?
A
Introducing microorganisms to a culture medium, or introducing modified microorganisms into an individual to protect them against disease
7
Q
What are microorganisms?
A
organisms that are usually single-celled and can only be seen using a microscope. They include bacteria, fungi, viruses and protists
8
Q
What is mutation?
A
Mutation is a change in the genetic material of an organism
9
Q
What are non-communicable diseases?
A
Diseases that are not infectious and cannot be passed from one organism to another
10
Q
What are pathogens?
A
Microorganisms that cause disease
11
Q
What are Sexually Transmitted Diseases (STD’s)?
A
Diseases transmitted from an infected person to an uninfected person by unprotected sexual contact
12
Q
What is a vaccine?
A
Dead or inactive pathogenic material used in vaccination to develop immunity to a disease in a healthy person
13
Q
What is a virus?
A
Pathogens that are much smaller then bacteria and can only reproduce inside living cells of other organisms
14
Q
What is a Toxin?
A
A harmful chemical produced by a microorganism
15
Q
What is a protist?
A
Protists are single-celled eukaryotic organisms
16
Q
What factors can effect health?
A
Diet, Stress, Life Situations
17
Q
How does diet effect health?
A
If you do not get enough to eat, or the right nutrients, you may suffer from diseases ranging from starvation to anaemia or rickets. Too much to eat, or the wrong type of food, can lead to problems such as obesity, some cancers, or type 2 diabetes
18
Q
How does stress effect health?
A
A certain level of stress is inevitable in everyone’s life and is probably needed for our bodies to function properly. However, scientists are increasingly linking too much stress to an increases risk of developing a wide range of health problems. These include heart disease, certain cancers, and mental health problems
19
Q
How do Life Situations effect health?
A
Life situations include: the part of the world where you live, your gender, your financial status, your ethnic group, the levels of free healthcare where you live, how many children you have, and local sewage and rubbish disposal. People often have little or no control over their life situations, especially children or young people. Yet such factors have a big effect on health and well-being. These include communicable and non-communicable diseases
20
Q
How does a bacteria make somebody ill?
A
bacteria divide rapidly by binary fission. They may produce toxins that which can damage tissue and make you sick.
21
Q
How does a virus make somebody ill?
A
Viruses invade host cells and use them to make new virus particles. Once the new viruses are made they cause the host cell to burst. The cell damage makes us feel ill
22
Q
How are pathogens spread?
A
By air, by direct contact, by water
23
Q
How are pathogens spread by air?
A
Many pathogens including bacteria, viruses and fungal spores are carried and spread from one organism to another in the air. In human diseases, droplet infection is common. When you are ill, you expel tiny droplets full of pathogens from your breathing system when you cough, sneeze or talk. Other people breath in the droplets, along with the pathogens they contain, so they pick up the infection.
24
Q
How are pathogens spread by direct contact?
A
Some diseases are spread by direct contact of an infected organism with a healthy one. This is common in plant diseases, where a tiny piece of infected plant material left in a field can infect an entire new crop. In people, diseases including STI’s such as syphilis and chlamydia are spread by direct contact of the skin. Pathogens such as HIV/AIDS or hepatitis enter the body through sexual contact, cuts, scratches and needle punctures that give access to the blood. Animals can act as vectors of both plant and animal diseases by carrying a pathogen between infected and uninfected individuals
25
How are pathogens spread by water?
Fungal spores carried in splashes of water often spread plant diseases. For humans, eating raw, undercooked or contaminated food, or drinking water containing sewage can spread diseases such as diarrhoeal diseases, cholera or salmonellosis. The pathogen enters your body through your digestive system
26
What are the types of pathogens?
Viruses, Bacteria, Fungi, Protists
27
How do bacteria reproduce?
by binary fission, they divide rapidly by simple cell division
28
What is required to grow a microorganism in a lab?
To grow a microorganism in a lab, you must provide them with everything that they need. To do this they are provided with a culture medium. This contains carbohydrate as an energy source, various minerals, a nitrogen source so that they can make proteins, and sometimes other chemicals. Most microorganisms also need warm and also oxygen to grow
29
Why do schools not inoculate microorganisms above 25*C?
If you culture bacteria at 37*C (human body temperature) there would be a high risk of growing dangerous pathogens. It also makes the microorganisms grow at a much faster rate
30
What is a common culture medium?
Agar gel
31
What is the bacteria division time?
The amount of time it takes for the bacteria to reproduce
32
How do you prevent bacterial growth?
You can raise or lower the temperature to a temperature where the bacteria cannot survive. Chemicals can also be used to stop them growing or kill them. Disinfectants are chemicals used to kill bacteria in the environment around us. Antiseptics are disinfectants that are safe to use on human skin. Antibiotics are chemicals that are safe to use inside the human body
33
What is the work of Louis Pasteur?
Louis Pasteur showed that microorganisms caused disease. He developed vaccines against diseases such as anthrax and rabies
34
What is the work of Joseph Lister?
Joseph Lister started to use antiseptic chemicals to destroy pathogens before they caused infection in operating theatres
35
What is the work of Ignaz Semmelweis?
Semmelweis was a doctor in the mid-1850’s. At this time many women died frim childbed fever a few days after giving birth. However, no one knew what caused it. Semmelweis noticed that his students went straight from dissecting a dead body to delivering a baby without washing their hands. He noticed that another doctor died of identical symptoms after cutting himself whilst working on a body. Semmelweis wondered is they where carrying a cause of disease from the corpses to their patients. He therefore insisted that his students wash their hands before delivering babies. Immediately, fewer mothers died from the fever. However, other doctors were very resistant to Semmelweis’s ideas
36
How do you prevent the spread of communicable diseases?
Hygiene, Isolating infected individuals, Destroying or controlling vectors, and Vaccination
37
How does hygiene prevent the spread of communicable diseases?
Simple hygiene measures are one of the most effective ways of preventing the spread of pathogens. These include:Hand washing, especially after using the toilet, before cooking, or after contact with an animal or someone who has an infectious illness.Using disinfectant on kitchen work surfaces, toilets, etc. To reduce the number of pathogensKeeping raw meat away from food that is eaten uncooked to prevent the spread of pathogensCoughing or sneezing into a handkerchief, tissue, or your hands (and then washing your hands)*Maintaining the hygiene of people and agricultural machinery to help prevent the spread of plant diseases
38
How does isolating infected individuals prevent the spread of communicable diseases?
If someone has an infectious disease, especially a serious disease such as Ebola or cholera, they need to be kept in isolation. The fewer healthy people who come into contact with the infected person, the less likely it is that the pathogens will be passed on. This is also true of plants infected with diseases but it is only possible with smaller plants that can be moved and destroyed easily.
39
How does Destroying or controlling vectors prevent the spread of communicable diseases?
Some communicable diseases are passed on by vectors. For example, mosquitoes carry a range of diseases, such as malaria and dengue fever. Houseflies can carry over 100 human diseases, while rats also act as vectors of disease. Aphids transmit over 150 different plant diseases and different types of beetle carry disease to plants in the form of viral, bacterial, and fungal pathogens. If the vectors are destroyed, the spread of the disease can be prevented. By controlling the number of vectors, the spread of disease can be greatly reduced
40
How does vaccination prevent the spread of communicable diseases?
During vaccination doctors introduce a small amount of a harmless form of a specific pathogen into your body. As a result, if you come into contact with the live pathogen, you will not become ill as your immune system will be prepared. Vaccination is a very successful way of protecting large numbers of humans and animals against serious diseases. However, it cannot protect plants against disease as they do not have an immune system
41
What convinced many people pathogens where real?
Once microscopes improved, it became possible to see the pathogens more clearly.
42
What is measles?
The main symptoms of Measles are a fever and a red skin rash. The virus is spread by the inhalation of droplets from coughs and sneezes and is very infectious. Measles is a serious disease that can cause blindness and brain damage and may be fatal if complications arise. There is no treatment for measles, so if someone becomes infected with they need to be isolated to stop the spread of the virus. Measles is now rare in the UK as a result of improved living conditions and a vaccination programme for young children.
43
What is HIV/AIDS?
Many people do not realise they are infected with HIV, this is because the virus only causes a mild, flu-like illness to begin with. HIV attacks the immune cells and after the initial mild illness it remains hidden inside the immune system, sometimes for years, until the immune system is so badly damaged that it can no longer deal with infections or certain cancers. At this point the patient has developed AIDS. HIV is spread through direct sexual contact and the exchange of body fluids such as blood. There is no cure for HIV/AIDS and no vaccine against it. The spread of the disease can be prevented by using condoms, not sharing needles, screening blood used for transfusions, and HIV-positive mothers bottle-feeding their children. The regular use of antiretroviral drugs can prevent the development of AIDS for many years and give HIV positive patients an almost normal life expectancy
44
What is Tobacco Mosaic Virus?
Tobacco Mosaic Virus (TMV) was the first virus to ever be isolated. It is a widespread plant pathogen that affects around 150 species of plants including tomatoes and tobacco plants. It causes a distinctive “Mosaic” pattern of discoloration on the leaves as the virus destroys the cells. This affects the growth of the plant as the affected areas of the leaf cannot photosynthesise. TMV can seriously reduce the yield of a crop. It is spread by contact between diseased plant material and healthy plants, and insects can act as vectors. The virus can remain infectious in the soil for about 50 years. There is no treatment for and farmers now grow TMV-resistant strains of many crop plants. Good hygiene and good pest control can prevent the spread of TMV
45
What are 3 Viral Diseases?
Measles, HIV/AIDS, and Tobacco Mosaic Virus
46
What are 3 Bacterial Diseases?
Salmonella, Gonorrhoea, and Agrobacterium Tumefaciens
47
What is Salmonella?
Salmonella are bacteria that live in the guts of many different animals. They can be found in raw meat, poultry, eggs, and egg products such as mayonnaise. If these bacteria get into our bodies, they disrupt the balance of the natural gut and cause Salmonella food poisoning. A common cause of this is eating undercooked food, where the bacteria have not been killed by heating. The symptoms develop within 8-72 hours after eating infected food. Fever, abdominal cramps, vomiting, and diarrhoea are caused by the bacteria and the toxins they secrete. In very young and old people it can be fatal, usually due to dehydration. In the UK, poultry are vaccinated against Salmonella to prevent the spread of the disease.
48
What is Gonorrhoea?
Gonorrhoea is an STD. It is spread through by unprotected sexual contact with an infected person. Like many STD’s gonorrhoea has symptoms in the early stages, but then becomes relatively symptomless. The early symptoms include a thick yellow or green discharge from the vagina or penis and pain on urination. However, 10% of infected men and 50% of infected women get no symptoms at all. Untreated gonorrhoea can cause long-term pelvic pain, infertility, and ectopic pregnancies. Babies born to infected mothers may have severe eye infections and even become blind. As Gonorrhoea is bacterial it can be treated with antibiotics. It can also be prevented by the use of a condom.
It is caused by a bacterium and was easily treated with the antibiotic penicillin until many resistant strains appeared.
49
What is Agrobacterium Tumefaciens?
Agrobacterium Tumefaciens is a bacterium that causes crown galls - a mass of unspecialised cells that often grow at the join between root and shoot in infected plants. The bacteria insert plasmids into the plants cells and cause a mass of new undifferentiated genetically modified cells to grow. Scientists make use of the way bacteria naturally infect plants and give them new added genes. They manipulate the bacteria so that they carry desirable genes into the cells they infect.
50
What are 2 fungal diseases?
Athlete’s foot, Rose Black Spot
51
What is a disease caused by protists?
Malaria
52
What is Rose Black Spot?
Rose Black Spot is a fungal disease of rose leaves. It causes purple or black spots to develop on leaves and it is a nuisance in gardens and for commercial flower growers. The leaves often turn yellow and drop early. This weakens the plant because it reduces the area available for photosynthesis. As a result the plant does not flower well - and the main reason people grow roses is for flowers. The spores of the fungus are spread in the environment, carried by the wind. They are then spread over the plant after it rains in drips of water that splash from one leaf to plant to another. The spores stay dormant over winter on dead leaves and on the stems of rose plants. Gardeners try to prevent the spread by removing and burning affected leaves and stems. Chemical fungicides can also help to treat the disease and prevent it spreading. Horticulturists have bred types of roses that are relatively resistant to black spot but the disease still cannot be prevented or cured.
53
What is Malaria?
Malaria is a disease that is caused by protist pathogens that are parasites - they live and feed on other living organisms. The life cycle of protists includes time in the human body and time in the body of a female anopheles mosquito. The protists reproduce sexually in the mosquito and asexually in the human body. The mosquitoes act as vectors of the disease. The female mosquito needs 2 meals of human blood before she can lay her eggs, and this is when the protists are passed into the human bloodstream. The protists travel around the human body in the circulatory system. They affect the liver and damage red blood cells. Malaria causes recurrent episodes of fever and shaking when the protists burst out of the blood cells, and it can be fatal. If malaria is diagnosed quickly it can be treated by using a combination of drugs.
54
How does skin act as a defence against microorganisms entering your body?
Your skin cover your body and acts as a barrier. It prevents bacteria and viruses reaching tissues beneath. If you damage or cut your skin, the barrier is broken but your body restores it. You bleed, and the platelets in your blood set up a chain of events to form a seal over the cut, stopping the pathogens getting in. It also stops you bleeding to death
Your skin produces antimicrobial secretions to destroy pathogenic bacteria.
Healthy skin is covered with microorganisms that help keep you healthy and act as an extra barrier to the entry of pathogens
55
What are the defences of the respiratory system?
Your nose is full of hairs and produces a sticky liquid, called mucus. The hairs and mucus trap particles in the air that may contain pathogens or irritate your lungs. If you spend time in an environment with a lot of air pollution, the mucus you produce when you blow your nose is blackened, showing that the system works.
The trachea and bronchi also secrete mucus that traps pathogens from the air. The lining of the tubes is covered in cilia - tiny hair like projections from the cells. The cilia beat to waft the mucus up to the back of the throat where it is swallowed
56
What are the defences of the digestive system?
The stomach produces hydrochloric acid and this destroys the microorganisms in the mucus you swallow, as well as the majority of pathogens that you take in through your mouth in your food and drink.
57
How do white blood cells in your immune system help protect you body?
They ingest microorganisms, They produce antibodies, and They produce antitoxins
58
How does producing antibodies help protect against disease?
Lymphocytes produce special chemicals called antibodies. These target specific bacteria and viruses and destroy them by attacking the antigens on them and binding to them. You need a unique antibody for each type of pathogen as they will have a different antigen. When your lymphocytes have produced antibodies against a particular pathogen once, they can be made very quickly if that pathogen gets into the body again. This stops you getting the disease twice.
59
How does producing antitoxins help protect against disease?
Lymphocytes produce antitoxins that bind to a toxin and neutralise the toxins being given out by the bacteria, preventing them from causing any harm
60
How does pahgocytes ingesting microorganisms help protect against disease?
Phagocytes ingest pathogens, digesting and destroying them. This prevents the pathogen causing any harm to cells / tissue and it also prevents the pathogens reproducing. This process is called phagocytosis
61
What type of white blood cell produces antitoxins?
Lymphocytes
62
What type of white blood cell performs Phagocytosis?
Phagocyte
63
64
What are aphids
Aphids are a group of insect plant pests. They have sharp mouthparts that penetrate into the phloem vessels of the plants so that they can feed on the sugar-rich phloem sap. Aphids attack in huge numbers, depriving the plant cells of the products of photosynthesis. This can seriously damage and weaken the plant. Aphids also act as vectors, transferring viruses, bacteria and fungi from diseased plants into the tissue of healthy plants.
65
How are Aphids destroyed?
Aphids can be destroyed using chemical pesticides or, in enclosed spaces such as greenhouses, using biological pest control. Releasing aphid-eating insects such as ladybirds and their larvae can control the pathogen population so it does not have an impact on the success of the crop
66
What are non-communicable diseases in plants?
Mineral ion Deficiencies
67
What is a magnesium ion deficiency?
Plants take magnesium ions from the soil to make the chlorophyll needed for photosynthesis. If the level of magnesium ions in the soil is low, the plant cannot make enough chlorophyll. The leaves become yellow and growth slows down as the plant cannot photosynthesise fully. The yellowing of the leaves due to a lack of magnesium ions is known as chlorosis
68
What is nitrate deficiency?
Plants need a good supply of nitrate ions from the soil to convert sugars made in photosynthesis into proteins needed for growth in protein synthesis. If there is a nitrate deficiency in the soil, protein growth will be limited, the growth of plants will be stunted, and they will not produce a crop properly.
69
What are symptoms of a diseased plant?
Stunted growth,
Spots on leaves,
Areas of decay or rotting,
Growths,
Malformed stems and leaves,
Discoloration,
Presence of visible pests
70
What are physical barriers against pathogens as plant defences?
Plants have a number of physical defences that reduce the invasion of pathogens:
The cellulose cell wall that strengthens plant cells also helps to resist invasion by microorganisms. This is one reason why the actions of aphids are so damaging, it breaches the barrier and gives pathogens a way into the cells.
The tough waxy cuticle on the surface of leaves acts as a barrier to the entry of pathogens. It is only at the stomata that pathogens actually have access to the cells within the leaf
Bark on trees, and a layer of dead cells on the outside of stems, form a protective layer that is hard for pathogens to penetrate. When the dead cells are lost or shed, the pathogen will fall off with them.
Leaf fall - deciduous trees lose their leaves every autumn. Any pathogens that infect the leaves, such as rose black spot, fall off the tree when the leaves are lost
71
What is fungi made out of?
Hyphae
72
Required practical:The effect of antiseptic or antibiotics on bacterial growth using agar plates and measuring zones of inhibition
1) Prepare your work area by sanitising the area using disinfectant and washing your hands2) Ignite the bunsen burner, setting it to a safety flame, and open available windows3) Open the vial containing the pathogen, such as bacillus subtillis, and spread it evenly around the agar gel using a spreader4) Soak a small circle of filter paper in the antipathogenic chemical (such as disinfectant or penicillin)5) Label the base of the petri dish and add your filter paper into the agar gel6) repeat steps 3-5 2 more times with a different antipathogenic chemical each time and place in a different corner of the petri dish7) Put the lid on the petri dish and seal it, turn the plate upside down so that the pathogen faces teh ground8) Place the plate into the incubator. Ensure the incubator is below 25*C9) Wait a few days and record your results and record in appropriate table/graph
73
Apparatus of Required practical:The effect of antiseptic or antibiotics on bacterial growth using agar plates and measuring zones of inhibition
Petri dish with agar jelly (sterile)
Bacteria culture (e.g. E. coli)
Inoculating loop or spreader
Discs of filter paper soaked in:
Different antiseptics (e.g. Dettol, mouthwash)
or antibiotics
Forceps
Marker pen + ruler
Incubator (usually at 25 °C for school safety)
74
How to calculate zone of inhibition
Pi x r^2
75
Control variables of Required practical:The effect of antiseptic or antibiotics on bacterial growth using agar plates and measuring zones of inhibition
Same bacterial strain and concentration
Same agar type and amount
Same size paper discs
Incubated for the same time and temperature
76
Independent variable of required practical microbiology
The type of antiseptic or antibiotic used
77
Dependent variable of microbiology required practical
The zone of inhibition — the diameter or area of the clear region around each disc
78
How can you prevent the spread of malaria?
The spread of malaria can be prevented by:
Using insecticide-impregnated nets to prevent mosquitoes biting humans and passing on the protists
Using insecticides to kill mosquitoes in homes and offices.
Preventing the vectors from breeding by removing standing water and spraying water with insecticides to kill the larvae
Travellers can take antimalarial drugs that kill the parasite in the blood if they are bitten by an infected mosquito.
by using mosquito nets to avoid
being bitten.
79
What is chlorosis caused by?
Magnesium ion deficiency
80
What 4 factors may cause stunted growth and yellowing of leaves?
Magnesium ion deficiency
Attacked by aphids
Disease
Nitrate ion deficiency
81
What molecules are required for growth?
Amino acids to make proteins for growth
82
How could someone ‘diagnose’ a plant disease?
Identification can be made by:
• Use a reputable gardening manual or website
• taking infected plants to a laboratory to identify the pathogen
• using testing kits that contain monoclonal antibodies.
83
Explain how a NITROGEN ion deficiency could affect a plant.
Lack of nitrogen: nitrogen (in the form of nitrates) are required by plants to make proteins.
Lack of nitrogen causes poor plant growth.
84
What are a plants CHEMICAL defence responses to resist invasion of microorganisms?
Antibacterial chemicals.
* Poisons to deter herbivores.
85
What are a plants MECHANICAL adaptations to resist invasion of microorganisms?
Thorns and hairs deter animals.
Leaves which droop or curl when touched.
Mimicry to trick animals.
86
What do bacteria and viruses do in the body
Bacteria and viruses may reproduce rapidly inside the body.
87
How is gonorrhoea spread
Gonorrhoea is spread by sexual contact.
88
The malarial protist has a life cycle that includes the ????
Mosquito
89
How are virus transported to animals and plants
Animals-Airborne droplets, contact, surfaces
Plants-Insects (vectors), wounds, pollen/seeds
90
How is bacteria transported to animals and plants
Animals-Food, water, contact, airborne
Plants-Water, insects, tools, wounds
91
How are protists spread to animals and plants
Animals-Vectors (e.g. mosquitoes)
Plants-Insects, seeds, water, wounds
92
How is fungi spread to animals and plants
Animals-Direct contact, spores in air
Plants-Airborne spores, water, tools
93
What happens if a pathogen trys to enter the body
If a pathogen enters the body the immune system tries to destroy
the pathogen.
94
Explain the role of the immune system in the defence against disease.
The immune system defends the body by:
White blood cells detecting and attacking pathogens.
Some white blood cells ingest and destroy pathogens using enzymes (phagocytosis).
Others produce antibodies that bind to specific antigens on pathogens and destroy them.
Some produce antitoxins that neutralise harmful toxins released by bacteria.
95
White blood cells help to defend against pathogens by:
• phagocytosis
• antibody production
• antitoxin production.
96
explain why numbers of bacteria
on an agar plate will eventually stop
growing.
Nutrient depletion,lack of space,competition,temperature changes
97
describe the difference between an
antiseptic, disinfectants and antibiotic.
Antiseptics: Chemicals used on living tissues (e.g., skin) to kill or slow the growth of microorganisms. Example: iodine, alcohol-based hand sanitizers.
Disinfectants: Chemicals used on non-living surfaces to kill microorganisms. They are too strong to be used on living tissues. Example: bleach, Dettol.
Antibiotics: Medicines taken inside the body to kill or stop the growth of bacteria. They do not work against viruses. Example: penicillin, amoxicillin.
98
explain when an antiseptic,
disinfectant, and antibiotic would be
used
Antiseptic-prevent infenction.Used on living tissues.Eg a cut
Disinfectant-used on non living surfaces to kill bacteria and viruses.
Eg:Table or tv remote
Antibiotic-Used inside the body to treat bacterial infections.
📌 Example: Taking penicillin to cure a throat infection caused by bacteria.
99
100
How to treat rose black spot
Remove infected leaves,improving air circulation,using fungicides,avoiding water on leaves
101
state how measles and HIV are
spread.
Bodily fluids,airborne droplets
102
Why are viral infections harder to prevent and treat than bacterial
Antibiotics only work on bacteria,viruses hide inside host cells,Fewer treatments for viruses
103
explain how a reduced or over
active immune system can cause illness.
Overactive Immune System (Attacking the Body)
Sometimes, the immune system overreacts or attacks the body’s own healthy cells, leading to autoimmune diseases.
Conditions like type 1 diabetes, rheumatoid arthritis, and lupus happen when the immune system mistakes normal body tissues as harmful.
104
suggest how plant diseases affect
food security.
Plant diseases reduce crop yield and quality, leading to food shortages and higher prices. They can also destroy entire crops, making less food available, which threatens food security.
105
Key stages of the malaria life cycle:
Mosquito bites an infected person and takes in the protist.
The protist reproduces inside the mosquito.
When the mosquito bites another person, the protist is passed into their bloodstream.
The protist travels to the liver and red blood cells, where it reproduces and causes symptoms (e.g. fever).
106
explain why it is so expensive to
stop the spread of malaria.
Vaccination problems,cost of medicines,insecticides
107
How to treat malaria
Malaria is treated with antimalarial drugs such as ACTs, which kill the Plasmodium protist in the blood. Early treatment is important to reduce symptoms and prevent the disease from becoming severe.
108
Can all pathogens be treated?
Bacterial, fungal, and protist diseases can usually be cured with specific medicines, but viral infections can only be treated or prevented with vaccines — they cannot be cured.
109
explain in detail how antibody
production fights pathogens.
When a pathogen enters the body, white blood cells called B-lymphocytes detect its antigens (unique surface markers). The correct B-lymphocyte binds to the antigen and starts rapidly producing antibodies, which are Y-shaped proteinsdesigned to attack that specific pathogen. Antibodies help by neutralizing toxins, clumping pathogens together (so they are easier to destroy), and marking them for destruction by white blood cells. After the infection is cleared, some B-lymphocytes become memory cells, allowing the body to respond faster and stronger if the same pathogen returns, providing long-term immunity.
110
What is phagocytosis?
The process by which white blood cells engulf and digest invading pathogens.
111
How can having one disease make you more susceptible to another?
Diseases like HIV damage the immune system, making it easier for other pathogens to cause illness.
112
What is the primary and secondary immune response?
The primary response is slow and produces fewer antibodies when first exposed to a pathogen. The secondary response is faster and stronger due to memory cells produced after the first exposure.
113
How is malaria prevented?
By using mosquito nets, insect repellents, draining standing water, and using insecticides to kill mosquitoes.
114
How do white blood cells fight infection?
By ingesting pathogens, producing antibodies to destroy specific pathogens, and producing antitoxins to neutralize toxins.
