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GCSE biology 1 paper 1 > Health, Disease And The Development Of medicines > Flashcards

Health, Disease And The Development Of medicines Flashcards

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1
Q

What is the world health organisation (WHO) responsible for?

A

Coordinating ways to improve health across the world

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2
Q

According to the WHO organisation what is good health?

A

A state of complete physical, social and mental well-being

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3
Q

What does physical well-being include?

A

Being free from disease, eating and sleeping well, getting regular activity, and limiting the intake of harmful substances such as alcohol or drugs

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4
Q

What does social well-being include?

A

How well you get on with other people, and also how your surroundings affect you

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5
Q

What does mental well-being include?

A

How you feel about yourself

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6
Q

What is disease?

A

A disease is a problem with a structure or process in the body that is not the result of an injury

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7
Q

What causes diseases?

A

A disease might be due to microorganisms getting into the body and changing how it works. Microorganisms that cause disease are called pathogens. Diseases caused by pathogens are communicable disease, as they can be passed from an infected person to other people

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8
Q

What are non-communicable diseases?

A

Diseases that are not passed from person to person. They are caused by a problem in the body, such as a fault in the genes (such as cystic fibrosis) or as a result of the way we live - our lifestyle

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9
Q

Diseases may be correlated, so that having one diseas means a person is more likely to have another disease. What 3 possible causes of correlation might there be?

A

One disease damaging the immune system, making it easier for other pathogens to cause disease
A disease damaging the body’s natural barriers and defences, allowing pathogens to get into the body more easily
A disease stops an organ system from working effectively, making other diseases more likely to occur

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10
Q

What is genetic disorder?

A

It is a type of non-communicable disease that is caused by faulty alleles of genes. Genetic disorders can be passed to offspring but not to any other person

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11
Q

What is malnutrition?

A

It is a type of non-communicable disease that occurs when you get too little or too much of particular nutrients from your food. The lack of a certain nutrient can cause a specific deficiency disease

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12
Q

What is kwashiorkor?

A

It’s a disease caused by the deficiency of protein.
Symptoms include - enlarged belly, small muscles, failure to grow proper
Good sources in diet - meat, fish, dairy, eggs, pulses (eg lentils)

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13
Q

What is scurvy?

A

It’s a disease caused by the deficiency of vitamin C
Symptoms include - swelling and bleeding gums, muscle and joint pains, tiredness
Good sources in diet - citrus fruits and some vegetables

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14
Q

What is rickets or osteomalacia?

A

A disease caused by the deficiency of vitamin D and/or calcium
Symptoms of disease - soft bones, curved leg bones
Good sources in diet - vitamin D: oily fish, calcium: dairy products

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15
Q

What is anaemia?

A

A disease caused by the deficiency of iron
Symptoms of disease - red blood cells that are smaller than normal and in reduced number, tiredness
Good sources in diet- red meat, dark green leafy vegetables, egg yolk

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16
Q

How are some disease caused by our lifestyle?

A

It includes whether we take enough excessive and whether we take drugs. Eat hand,, found in alcoholic drinks, is a drug because it changes the way the body works. Ethanol is broken down by the liver, and a large amount of ethanol taken over a long period can lead to a liver disease including cirrhosis

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17
Q

What is cirrhosis?

A

Damage to the lives caused by drinking large amounts of alcohol over a long period of time.
A cirrhosis liver does not function well and can result in death. Liver disease is the fifth largest cause of death in the uk.

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18
Q

Malnutrition caused by a diet that is high in sugars and fats can lead to what?

A

Obesity,me here large amounts of fat are formed under the skin and around organs such as the heart and kidneys

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19
Q

What is cardiovascular disease?

A

A disease in which the heart or circulatory system does not function properly.
One sigh of this is high blood pressure, which can lead to heart pain or even a heart attack

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20
Q

What is a heart attack?

A

When the heart stops pumping due to a lack of oxygen reaching part of its muscle tissue

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21
Q

How do you work out body mass index (BMI)?

A

Mass ➗ height squared

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22
Q

What is body mass index?

A

An estimate of how health a persons mass is for their height. An adult who has a BMI of 30 or more is considered obese

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23
Q

What is the fat that seems to be most closely linked with cardiovascular disease?

A

Abdominal fat, diving waists measure meant by hip measurement to get waist-to-hip ratio gives a better method of measuring abdominal fat than BMI

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24
Q

Why is smoking so harmful?

A

Tobacco smoke contains many harmful substances that can damage the lungs when they are breathed in. Some of these substances are absorbed from the lungs into the blood and are transported around the body. These substances can damage blood vessels, increase blood pressure, make blood vessels narrower and increase the risk of blood clots forming in blood vessels. All of theses can lead to cardiovascular disease

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25
Q

How can a stent treat cardiovascular disease?

A

A narrowed blood vessel can be widened by inserting a small mesh tube (stent) at the borrowers part to hold it open. Blocked arteries in the heart can be bypassed by inserting other blood vessels so that the heart tissue is supplied with oxygen and nutrients. Patients who have these operations may need to take medicine for the rest of their life to prevent a heart attack or a stroke

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26
Q

High blood pressure increases the risk of cardiovascular disease. What may a doctor advise a patient with high blood pressure?

A

To exercise more and give up smoking. If blood pressure is very high, then the patient may be given medicines to reduce it

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27
Q

What is cholera?

A

A bacteria infection of the small intestine which causes severe diarrhoea.
Filipino pacini was the first person to isolate a bacterium from people with cholera and to suggest that the bacterium caused the disease
Robert Koch proved that vibrio cholerae cause the disease

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28
Q

What is tuberculosis?

A

A communicable bacterial disease that infects the lungs.
It’s caused by the bacterium mycobacterium tuberculosis. This bacterium infects and damages the lungs, resulting in blood specked mucus after coughing, fever (high body temperature) and weight loss

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29
Q

What do we say humans are the host of?

A

Communicable diseases

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30
Q

What is chalara dieback?

A

A disease of ash trees caused by a fungus

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31
Q

What is malaria?

A

A dangerous disease caused by a protist called plasmodium which multiplies inside red blood cells and liver cells, when a new protist breaks out of these cells it causes serious fever, headaches and vomiting and can lead to death.
This is one of the greatest causes of human death between 124 million and 283 million of malaria cases each year

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32
Q

What are viruses?

A

Particles that can infect cells and cause the cells to make copies of the virus. They are not true organisms because they do not have a cellular structure. They multiply by infecting a cell and taking over the cells DNA-coping processes to make new viruses. Different viruses infect different organisms, including bacteria. Virus infections often affect many parts of the body at the same time.

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33
Q

What does the Ebola virus cause?

A

Causes the breakdown of blood vessels and liver and kidney cells. This leads to internal bleeding and fever, so causing haemorrhaging fever

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34
Q

What does the human immunodeficiency virus (HIV) do?

A

It attacks and destroys white blood cells in the immune system. People infected with HIV often develop AIDS (acquired immune deficiency syndrome) because their immune systems cannot protect them from secondary infections. Many people die from these other infections, including TB

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35
Q

Many types of bacteria live in our bodies. Some are essential for our health, but others may not affect us most of the time. 50% of people have helicobacter pylori bacteria on their stomachs. What do 80% of these people never show symptoms of?

A

Of disease caused by these bacteria, but others may develop sore areas, called ulcers, where the bacteria attach the stomach lining

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36
Q

Most pathogens cannot grow outside their host, and so how must they spread?

A

From one host to another so they can increase in number. If we know how pathogens are spread, then we can find ways of stopping that spread

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37
Q

Infections such as colds, flu and tuberculosis cause a person to sneeze or cough. How do these infections spread?

A

This sends droplets containing pathogens into the air. Once in the air, flu viruses can survive for about a day. However TB bacteria can survive for months in air, and mix with dust that can blow around and infect another person.

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38
Q

How does fungi that causes chalara dieback spread?

A

In the air, as tiny spores (cells that grow into new organisms). Strong winds can carry chalara spores over long distances, such as to the southern uk from nearby Europe

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39
Q

What do some pathogens spread in?

A

In water,much as the bacteria that causes cholera, typos and dysentery (which all cause severe diarrhoea). These diseases are normally rare in developed countries, because the water that we use is treated to kill pathogens. We’ve got got hygiene. These diseases occur in very poor areas, after major environmental disasters, or in refugee camps

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40
Q

How can pathogens of the digestive system spread in food?

A

They enter he body through the mouth, which is described as the oral route. Helicobacter are though to be spread when people touch other people’s food after touching their mouths, or after going to the toilet. The bacteria may also spread on a fleet of flies that have fed on infected faces then landed on food

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41
Q

What is an epidemic?

A

When many people over a large are are infected with the same pathogen at the same time

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42
Q

What are vectors of disease?

A

Organisms that carry pathogens from one person to the next. Controlling the spread of the pathogen may involve controlling the spread of the vector

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43
Q

What do all viruses contain?

A

One or more strands of genetic material surrounded by a protein coat, or capsid, although many have additional layers surrounding the capsid

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44
Q

What is a capsid?

A

The protein coat of a virus

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45
Q

What are all viruses unable to do?

A

Replicate on their own. They have to enter a living cell and take over that cells processes for making new genetic material and proteins. Different types of virus take over different types of cells - some invade plant cells, others invade bacterial cells. Viruses that take over human cells include HIV and Ebola virus

46
Q

The cell copies the viral genetic material and makes new viral genetic material and proteins. What do these components assemble into?

A

Into new viruses, which then escape from the cell. Some types of virus cause the complete breakdown of the cell or lysis. Other types of virus leave by pushing out through the cell membrane. Both methods damage the cells, this causes disease. The viruses that have left the cells go and infect other cells

47
Q

What is lysis?

A

When the cell membrane of a cell breaks open, releasing everything inside the cell

48
Q

What is the lysogentic pathway?

A

The pathway in a virus life cycle where the virus genetic material inserts into the cells genetic material and is replicated each time the cell divides

49
Q

What is the lyric pathway?

A

The pathway where a virus enters a cell, takes over the cells replication process to produce more viruses, and cause lysis of the cell as the new viruses are released

50
Q

What is lysozyme?

A

An enzyme produced in tears, saliva and mucus that damages pathogens

51
Q

Go to page 107

A

And look at the cycles

52
Q

How can the effect of viruses on bacteria be studied?

A

Using bacteria lawn plates. These plates are made with nutrient agar, on top which a thin layer of bacteria grows. A solution containing viruses is added onto the l,ate. After a day or two, clear circles can be seen where bacteria have been killed by the virus. The larger the clear area, the more effective the virus have been at replicating and killing bacteria

53
Q

The is the cross-sectional area of a clear circle calculated?

A

Using pie r squared

54
Q

How do plants protect themselves from attach by pathogens?

A

The outer surfaces of leaves and stems are covered by a waxy layer called the cuticle. This layer acts as a physical barrier, making it difficult for pathogens to get to the cells beneath.

55
Q

What is a physical barrier?

A

A barrier that makes it difficult for pathogens to into the body

56
Q

If pathogens get through the barriers, they must then penetrate the tough cell walls to get inside the cells. How do some pathogens do this?

A

Some pathogens do this by releasing enzymes that soften the cell walls. Others infect parts of the plants that have weaker cell walls

57
Q

Physical barriers are not good protection against herbivores such as pests. What do many plants use instead?

A

Chemical defences. Some plants produce chemical substances to deter herbivores and pathogens only when they are attacked

58
Q

What a chemical defence?

A

The use of chemical compounds by organisms to defend against attacks

59
Q

What was aspirin originally produced from?

A

Salicylic acid, which is made by several plants, including meadowsweet and willow trees.
It’s commonly used to control symptoms of pain or fever

60
Q

What does the medicine Artemisinin do?

A

Kills the plasmodium protists that cause malaria. It was originally extracted from the wormwood plant, which has been used for centuries in Chinese herbal medicines to treat malaria

61
Q

Today most new medicines are produced using chemical substances in a lab. During development, new medicines are tested on cultures of bacteria or human cells. What must these test not be?

A

These tests must not be contaminated by microorganisms from the air and on equipment. A series of aseptic techniques are used, including the use of an autoclave to sterilise equipment and growth medium

62
Q

When do plants show signs of stress?

A

Whenever conditions are not good for growth, such as when there is too much or too little water, when the soil lacks nutrients, or when the plants are attacked by pests or diseases.

63
Q

What is stress in plants caused by?

A

Sometimes the stress may be caused by a combination of factors. Identifying the cause of the stress is essential so that the farmer can treat the crop correctly and prevent the loss of yield

64
Q

What is yield?

A

The amount of useful product

65
Q

How do cameras on drones help farmers?

A

They help the farmers find out if crop plants are under stress

66
Q

How does identify the cause of stress in a plant begin?

A

Usually begins with careful observation of the plants, looking for visible symptoms. These can include changes in growth, changes in colour or blotching of leaves, or lesions (areas of damage) on stems or leaves

67
Q

What will diseases that spread by the wind affect?

A

Affect plants over a wide area, though most obviously where the wind first reaches the crop.

68
Q

When are soil pathogens found?

A

Usually found in small areas, and so create an obvious pattern of damaged plants

69
Q

How can distribution analysis help?

A

It looks at wher the damaged plant occurs

70
Q

What will flooding, drought or lack of soil nutrient create?

A

Similar symptoms in all the plants in the area

71
Q

Sometimes, the only way to get a definite indentification of a crop is what?

A

To send samples to a lab for testing. The test should allow a diagnosis of the problem.

72
Q

What do the tests for crop disease include?

A

Includes trying to identify the presence of genetic material from a pathogen. When farmers send damaged plants for testing, they will also send a report about the other observations they have made. They may also send soil samples to be tested for nutrients and toxins, this diagnostic testing helps the lab to be more certain of the cause of the problem

73
Q

How is skin a physical barrier against the attack of pathogens on the body?

A

It is very thick over most of the body. Pathogens can usually only cross this barrier through wounds or bay an animal vector that pierces the skin. The skin is a physical barrier because pathogens have difficulty getting past it

74
Q

What chemical defence does the body have against pathogens?

A

It contains substances onto the skin surface. These substances include lysozyme, which is an enzyme that breaks down the cell walls of some type of bacteria. Lysozyme is a chemical defence because it reacts with substances in the pathogen and kills the pathogens or makes them inactive

75
Q

Where is lysozyme secreted?

A

In tears (from the eyes), saliva (in the mouth), and in mucus, where it helps to protect the thinner surfaces of the body

76
Q

What is mucus?

A

A sticky secretion produced by cells lining the many openings, such as the mouth and nose, that pathogens could use to enter the body. Dust and pathogens get trapped in mucus

77
Q

What are Ciliated cells?

A

They are specialised cells to move substances such as mucus across their surfaces. This helps to carry dust and pathogens away, either out of the body or into the throat where they enter the digestive system

78
Q

What does the hydrochloric acid longing the stomach do?

A

It destroys many pathogens. In.y a few types of bacteria, such as helicobacter pylori are adapted to survive in the stomach

79
Q

What natural defences does the reproductive system have?

A

Lysozyme in vaginal fluid and mucus. However some pathogens overcome these defences. These pathogens are usually transmitted through sexual activity and are called sexually transmitted infections.

80
Q

How can the pathogens HIV virus and chlamydia bacterium be spread?

A

By contact with sexual fluids (semen or vaginal fluid). This method of transmission can be reduced or prevented by avoiding direct contact with sexual fluids, such as a condom. Both of these pathogens may also be passed from a pregnant mother to her unborn baby. HIV may also be passed from an infected person into others blood, such as through sharing needles when injecting drugs

81
Q

What is chlamydia?

A

A bacterium that causes a sexually transmitted infection

82
Q

How does screening help people with STIs?

A

Many people with STIs are not aware they are infected. Screening helps to identify an infection so people can be treated for the disease

83
Q

What does blood given to people who have lost a lot of blood need to go through before its given to someone?

A

It is screed to make sure it doesn’t have HIV particles or other pathogens

84
Q

What is screening?

A

Tests on samples of body fluids to check if people have a certain condition like a STI

85
Q

What is the job of the immune system?

A

To attack the pathogen and try to prevent them causing harm

86
Q

What do all cells and virus particles have?

A

Molecules on their outer surfaces called antigens. The immune system uses these antigens to identify if something inside the body is a cell of the body has come from outside

87
Q

What is an antigen?

A

A protein on the surface of a cell. White blood cells are able to recognise pathogens because of their antigens

88
Q

What is the process of pathogens being attacked in the immune system?

A

Pathogens have antigens on their surface, are unique to them
A lymphocyte with an antibody that perfectly fits the antigen is activated
This lymphocyte divides over and over again to produce clones of identical lymphocytes
Some of the lymphocytes secrete lots of antibodies which stick to antigens and destroy the pathogen. Other lymphocytes remain in the blood as memory lymphocytes, ready to respond immediately if the same antigen ever turns up again

89
Q

What are lymphocytes?

A

A type of red blood cell that produces antibodies

90
Q

What are antibodies?

A

A protein produced by lymphocytes. It attaches to a specific antigen on a microorganism and helps to destroy or neutralise it

91
Q

What is a memory lymphocyte?

A

A lymphocyte that remains in the blood for a long time after an infection or vaccination

92
Q

What is a secondary response?

A

The way in which the immune system responds on the second occasion that a particular pathogen enters the body

93
Q

What is a secondary infection?

A

An infection due to the immune system being weakened previously by a different pathogen

94
Q

immunity to a pathogen (immunisation) can be triggered artificially, by using a vaccine. The vaccine contains weakened or inactive pathogens, or bits of the pathogen that include the antigens. How does the vaccine get into your body?

A

The vaccine may be injected into the body, or taken by mouth, and usually causes little reaction. Most vaccines will protect against particular diseases for many years

95
Q

In very few cases of immunisation will someone react badly to a vaccine. If there is a known risk that a child might react badly, then that child may not be given the vaccine. How will they be protected?

A

They will still be protected is 95% of other children are immunised, because their chance of coming into contact with another infected person will be ver low. This is known as herd immunity

96
Q

What is herd immunity?

A

When the majority of people in a group are immunised, which provides protection to the few who are not by reducing their chances of meeting an infected person

97
Q

What are antibiotics?

A

Substances that either kill bacteria or inhibit their cell processes, which stops them growing or reproducing. Antibiotics do not have this effect on human cells. This makes them useful for attacking bacterial infections that the immune system can’t control

98
Q

What one the first antibiotic and who discovered it?

A

Penicillin and Alexander Fleming 1928, he noticed something strange on an agar plate covered in bacteria he’d left for several weeks. Where mound had grown and bacteria had been killed, he discovered the mound was penicillin

99
Q

Many kinds of antibiotic have been developed that works in different ways. Why is this important?

A

Because different types of bacteria have different structures and they do not all respond in the same way to a particular antibiotic

100
Q

What is a major problem with using antibiotics?

A

Bacteria are evolving resistance, they are no longer harmed by the antibiotic. New antibiotics and medicines must be developed to fight infection

101
Q

What is the first step in the development of a possible new medicine?

A

When it is tested on cell or tissues in a lab. This is the first pre-clinical stage of testing. This stage shows is the medicine can get into the cells and have the required effect. All medicines have side effects, causing unintended changes that may be harmful. So testing tries to make sure that harmful side effects are limited

102
Q

If the pre-clinical stage is successful what is the medicine tested on?

A

Animals to see how it works in a whole body. If that stage is successful, the Medicine is tested in a small clinical trial, on a small number of healthy people, to check that it is safe and that side effects are small

103
Q

If the small clinical trial is successful, what happens next?

A

The medicine is used in a large clinical trial, on many people who have the disease that the medicine will be used to treat. This helps to work out the correct amount to give (the dose), and to check for different side effects on different people. Only if a new medicine passes all these tests can a doctor prescribe it for patients

104
Q

What are monoclonal antibodies?

A

Many identical antibodies

105
Q

Monoclonal antibodies cannot be made in large amounts using normal lymphocytes. Although a lymphocyte can divide over and over again to make copies of itself (clones), once it has started to produce antibodies it cannot divide anymore? How can we get around this problem?

A

Hybridoma cells are made by fusing a lymphocyte that produces the right kind of antibodies with a cancer cell. Cancer cells are used because they can divide over and over again. Hybridoma cells have the characteristics of the lymphocyte and the cancer cells they we made from

106
Q

What are hybridoma cells?

A

A cell made by fusing a lymphocyte and a cancer cell

107
Q

How are monoclonal antibodies made?

A

A particular antigen (for example a human hormone) is injected into a mouse. The mouse produces lymphocytes that me antibodies against the human hormone
Then the lymphocytes are fused with cancer cells to make a hybridoma cell
The hybridoma cell can both divide and make antibodies against a the human hormone. These are monoclonal antibodies

108
Q

How can monoclonal antibodies be made?

A

They can be made to match and stick to any kind of protein, such as hormones and enzymes. They can be made to march the antigens on pathogens (helps identify the pathogen). They can also be made to stick to specific cells in the body such as cancer cells or platelets (platelets are fragments of blood cells that form blood clots. In wrong places, such as the brain or heart, these clots can kill)

109
Q

Since monoclonal antibodies can be made to stick to certain types of cell, what can they be used in?

A

Medical diagnosis. This is often done by making the antibodies slightly radioactive. When the antibodies attach to cancer cells, the radioactivity can be detected (by a PET scanner for example) and so the position of cancer can be found

110
Q

Why are cancer drugs attached to monoclonal antibodies?

A

So they are delivered just to the cells that need treating. This reduces the amount of drug needed to kill the cancer cells and reduces the risk of damaging healthy cells

GCSE biology 1 paper 1 (5 decks)

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