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GCSE Biology (B1) > Keeping Healthy > Flashcards

Flashcards in Keeping Healthy Deck (52)
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0
Q

If someone’s diet is unbalanced they are…

A

Malnourished

1
Q

What comprises a balanced diet?

A
  • Carbohydrates,
  • Protein
  • Fibre
  • Fats
  • Vitamins
  • Minerals
  • Water
2
Q

Define ‘metabolic rate’

A

The rate at which reactions in the body take place.

3
Q

What effects metabolic rate?

A
  • Inherited factors (e.g. genes)
  • Muscle to fat ratio
  • Exercise
4
Q

How do people become obese?

A

Taking in more energy than is used

5
Q

Type 2 diabetes is caused by…

A

Long term obesity

6
Q

What problems does starvation cause?

A
  • Difficulty to walk around + do things (due to lack of energy)
  • Deficiency diseases (scurvy etc)
7
Q

Name two inherited factors that effect our health

A

Metabolic rate and cholesterol levels

8
Q

How many types of cholesterol are there?

A

2, ‘good’ and ‘bad’

9
Q

What does ‘good’ cholesterol do?

A

It is used in cell membranes and to make other vital substances

10
Q

What does ‘bad’ cholesterol lead to?

A

Heart disease

11
Q

What effects cholesterol levels?

A
  • Inherited factors
  • The amount of foods rich in saturated fats consumed by a person
  • Exercise
12
Q

Excess energy (sugar) is stored in the body as _____ which leads to _______

A

Fat, which leads to weight gain

13
Q

What are pathogens?

A

Microorganisms that cause infectious diseases

14
Q

Most pathogens are…

A

Bacteria or viruses (however some can be fungi)

15
Q

At what rate to bacteria and viruses reproduce?

A

Rapidly

16
Q

How do pathogens make you feel ill?

A

They produce toxins.

Viruses also reproduce inside cells, damaging the cells and making you feel ill.

17
Q

Explain how Semmelweiss helped stop the spread of pathogens.

A
  • Semmelweiss noticed that pregnant women whose babies were delivered by midwives didn’t get Puerperal Fever as often as those treated by doctors.
  • He asked doctors to wash their hands before they delivered babies and treating patients Many worked in morgues so they were carrying the germs from the dead bodies.
  • This led to less cases of Purperal Fever.
  • Many doctors didn’t believe him.
18
Q

List three ways the body prevents pathogens from entering

A
  • The skin
  • Trapping in mucus
  • Killed by stomach acid
19
Q

List three ways white blood cells defend against/ destroy pathogens

A
  • Ingest pathogens (phagocytosis)
  • Produce antibodies (lymphocytes)
  • Produce anti toxins
20
Q

What do antibiotics kill?

A

Bacteria

21
Q

Who discovered Penicillin and when?

A

Alexander Fleming, 1928

22
Q

Why are viruses difficult to kill?

A

Because they reproduce inside body cells, so treatment may damage the body as well

23
Q

Why might a scientist grow a culture of non-pathogenic bacteria?

A

To test the effects of different antibiotics and disinfectants

24
Q

Why must equipment used to grow bacteria be sterilised?

A

To ensure nothing is contaminated with unwanted microorganisms, such as pathogenic bacteria

25
Q

What is needed in order to grow a culture of bacteria?

A
  • A culture medium, usually agar jelly
  • Oxygen
  • Constant temp of 25 °C in schools, 35 °C in industry
26
Q

What is a culture medium?

A

A liquid or gel containing nutrients, such as carbohydrates, minerals, and sometimes other chemicals

27
Q

Why can schools only grow bacteria at 25 °C?

A

To stop rapid/out of control growth in case the culture is contaminated

28
Q

Explain the steps of sterile technique

A
  • Sterilise the inoculating loop used to transfer the microorganisms onto the agar jelly by dipping it into ethanol and then heating it until it’s red hot
  • Dip the loop into the bacteria you want to grow, then remove the lid of the Petri dish partially. Make zigzags across the agar with the loop. Replace the lid of the agar quickly to prevent microorganisms from the air contaminating the culture
  • Seal the Petri dish with tape to prevent microorganisms from the air entering, and bacteria from the culture escaping
  • Do not seal the dish completely so oxygen can enter. Without oxygen, harmful anaerobic bacteria can grow (with oxygen they don’t)
29
Q

When a pathogen changes, it’s called a…

A

Mutation

30
Q

Why do mutations cause problems?

A

Because not many people are immune to them, this can cause the mutation to spread very quickly

31
Q

Define an ‘epidemic’

A

When more cases of an infectious disease are reported than normal in one country

32
Q

Define a ‘pandemic’

A

An outbreak of an infectious disease causing more cases than normal across several countries

33
Q

How do anti biotic resistant bacteria develop?

A
  • A bacterium mutates, causing it to be antibiotic resistant.
  • All other bacteria are killed off by antibiotics.
  • The resistant bacterium survives and reproduces, creating a whole population of resistant bacteria.
34
Q

Why is it important to take a whole course of antibiotics?

A

To ensure that all the bacteria are killed so none are still alive and able to develop resistance to the antibiotic.

If a small number is left, the body can kill them however large numbers are problematic.

35
Q

What forms of pathogens are used in vaccines?

A

Dead or dormant pathogens

36
Q

What is a vaccine?

A

The dead or inactive pathogen material used in vaccination

37
Q

Define vaccination.

A

Introducing small quantities of dead/inactive pathogens into the body to stimulate the white blood cells to produce antibodies that destroy the pathogens. This makes the person immune to future infection.

38
Q

How are vaccinations usually administered?

A

They are injected into the body

39
Q

What happens when a vaccine is injected into the body?

A

White cells react by producing anitbodies

40
Q

What types of pathogens can vaccinations protect against?

A

Viral or bacterial pathogens

41
Q

What does MMR prevent?

A

Measels, mumps, and rubella

42
Q

What is an antigen?

A

Protein shape/marker on the surface of a cell (such as a pathogen or red blood cell)

43
Q

How do vaccines protect you against pathogens?

A
  • Small amounts of dead/inactive pathogens are put into your body (often by injection)
  • The antigens on the pathogens stimulate your white blood cells into making antibodies, which destroy the pathogens.
  • This means that you do not get the disease.
  • You are also immune to future infections because your body stores copies of the required antibodies in ‘memory’ white blood cells. This means it can respond rapidly if you ever get the disease again.
44
Q

How do we protect society from very serious diseases?

A

By vaccinating most people in the population

45
Q

Who does vaccination protect against disease?

A

Individuals, but also wider society as they are less likely to be spread

46
Q

What long term damage can measels cause?

A

Deafness and sometimes death

47
Q

What are the disadvantages of vaccination?

A
  • Can cause mild or serious side-effects
  • Don’t always work
  • Everybody needs to be vaccinated in order to fully eradicate a disease
  • They cost money to produce and administer
  • They can be unpleasant/painful to recieve
  • People need to be trained in how to administer them
48
Q

What are the advantages of vaccination?

A
  • They prevent disease
  • They are beneficial to wider society - the more people vaccinated the less likely everyone is to catch that disease
  • They normally work
  • They give you immunity safely without you having to actually catch the disease properly
  • They can be given to babies and small children safely to give them immunity
49
Q

What can the overuse of antibiotics lead to?

A

The development of new strains of bacteria, some of which are antibiotic resistant

50
Q

What do doctors not prescribe antibiotics for?

A

Mild infections such as minor sore throats

51
Q

What are scientists always trying to find?

A

New ways of treating disease!