SB5 - Health, Disease and the Development of Medicine ✓ Flashcards Preview

Edexcel GCSE Biology > SB5 - Health, Disease and the Development of Medicine ✓ > Flashcards

Flashcards in SB5 - Health, Disease and the Development of Medicine ✓ Deck (43)
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1

SB5a - What are the three type of health?

  • Physical well-being: Being free from disease, getting regular excersize, limiting harmful substance etc.
  • Mental well-being: How you feel about yourself
  • Social well-being: How well you get along with others
  • M̶i̶n̶e̶c̶r̶a̶f̶t̶ ̶h̶e̶a̶l̶t̶h̶:̶ ̶R̶e̶g̶e̶n̶e̶r̶a̶t̶e̶s̶ ̶o̶v̶e̶r̶ ̶t̶i̶m̶e̶

2

SB5a - What is the difference between communicable and non-communicable diseases?

Communicable:

  • Caused by pathogens (microorganisms athat cause disease)
  • Can be spread between people

Non-communicable:

  • Caused by problems in the body and by lifestyle choices
  • Cannot be spread between people

3

SB5a - Why maya person be more likely to catch a disease if they've already got one?

  • One disease damages the immune system, making it easier for other pathogens to cause disease
  • A disease can damage the body's natural physical and chemical defences making it easier for pathogens to get in
  • A disease can stop an organ from functioning correctly, meaning other diseases are mroe likely to occur

4

SB5b - Define malnutrition.

A lack or excess of a specific nutrient in the body

5

SB5b - Describe the defficiency diseases associated with lack of:

  1. Protien
  2. Vitamin C
  3. Vitamin D and/or Calcium
  4. Iron

  1. Kwashiorkor: enlarged belly, small muscles, failure to grow properly
  2. Scurvy: Swelling/bleeding gums, muscle/ joint pains and tiredness
  3. Rickets/Osteomalacia: Soft bones/cruved leg bones
  4. Anaemia: Less and smaller red blood cells, tiredness

6

SB5b - Why is ethanol (in alcohol) considered a drug and what disease can it lead to?

  • It's considered a drug because it changes the way in which the body works
  • It can lead to liver cirrhosis which is a disease where the liver doesn't function properly

7

SB5c - Why is an obese person at a higher risk of developing CVD?

Obese people are more likely to have more body fat. More body fat increases risk of CVD

8

SB5c - What is CVD?

Cardiovascular disease is a result of the circulatory system functioning poorly and can lead to many side effects including high blood pressure, heart pains and even heart attacks

9

SB5c - What is BMI and what are its pros and cons?

  • A measure of weight relative to height calculated by mass ÷ height².
  • Its good at being a a measurement and comparison between people helping identify if they're over/underweight or obese etc.
  • However it doesn't take into account varying muscle and bone mass and so isn't always an accurate way of assesing risk.

10

SB5c - Describe how smoking can lead to blood clots.

  • Tabacco from smoking will damage artery linings.
  • Fat (or plaque) can build up in the artery wall making the artery narrow.
  • This will increase blood pressure
  • Eventually, the fat will block the whole artery
  • White blood cells will form a wall around this causing a clot leading to a heart attack or stroke

11

SB5c - Explain how a stent works.

  • A stent is a small mesh inserted into the artery on a delfated balloon.
  • Once in place, the balloon is inflated and the stent expands widening the artery
  • The balloon is taken out but the stent stays in keeping the artery wide

12

SB5d - Describe and explain the causes, types of baceria, host organisms and symptoms associated with:

  1. Cholera
  2. Tubercolosis(TB)
  3. Chalera dieback

  1. Caused by vibrio cholera (bacteria). It's hosts are animals/humans and it can lead to severe diarrhea and dehydration
  2. Caused by mytobacterium tubercolosis (bacteria). It's hosts are humans/animals. It damages lung tissue leading to coughing fever and tiredness
  3. Caused by the fungus chalara and affects trees/plants. Lesions on trunks and leaves die earlier than usual

13

SB5d - Describe and explain the causes, types of baceria, host organisms and symptoms associated with:

  1. Malaria
  2. Typhoid/dysentry
  3. Ulcers

  1. Caused by the plasmodium ptotist, it infects humans using moquitoes as a vector. Leads to fever weakness, sickness and lack of red blood/liver cells
  2. Caused by the salmonella typhi bacteria and infecting animals/humans causing severe diarrhea and dehydration
  3. Caused by the heliobacter pylori bacteria and infecting humans causing stomach ulcers

14

SB5d - Why are viruses not 'true organisms'?

They don't have a cellular structure and require hosts to survive

15

SB5d - Why are people with HIV likely to develop AIDS?

  • HIV attacks the white blood cells in your immune system making it weak.
  • Thus the immune system is inable to defend the body from secondary infections effectively

16

SB5f - Describe the lytic cycle.

  • Attachment: The viral particle attache sitself to the host receptor cell
  • Entry: Nucelic acid of the viruc moves across the membrane into the cell
  • Replication: The virus uses the host's DNA to replicate and synthesise new viral components
  • Assembly: The new viral components are assembled into new viruses
  • Release: Lysis of infected cell leads to release of fully assembled viral particles

17

SB5f - Describe the lysogenic cycle.

  • Attachment: The viral particle attache sitself to the host receptor cell
  • The Viral nuclei acids are incorporated into the DNA
  • The cell continues to divide
  • Replication: The virus uses the host's DNA to replicate and synthesise new viral components
  • Assembly: The new viral components are assembled into new viruses
  • Release: Lysis of infected cell leads to release of fully assembled viral particles

18

SB5g - What are the physical defences of plants?

  • Waxy layer called the cuticle
  • Cell walls

19

SB5g - What are the chemical defences of a plant (giving examples where appropriate)?

  • Poisons (in foxgloves)
  • Natural insect repellents/alarm substances (Wild potatoes)

20

SB5i - What are physical and chemical barriers?

  • Barriers to prevent pathogens from infecting the body.
  • Physical barriers stop them getting in and chemical barriers stop them from being effective.

21

SB5i - What are the physical and chemical barriers in the body?

  • Skin
  • Mucus
  • Earwax
  • Cilliated cells
  • Lysozyme (in saliva and tears)
  • Hydrochloric acid in the stomach

22

SB5i - What is lysozyme?

  • Lysozyme is an enzyme screted by skin and in tears and saliva.
  • It is chemical defence that breaks down the cell walls of types of bacteria.

23

SB5j - What are the two main types of white blood cells involved in the immune response?

  • Phagocytes
  • Lymphocytes

24

SB5j - How do phagocytes respond to pathogens?

  • They detect the pathogen and recognise it as a foriegn body.
  • They then ingest the pathogen and use enzymes to destroy it.

25

SB5j - How do lymphocytes respond to pathogens?

  • Lymphocytes have antibodies on their surface that are specific to the antigens present on certain pathogens
  • The lymphocyte with matching antibodies is activated and will attach to the pathogen and then divide making identical copies of itself
  • The lymphocytes secrete antibodies which attach to the antigens of the pathogen and destroy it
  • Some lymphocytes remain (Memory lymphocytes)

26

SB5j - Describe and explain the differences in primary and secondary response in terms of lymphocytes.

  • The primary response takes a long time between infection and rise in antibody numbers
  • The numbers of antibodies produced isn't that high
  • The number of antibodies doesn't return back to its original value but slightly higher instead
  • After the second infection, the secondary response is a lot quicker.
  • It also produces a lot more antibodies
  • This is because of the already active memory lymphocytes

27

SB5j - Why will memory lymphocytes created after one infection not affect the speed of response for an infection by a different pathogen?

The memory lymphocytes created after one infection have antibodies specific to the antigens of that particular pathogen and won't work on any othe pathogens.

28

SB5j - How does a vaccination work?

  • A vaccination injects inactive/weak pathogens of a disease.
  • Lymphocytes with antibodies to tackle these are activated and memory lymphocytes are created
  • This means that if that pathogen infects the person after, there will be memory lymphocytes to tackle it quiclkly
  • This increases the person's immunity to this disease as it reduces the severity of the symptoms and the time taken till the infection is dealt with

29

SB5j - If a child is allergic and cannot be vaccinated, how can they still ba safe from the pathogen?

  • If around 95% of the people around them are vaccinated there is a very low chance of them getting the disease.
  • This is because all the others either won't get it or will get rid of it before coming in contact with them.
  • This is called herd immunity.

30

SB5h - Which two methods may a farmer use to identify plant diseases?

  • Keys
  • Distribution analysis
  • Diagnostic testing