Topic 5: Health and Disease

Question 1

What is the WHO definition of health?

Answer 1

A state of complete physical; mental; and social well-being not merely the absence of disease or infirmity

Question 2

What does communicable disease mean?

Answer 2

A disease that can be spread from one organism to another through pathogens

Question 3

What does non-communicable disease mean?

Answer 3

A disease that cannot be passed from person to person often caused by lifestyle or genetics

Question 4

Name some diseases caused by pathogens.

Answer 4

Cholera Tuberculosis Malaria Stomach ulcers Ebola Chalara ash dieback

Question 5

What is a virus?

Answer 5

A microscopic infectious agent that can only reproduce inside living cells consisting of genetic material surrounded by a protein coat

Question 6

Describe the basic structure of a virus.

Answer 6

Genetic material DNA or RNA inside a protein coat called a capsid

Question 7

What is the lytic cycle List steps?

Answer 7

1 Virus attaches to host cell 2 Virus injects genetic material 3 Host cell replicates viral components 4 New viruses assemble 5 Host cell bursts releasing viruses

Question 8

What is the lysogenic cycle List steps?

Answer 8

1 Virus inserts genetic material into host DNA 2 Viral DNA replicates with host DNA without harming cell 3 Environmental trigger activates virus 4 Virus enters lytic cycle producing new viruses

Question 9

Name some STI prevention methods.

Answer 9

Use of barrier methods such as condoms Regular screening Avoid sharing needles Taking prescribed medication

Question 10

What is HIV?

Answer 10

A virus that attacks the immune system specifically helper T-cells eventually leading to AIDS

Question 11

What are symptoms of HIV?

Answer 11

Flu-like symptoms initially later immune system weakens leading to infections and cancers

Question 12

How does HIV cause AIDS?

Answer 12

By destroying helper T-cells the immune system cannot respond effectively to infections

Question 13

What type of pathogen causes chlamydia?

Answer 13

Bacteria

Question 14

What are symptoms of chlamydia?

Answer 14

Often no symptoms possible genital discharge and pain during urination

Question 15

Give examples of plant physical defenses against pathogens.

Answer 15

Waxy cuticle Cellulose cell wall Bark on trees

Question 16

Give examples of plant chemical defenses.

Answer 16

Production of toxins that deter herbivores or kill pathogens such as caffeine poisons or antibacterial chemicals

Question 17

How can plant diseases be detected?

Answer 17

Observation of symptoms Analyzing distribution patterns Diagnostic testing for antigens or DNA of pathogens

Question 18

What are physical defenses in humans?

Answer 18

Skin barrier Mucus membranes Cilia in respiratory tract

Question 19

What are chemical defenses in humans?

Answer 19

Production of stomach acid Enzymes in tears and saliva that kill pathogens

Question 20

How does the immune system identify and fight pathogens?

Answer 20

B-lymphocytes produce antibodies that bind to antigens on pathogens phagocytes engulf and digest pathogens memory lymphocytes remember antigens for faster future response

Question 21

What is phagocytosis?

Answer 21

Process where phagocytes engulf and digest pathogens or foreign particles

Question 22

Define immunity.

Answer 22

The ability of the body to resist infection through the action of antibodies or sensitized white blood cells

Question 23

What is immunisation?

Answer 23

Introduction of a harmless form of a pathogen to stimulate immune memory without causing disease

Question 24

What are the benefits of immunisation?

Answer 24

Prevents disease Protects population herd immunity Reduces epidemics

Question 25

What are potential cons of immunisation?

Answer 25

Rare side effects Not 100% effective for everyone

Question 26

How are monoclonal antibodies made Step-by-step?

Answer 26

1 Inject antigen into mouse to stimulate immune response 2 Extract B-lymphocytes producing desired antibody 3 Fuse B-lymphocytes with myeloma cancer cells to form hybridoma cells 4 Grow hybridoma cells that produce antibodies indefinitely 5 Harvest monoclonal antibodies from hybridoma cultures

Question 27

How are monoclonal antibodies used in pregnancy tests?

Answer 27

They bind to hormone hCG in urine if hCG is present antibodies trigger a color change indicating pregnancy

Question 28

How are monoclonal antibodies used in cancer diagnosis?

Answer 28

They bind to specific markers on cancer cells allowing detection through imaging or tests

Question 29

How are monoclonal antibodies used in cancer drug delivery?

Answer 29

They deliver toxic drugs directly to cancer cells by binding to cell-specific antigens reducing damage to healthy cells

Question 30

How are monoclonal antibodies used to identify blood clots?

Answer 30

They bind to clot-specific proteins allowing detection or treatment targeting

Question 31

What is the role of antibiotics?

Answer 31

Kill or inhibit bacteria growth without affecting human cells

Question 32

Why don't antibiotics work on viruses?

Answer 32

Viruses use host cell machinery to reproduce and lack bacterial structures targeted by antibiotics

Question 33

What are the main stages of drug development?

Answer 33

Preclinical testing lab and animal tests Clinical trials testing on humans Placebo-controlled blind tests to check effectiveness and safety

Question 34

What is a placebo-controlled blind test?

Answer 34

A trial where one group receives the drug and another a placebo with participants or researchers unaware of who gets what to prevent bias

Question 35

What aseptic techniques are used in antibiotic testing?

Answer 35

Sterilising equipment with autoclave Flaming inoculating loop Keeping petri dish lids closed and taped Incubating petri dishes upside down to prevent condensation

Question 36

How does smoking increase cardiovascular disease risk?

Answer 36

Damages artery walls increases blood pressure reduces oxygen transport by carbon monoxide increases clot risk by sticky platelets

Question 37

What lifestyle factors increase cardiovascular disease risk?

Answer 37

Smoking Poor diet high fat or salt Lack of exercise Excess alcohol

Question 38

How is obesity measured?

Answer 38

Body Mass Index BMI and Waist-to-Hip Ratio

Question 39

What is cardiovascular disease CVD?

Answer 39

Diseases of the heart and blood vessels including heart attacks and strokes

Question 40

Why does CVD happen?

Answer 40

Build-up of fatty deposits called atheroma narrows arteries increasing blood pressure and clot risk damaging heart and brain

Question 41

How can lifestyle changes treat CVD?

Answer 41

Healthy diet Regular exercise Quit smoking Reduce alcohol intake

Question 42

How do statins treat CVD?

Answer 42

Lower cholesterol levels in blood reducing fatty deposits in arteries

Question 43

How do anticoagulants treat CVD?

Answer 43

Reduce blood clotting lowering risk of heart attack and stroke

Question 44

How do antihypertensives treat CVD?

Answer 44

Lower blood pressure reducing strain on heart and arteries

Question 45

Explain stent surgery.

Answer 45

A small mesh tube inserted into narrowed artery to keep it open and improve blood flow

Question 46

Explain coronary bypass surgery.

Answer 46

A healthy blood vessel from another body part is grafted to bypass blocked arteries restoring blood supply to heart muscle

Question 47

Explain heart transplant surgery.

Answer 47

Replacing a diseased heart with a healthy donor heart when other treatments fail