Health, Disease, Defence Mechanisms And Treatments Flashcards
(68 cards)
1
Q
What is a microorganism? (2)
A
- microscopic organism or viral structure
- can be beneficial or harmful
2
Q
What is a pathogen?
A
A microscopic organism or virus that causes a disease
3
Q
What is a virus?
A
A non-living infectious agent that:
- invades and then
- replicates inside living cells
4
Q
What is a bacterium?
A
A single-celled organism that doesn’t contain a nucleus and is capable of causing disease
5
Q
How are bacteria structured?
A
- (peptidoglycan) cell wall
- cell membrane
- cytoplasm
- plasmids
- single chromosome
6
Q
what are communicable diseases?
A
Diseases that can be passed from one organism to another
7
Q
what are non-communicable diseases?
A
Diseases that cannot be passed from one organism to another
8
Q
what is health? (2)
A
When someone is free from
- communicable and
- non-communicable disease
9
Q
What type of microorganism is Chlamydia?
How is it spread?
How is it prevented / treated?
A
- bacteria
- sexual contact
- condoms for prevention
- Antibiotics for treatment
10
Q
What type of microorganism is salmonella?
How is it spread?
How is it prevented / treated?
A
- bacterium
- contaminated food
- Cooking food thoroughly (prevention)
- Not mixing cooked and uncooked foods (prevention)
- Antibiotics (treatment
11
Q
What type of microorganism is tuberculosis?
How is it spread?
How is it prevented / treated?
A
- bacterium
- airborne - by water droplets
- treated with drugs and antibiotics
12
Q
What type of microorganism is HIV?
How is it spread?
How is it prevented / treated?
A
- virus
- Infected blood
- Exchange of bodily fluids during sex
- Prevented by condoms
- Prevented by letting addicts use separate needles
- Controlled by drugs
13
Q
What type of microorganism are the cold & flu?
How is it spread?
How is it prevented / treated?
A
- virus
- airborne - by water droplets
- prevented by vaccination for targeted groups
14
Q
What type of microorganism is HPV?
How is it spread?
How is it prevented / treated?
A
- virus
- sexual contact
- vaccination given to teenagers
15
Q
What type of microorganism is athlete’s foot?
How is it spread?
How is it prevented / treated?
A
- fungus
- contact
- prevented by avoiding contact with surfaces likely to have spores - e.g. wear flip flops at a pool
- Treated with anti fungal creams
16
Q
What type of microorganism is potato blight?
How is it spread?
How is it prevented / treated?
A
- fungus
- spores in air
- prevented by crop rotation and spraying plants with a fungicide
17
Q
What is the body’s first lines of defence against infection?
Explain how each work (3)
A
- The skin - a barrier between pathogens and the blood
- Mucous membranes - secrete mucous which traps pathogens to be wafted out by cilia
- Blood clotting - barrier between blood and pathogens when wounds emerge
18
Q
What is the body’s second line of defence against infection?
A
The bloodstream - specifically white blood cells (Lymphocytes and Phagocytes)
19
Q
What is an antibody? (2)
A
- A structure produced by lymphocytes
- that has a complementary shape (and can attach to) the antigens on a particular microorganism
20
Q
What is an antigen? (2)
A
- A distinctive marker on a microorganism
- that leads to the body producing specific antibodies
21
Q
what is the primary response to infection in the blood? (2)
A
- antibody levels slowly increase after infection (illness shows)
- memory lymphocytes are produced
22
Q
what is the secondary response to infection in the blood? (2)
A
- memory lymphocytes trigger release of antibodies when known antigen enters bloodstream
- this occurs rapidly, with more antibodies produced than the primary response
23
Q
What is phagocytosis? (2)
A
- when antibodies clump to antigens
- phagocytes engulf and digest the microbe with enzymes in the phagocyte
24
Q
What is immunity?
A
When someone is protected from a particular infection or disease
25
What is **active immunity**? (**2**)
- where the **body produces antibodies itself**
- it is **slower acting** *than passive* but **lasts longer**
26
What is **passive immunity**? (**3**)
- when **antibodies** from **another source** are **injected** into the body
- **fast acting** but **lasts for a short period**
- also can be from **maternal milk**
27
What are **vaccinations**? (**2**)
**How** are they **made more reliable**?
1.
- when **dead/weakened pathogens** are **injected** into the **bloodstream**
- triggering an **increase in antibody levels** & production of **memory lymphocytes**
2. Booster vaccinations
28
What is the **difference** between a **primary** and **secondary response** to infection?
- secondary is faster
- secondary produces many more antibodies
29
**How** do **plants protect themselves** *against infection*?
(**2**)
1. Structurally:
- **waxy cuticle** prevent microbes entering
- as do **thick cell walls**
2. Chemically - *secreting* **antimicrobial chemicals**
30
**How** was **penicillin discovered**? (**3**)
- *Fleming* accidentally cultivated a **fungus** with bacteria in an agar plate
- the **fungus secreted a chemical** which **killed/inhibited the growth** of bacteria (seen through **area around fungus** with **no bacteria**)
- this was **penicillin**
31
What is penicillin an example of?
An antibiotic
32
**Who** was responsible for **isolating penicillin**?
Florey & Chain
33
What are **antibiotics**? (**2**)
- chemicals **produced by fungi**
- used to *kill bacteria* **or** *reduce their growth*
34
**Where** are **drugs** (like penicillin) **manufactured**?
Why are they produced at certain conditions?
- In industrial **fermenters**
- to prevent killing fungi / denaturing enzymes
35
What are the **two types of trials** used when *developing medicines*?
What are these followed by?
-
1. Preclinical trials
2. Clinical trials
- peer review
36
What are the **stages** of **preclinical trials**? (**2**)
1. **Testing drugs** on living **cells and tissues** in the lab (**in vitro**)
2. Using **animal testing** and **computer imaging**
37
**Why** are **preclinical trials used**?
- (stage 1) To **check** if the drug is **effective against** living **cells** *and* **isn’t toxic**
- (stage 2) to **check** the **effects** of the drug **on living organisms**
38
What are the **advantages** and **disadvantages** of **animal testing**? (**4**)
Advantages;
- avoids testing on humans
- can **check for side affects**
Disadvantages:
- drug *may react differently with humans*
- ethical issues
39
What happens during **clinical trials**? (**2**)
- firstly, **small numbers of healthy volunteers** are tested upon
- then **more people** use it, before **patients eventually** use it
40
What is the **purpose** of **clinical trials**? (**2**)
- to determine **efficacy** & the **optimum dosage**
- to find possible **side effects**
41
What is **peer review**?
When findings are **scrutinized by scientists** of **at least equal standing** *to the investigator*
42
When **penicillin** is produced in fermenters, what **process** is undertaken to distribute it?
**Downstreaming**:
- extraction
- Purification
- packaging
43
**How** does *bacteria* become **resistant** to antibiotics?
When **antibiotics** are **overused**, leading to the **development of superbugs** with **genetic mutations** *providing resistance*
44
What is **MRSA** an example of?
a **superbug**
45
How is **temperature** *kept constant* in a **fermenter**? (**2**)
- The **cold water jacket**
- which is **controlled by sensors**
46
Why are **superbugs hard to treat**? (**2**)
- They have **genetic mutations**
- which make them **resistant** to **several antibiotics**
47
*How* is **superbug spread reduced** in hospitals? (**3**)
- by **only using antibiotics** on **bacterial infection**
- by taking **care with hygiene** (*eg. Wearing gloves and cleaning spillages of bodily fluids immediately*)
- by **isolating patients** with superbugs
48
Outline aseptic techniques (**4**)
- **sterilising** Petri dishes, culture media, inoculating loops and culture bottles **by autoclaving, flaming** and **alcohol**
- **Petri dishes partially covered** (*when applying*) and **work near a Bunsen burner** during inoculation to *reduce the risk of contamination*
- **incubating** *sealed Petri dishes* at a **maximum temperature of 25°C** to *avoid* **growth of pathogens**
- **cleaning work surfaces and hands** and safely **disposing** of **bacterial cultures** by **autoclaving**
49
**How** do people *get* **non-communicable diseases**? (**2**)
- genetic **predisposition**
- lifestyle factors:
1. **Poor diet** (high in sugar & fat)
2. **Lack of exercise** (energy used in exercise less than intake)
3. **Overexposure to UV rays** (mutations lead to skin cancer)
4. **Misuse of drugs**
50
What are the **effects** of **overuse of alcohol**?
What is this called (overuse)?
-
1. Liver disease
2. Foetal alcohol syndrome
- binge drinking
51
What are the **effects** of **tar**? (**3**)
Causes:
- **bronchitis** - narrowing of bronchi and bronchioles
- **emphysema** - damage to alveoli reducing area for gas exchange
- **lung cancer** - carcinogens cause abnormal cell division
52
What are the **effects** of **nicotine**? (**2**)
- addictive
- affects heart rate
53
What is the **effect** of **carbon monoxide**? (**2**)
- **Combines with haemoglobin** in **red blood cells**
- which *reduces their oxygen carrying capacity*
54
How does a **heart attack occur**? (**6**)
- **cholesterol build** up on walls of **coronary arteries** leads to **narrowing**
- **increases** the **chance** of either **embolism or thrombosis**
- this **reduces** the **amount of blood** *carrying oxygen and glucose* to *coronary muscle cells* for **respiration**
- as a result the **coronary muscle cells die** (**myocardial infarction**)
- this means the **muscle cells** of the heart have to **work harder**,
- resulting in a **heart attack** once the **heart stops**
55
How does a **stroke occur**? (**5**)
- **cholesterol build** up on walls of **carotid arteries** leads to **narrowing**
- **increases** the **chance** of either **embolism or thrombosis**
- this **reduces** the **amount of blood** *carrying oxygen and glucose* to **neurons** for **respiration**
- as a result the **neurons die** (**infarction**)
- resulting in a **stroke** and **reduced brain function**
56
What **factors** *contribute to* **coronary heart disease**?
- stress
- excess cholesterol intake
- smoking
- lack of exercise
57
What is **angioplasty**?
When **dye** is **injected** *into the blood* to allow examination of diseased blood vessels
58
what are **stents**?
**Small, mesh-like structures** that are *inserted into a blood vessel* to keep the **lumen open**
59
**How** do **statins** *treat coronary heart disease*? (**2**)
- They **reduce blood cholesterol**
- and the **rate blood vessels** become **clogged** by cholesterol deposits
60
**How** does **aspirin** *treat coronary heart disease*? (**2**)
- **thins the blood**
- **reducing** the **chance of clots** forming in narrow blood vessels
61
What is **cancer**
and
what can it lead to?
- uncontrolled cell division
- tumours
62
What are the **2 types of tumour**?
Explain their properties
1. **Benign**:
- surrounded by a **capsule**
- **doesn’t spread** around the body
2. **Malignant**:
- **not surrounded** by a **capsule**
- **can spread** around the body
- due to **cells from primary tumour breaking away**
63
**Why** is it *important* to *detect cancer **early***? (**3**)
- The **tumour** will be **small** (hasn’t metastasized)
- and will have **caused less damage** to the body
- meaning there is a **greater chance of survival**
64
**How** can cancer be **treated**?
Describe each method
- **surgery** - removing cancer cells from the body
- **radiotherapy** - X-rays kill cancer cells
- **chemotherapy** - using drugs to kill cancer cells
- **immunotherapy** - antibodies attach to cancerous antigens followed by phagocytosis
65
What is/are the **advantage(s)** and **disadvantage(s)** of **surgery**? (Cancer)
Advantages :
- can swiftly remove small tumours
Disadvantages:
- **ineffective** if the **tumour has spread**
- or is in an **inaccessible part** of the body
66
What is/are the **advantage(s)** and **disadvantage(s)** of **radiotherapy**? (Cancer)
Advantage:
- very accurate against small tumours
Disadvantage:
- Normal cells can be affected
67
What is/are the **advantage(s)** and **disadvantage(s)** of **chemotherapy**? (Cancer)
Advantage:
- can kill cancer growth anywhere
Disadvantage:
- side affects like hair loss and killing memory lymphocytes, wiping out the immune system
68
What is/are the **advantage(s)** and **disadvantage(s)** of **immunotherapy**? (Cancer)
Advantage:
- reduced side affects
Disadvantage:
- cancer cells can have different types of antigens on their surface, so the treatment can be ineffective
