B9: Animal physiology 5

Question 1

Communicable diseases

These are diseases that are:

Answer 1

infectious (are caught)
and
caused by pathogens.

Question 2

Pathogens cause disease and include:

Answer 2

1) viruses
2) bacteria
3) protists
4) fungi.

Question 3

HIV can be passed from one person to another through

Answer 3

infected body fluids that contain the virus.
It can enter a person across mucous membranes or if the skin of a person is broken.
For example, the virus can be passed between people in semen or vaginal fluid so can be considered a sexually transmitted infection/disease.
However, it could be transferred in infected blood or breast milk.

Question 4

prevention of infection with HIV would be by stopping the transmission of infected body fluids. This can be by:

Answer 4

using a condom during sexual intercourse
an HIV-infected mother bottle feeding her baby rather than breast feeding
screening blood so infected blood is not used in a blood transfusion.

Question 5

people can be given …..that stop reverse transcriptase from functioning.=

Answer 5

anti-retroviral drugs.

less HIV with functioning reverse transcriptase, new HIV will not be made so the HIV infection can be controlled.

Question 6

spread of influenza

Answer 6

airborne droplets of sputum
sneezed or coughed out of an infected person
inhaled by an uninfected person.
also be caught through contact.

Question 7

influenza preventio

Answer 7

covering the mouth and nose when sneezing
or coughing or wearing a mask if infective,
and frequent hand washing to reduce potential transfer from surfaces.

Question 8

influenza symptoms

Answer 8

runny nose, fever, sneezing, coughing and a sore throat a few days after infection but these should subside within about a week.

Question 9

influenxa treatment

Answer 9

Vaccines - inactive virus or weakened virus
are available to groups at risk such as those with a weakened immune system. Vaccination can help to avoid pandemics.

Antiviral drugs are available to tackle influenza in some circumstances.

Question 10

measles spread

Answer 10

direct contact such as touching an infected person.
airborne mucus droplets expelled - sneezing and coughing by an infected person
inhaled by an uninfected person.

Question 11

measles symptoms

Answer 11

reddish blotchy rash that tends to start in the head/neck region, spreads over the face
then can cover the full surface of the skin.
a sensitivity to light.

Question 12

measles treatment

Answer 12

can be prevented by the MMR vaccine which uses live weakened viruses for measles, mumps and rubella (German measles).

Question 13

tmv spread

Answer 13

one plant to another by direct contact,
via an insect such as an aphid.
The virus can also remain in the soil for some time.

Question 14

tmv prevention

Answer 14

stop viral transmission
by removing infected plants,
washing hands after touching an infected plant
through crop rotation.

Question 15

tmv symptoms

Answer 15

cause tobacco leaves to have light and dark green areas (mosaic)
and they may become wrinkled.

Question 16

tmv treatment

Answer 16

may also be infected with a milder strain of TMV which acts like a vaccine, preventing a more damaging strain.

Another approach is to genetically modify the tobacco plant to make it resistant to the disease.

Question 17

Salmonella food poisoning spread

Answer 17

occur when a person ingests food contaminated with the bacterium.
The bacterium survives the low pH conditions of the stomach and reproduces in the small intestine where it causes inflammation.

Question 18

Salmonella food poisoning prevention

Answer 18

proper food preparation such as washing hands after handling raw meat,
making sure that frozen meat is thoroughly defrosted before cooking,
and that food is thoroughly cooked.

Question 19

Salmonella food poisoning treatment

Answer 19

Most people recover without treatment, but sometimes oral rehydration supplements are given to replace lost electrolytes.

Question 20

Salmonella food poisoning symptoms

Answer 20

diarrhoea, vomiting and fever.

Question 21

plasmodium s-causes malaria.- spread

Answer 21

spread by mosquitoes infected with theprotist mosquito can bite an infected human, to gain blood.
If they take in the protist, then it can be transferred to another human (or a variety of other mammals) at the next bite.

Once a human has the protist, it enters the liver where it matures.
It then moves into red blood cells where it reproduces. The red blood cells rupture, releasing the protists which then infect more red blood cells. This reproduction/release can happen in regular cycles leading to the periodic fever associated with malaria

Question 22

fungal disease spread

Answer 22

The fungus produces large numbers of spores asexually
which disperse into the air and are then breathed in.

Symptoms include fever, cough, chest pain and breathlessness, usually in humans with a weakened immune system such as those with HIV or asthma.

Treatment uses medication such as steroids or antifungal medication. However, some strains have developed resistance to the medication.

Question 23

fungal disease prevention

Answer 23

reducing exposure to the growing fungus,

such as regulating food storage in dry conditions which prevent fungal growth.

Question 24

fungal disease symptom

Answer 24

fever, cough, chest pain and breathlessness,

usually in humans with a weakened immune system such as those with HIV or asthma

Question 25

fungal disease treatment

Answer 25

medication such as steroids or antifungal medication. However, some strains have developed resistance to the medication.

Question 26

preclinical tests

Answer 26

– do not involve testing on humans

Question 27

clinical tests

Answer 27

– do involve testing on humans.

Question 28

1) why is medicine tested on animals

Answer 28

to make sure safe to test on humans

Question 29

2) why medicine tested on few healthy people phase 1

Answer 29

to make sure safe- low no. reduced risk | look for obvious side effects

Question 30

3) why medicine tested on few healthy patients phase 2

Answer 30

to make sure works low no. reduced risk look for side effects

Question 31

4) why medicine tested on many peope as a double- blind trial with placebo

Answer 31

look for less common side effetc s double- blind to remove bia s placebo to compare effect of medicine against placebo effect

Question 32

define placebo effect

Answer 32

positive effect gained from taking the placebo. | If the chemical being tested does work, its positive effect should be greater than the placebo effect

Question 33

Non-communicable diseases These are diseases that:

Answer 33

are not infectious – they cannot be passed from one person to another are caused by the interaction of many different factors.

Question 34

Some non-communicable diseases are:

Answer 34

1) cardiovascular disease 2) many forms of cancer 3) some lung diseases 4) some liver diseases 5) nutrition-influenced diseases.

Question 35

a) Coronary heart disease

Answer 35

coronary arteries are very narrow blood vessels If any of their branches become blocked, then the heart muscle cells after the blockage will not receive oxygen and glucose and begin to carry out anaerobic respiration. If this continues, these cells may die, leading to reduced heart function.

Question 36

The blockage is usually

Answer 36

a fatty deposit called atheroma, or a blood clot.

Question 37

Hypertension

Answer 37

consistently raised blood pressure (above 140/90 mmHg). may be due to the narrowing of an artery lumen due to atheroma or hardening of an artery so that it cannot expand when blood flow increases.

Question 38

Stroke

Answer 38

part of the brain is deprived of oxygen-rich and glucose-rich blood, so brain cells die. reason for the lack of blood is often due to narrowing and/or hardening of arteries supplying the brain tissue.

Question 39

Some risk factors that can be modified:- cardiovascular

Answer 39

``` diet – consumption of foods high in fat/cholesterol increase risk of atheroma; and a high salt intake increases the risk of hypertension too little exercise obesity smoking excess alcohol intake. ```

Question 40

Some risk factors that cannot be modified:- cardivasculae

Answer 40

increasing age gender heredity/a family history of CVD.

Question 41

Statins

Answer 41

reduce the production of cholesterol, which is a component of atheroma. Build-up of atheroma can lead to blocked arteries.

Question 42

Anti-coagulants

Answer 42

They reduce the likelihood of blood clotting | and therefore blocking an artery.

Question 43

Anti-hypertensive drugs

Answer 43

They can cause blood vessels to relax so their lumen diameter enlarges, reducing blood pressure.

Question 44

stenr

Answer 44

place a mesh tube into a narrowed part of a coronary artery to increase its lumen diameter so there is no restriction in the flow of blood to the cells it supplies.

Question 45

bypass

Answer 45

A small section of blood vessel is removed from another part of the body. It is then used to re-route blood around a blockage in a coronary artery.

Question 46

prostate cancer risk factors

Answer 46

being overweight eating a lot of red meat or high-fat dairy products increasing age family history of this form of cancer

Question 47

breast cancer risk factors

Answer 47

being overweight increasing age family history of this form of cancer BRCA 1 or 2 gene mutation

Question 48

colorectal cancer risk factors

Answer 48

being overweight a diet low in fibre increasing age family history of this form of cancer

Question 49

Type 2 diabetes risk

Answer 49

When a person eats food high in sugar, their blood glucose level will consequently rise and the pancreas responds by releasing insulin. However, if this is done on a regular basis, their body, including muscle cells, become increasingly resistant to the insulin released. Therefore, less insulin may be produced, leading to a persistently raised blood glucose level and the release of more glucose in the urine. In addition to eating foods high in sugars, other risk factors for type 2 diabetes include being overweight, insufficient exercise and a family history of the disease.