Health and disease Flashcards
What is health?
A state of complete physical, mental, and social well-being
What is a communicable disease?
A infectious disease that can be transmitted person to person or animal to person
Give 3 transmission types for a communicable disease.
- direct contact with an affected individual
- the individual’s discharge e.g. via droplet
- indirect (by a vector)
give two examples of communicable diseases.
Measles and malaria
What is a non-communicable disease?
A medical condition or disease that is not caused by infectious agents cannot be spread from person to person or animal to person
Give three example of non-communicable diseases.
asthma, cancer, CHD
Which two viruses can lead to cancer?
hepatitis, HIV
The spread of diseases can be reduced or prevented by ….. (name 4 factors)
- simple hygiene measures
- destroying vectors
- isolation of infected individuals
- vaccination
Give three more factors, other than disease, which affect your health.
- lifestyle: stress
- diet/exercise
- life environment
What is a risk factor?
a factor that increases the likelihood of someone getting a specific disease.
Which risk factor is shown to directly cause cardiovascular disease, lung disease and lung cancer?
Smoking
Which risk factor can lead to the development of Type 2 Diabetes?
Obesity:
- unbalanced diet
- lack of exercise
direct risk factors for coronary heart disease
- high saturated fat diet
- old age
- high cholesterol
direct risk factors for fetal alcohol syndrome
- high alcohol consumption by pregnant women
direct risk factors for liver failure
high alcohol consumption
direct risk factors for lung cancer, bronchitis and emphysema
- smoking
- high polluted environment
Name a risk factors in cancer
Carcinogens, including ionising radiation
What is the human cost of non-communicable disease?
millions die from them every year
What is the financial cost of non-communicable disease?
cost of researching or treating, cost of adapting or moving home, less people working
What is a casual mechanism?
one risk factor that may be partially responsible for a disease
What are causation factors?
Directly cause/relationship, proven for the risk
What is a correlation?
- there is an association between the two factors.
- Correlations are not the same as causation because they do not always mean a person will develop the disease
What causes cancer?
- uncontrolled cell growth and division (by mitosis)
- cause a mass of cells to develop which is called a tumour
What is a benign tumour?
- tumour continues to grow slowly until there is no space for any more cells
- remains at the site of origin.
- doesn’t invade other tissues
- Non-cancerous and not life threatening
What is a malignant tumour?
- tumours are cancerous+ grow quickly
- they invade neighbouring tissues
- spread to different parts of the body through the blood stream
- when they spread to another part of the body this is called a secondary tumour
-this is called a metastasis
How does a secondary tumour form?
- The cancer cells detach from the tumour
- enter the blood and spread through the body.
- Where they stop they begin to divide and multiply, creating another tumour.
Give 4 lifestyle risk factor for developing cancer.
- smoking: increase risk of lung, mouth, bowel, stomach and cervical cancer
- obesity: increased risk of bowel, liver+kidney cancer
- UV Exposure: increase risk of skin cancers
- viral infection: increased risk of liver cancer due to hepatitis B and C
Mutation in which genes can increase the risk of breast and ovarian cancer?
BRCA
Give four types of pathogen.
bacteria, viruses, protists, fungi
What is a pathogen?
Pathogens are microorganisms that cause infectious disease
- may infect plants or animals
- can be spread by direct contact , by water or air
Why do bacteria make you feel ill?
they produce toxins which damage the body cells
Why do viruses make you feel ill?
- reproduce inside body cells
- when the cell bursts the cell damage makes you feel ill.
- Once they have replicated inside the host cell the host cell ruptures and releases the new viral particles
are viruses classified as living or non- living and why?
They are often classified as non-living as they have to use to organelles in their host cell to reproduce.
Why do protists make you feel ill?
- All protists are eukaryotic and most of them are single celled
- Some protists are parasites - parasites live on or inside other organisms and can cause them damage which make us feel ill
what are 6 ways pathogens can be spread?
- direct contact
- indirect contact
- carried by vectors
- contact with contaminated food or water
- sexual contact
- bodily fluids
What is an organism which carries pathogens but doesn’t get a disease called?
A vector e.g an insect carries the protist (mosquitos carry malaria)
which kind of mosquito carries malaria?
Anopheles
Name diseases that are cause by viruses?
Measles, mumps, rubella, HIV
Bacteria reproduce rapidly by _______ ____________
binary fission
Give an example of single celled fungus
Yeast
Give examples of multicellular fungi?
Mushroom, athletes foot, mould, rhizo
What are cell wall of fungi made of?
Chitin (type of sugar)
what are the thread like structures in fungi called?
Hyphae: they can grow and penetrate human skin and the surface of plants, causing disease
How do fungi spread?
Hyphae produce spores, enabling the fungus to easily spread
How do fungi reproduce?
they reproduce asexually. They need gamets from mitosis
name 5 diseases caused by bacteria
- salmonella
- gonorrhoea (STD)
- bronchitis - affects the lungs
- meningitis - infection of the protective membrane that surround the brain
- cholera
How is salmonella spread?
- Found in raw meat: poultry, eggs, egg products (mayonnaise)
- undercooked food
- unhygienic conditions
Give four symptoms of salmonella.
Fever, stomach cramps, vomiting, diarrhoea
How can salmonella be treated?
- drinking fluids - replace lost fluids
- take rehydration salts - replace lost mineral ions and glucose
- antibiotics - severe cases
what are preventions of salmonella
- keep cooked food away from raw food - to prevent contamination
- cook food thoroughly
- wash hands thoroughly :
- after toilet
- after handling raw meat
Salmonella and gonorrhoea are what kind of disease?
Bacterial disease
Name 2 viral diseases
Measles, HIV & AIDs
What protist disease do we have to know about?
Malaria
How is gonorrhea transmitted?
- **sexual intercourse (STD) : unprotected sexual contact with an infected person
is there many symptoms of gonorrhoea in the early stages?
In the early stages it is relatively symptomless
- 10% of men, 50% of women had no obvious symptoms
Give common symptoms of gonorrhoea in women
- pain when urinating
- thick yellow/green vaginal discharge
- painful + tender lower abdomen
- bleeding between periods or after sex
Give common symptoms of gonorrhoea in men
- pain when urinating
- thick yellow/green discharge from penis
- inflammation of foreskin
- painful + tender testicles
What are the long term symptoms of gonorrhoea?
- infertility
- long term pelvic pain
- ectopic pregnancies (condition in which a fertilized egg grows outside of the uterus, usually in one of the fallopian tubes.)
- babies born from infected mothers have severe eye infections
How can we prevent the spread of gonorrhoea?
- use barrier contraception e.g. condoms, femidom
How can gonorrhoea be treated?
- treat with antibiotics
- but drug-resistance strain of bacterium is more common = more difficult to treat
what 4 diseases are caused by viruses?
- measles
- mumps
- rubella
- HIV
How are measles spread?
- Spread by inhalation of droplets of an infected person’s coughs or sneezes
- Viral particles in droplets are released into the air and an uninfected person inhales droplet.
What are the symptoms of measles?
- red skin rash
- fever
- headaches
- small- greyish spots on inside of cheeks
- sore red eyes, sensitive to light
What complications can measles lead to?
- sterility in adults
- fetal abnormalities in pregnant women
- brain damage inflammation of the brain (encephalitis)
How can measles be prevented and treated?
- no treatment
- vaccination - young children (~1 yrs old)
- infected person needs to be isolated
What does HIV stand for?
Human Immunodeficiency Virus
What does AIDs stand for?
Auto Immunodeficiency Disease
How is HIV transmitted?
- sexual contact
- exchange of bodily fluids such as breast milk, blood which occurs when drug users share contaminated needles
What are the early symptoms of HIV
- flu-like symptoms
- fever
- sore throat
- body rash
- tiredness
- joint and muscle pain
Usually person doesn’t experience any symptoms for a several years
What are the later symptoms of HIV
- weight loss
- chronic diarrhoea
- night sweats
- recurrent infections
How can HIV be treated?
Antiretroviral drugs - stops virus from replicating in the host cell
How does HIV develop into AIDs?
- virus enters lymph nodes and attacks the immune cells
- late stage of HIV, or AIDS, occurs when body’s immune system is no longer able to defend from other infections or cancers
How is malaria spread?
- female Anopheles mosquito feeds on blood of malaria infected animal
- ingests Plasmodium gamete cells (malarial protist)
- sexual phase of Plasmodium life cycle takes place in mosquito –> gamete’s fuse, mitosis takes place, sporozoites are produced and migrate to salivary gland
- infected mosquito feeds on uninfected human
- injecting saliva that contains protists (plasmodium sporozoites)
- protists infect liver cells and multiply asexually and cause live cells to rupture
- protists then infect red blood cells and reproduce asexually inside red blood cell
- infected red blood cell burst and infects other red blood cells
How can malaria be prevented?
- Insect repellent: helps to keep mosquitoes away, so less likely to get bitten
- Mosquito nets: keep mosquitos away while person is sleeping
What can be done to stop mosquitos breeding?
vector control: use of insecticides and pesticides or reduce mosquito numbers
treating water reserves where mosquitos breed
