Health and Disease Flashcards
What are microbes?
Microbes or micro-organisms are living things that are so small that they can only be seen through a microscope.
What are the three type of microbes?
bacteria, fungi and viruses
How can microorganisms be useful to society?
needed for decay, making alcohol, bread and yogurt and maintaining a healthy digestive system
What are disease causing microorganisms called?
Pathogens
What microbe causes HIV?
Virus
What is the transmission method for HIV?
Unprotected sex
Mixing of blood
From mother to child during childbirth or breastfeeding
What symptoms are associated with HIV?
Initially a brief flu-like illness with swollen lymph nodes
Then range of symptoms
What is a prevention method for HIV?
Using condoms
Avoid contact with people’s blood
What is the treatment for HIV?
Antiviral drugs can slow actions of virus.
What microbe causes tuberculosis?
Bacteria
What is the transmission method for tuberculosis?
Infected person coughing or sneezing.
What symptoms are associated with tuberculosis?
Coughing, and coughing up blood
Difficulty breathing
What is a prevention method for tuberculosis?
BCG vaccine
What is the treatment for tuberculosis?
Combination of antibiotics
What microbe causes ringworm?
Fungus
What is the transmission method for ringworm?
Skin contact and sharing towels and bedding with infected person,
Cats and dogs
What symptoms are associated with ringworm?
Ring shaped pattern on skin
What is a prevention method for ringworm?
Avoid skin to skin contact and sharing towels and bedding with infected person
What is the treatment method for ringworm?
Antifungal medication
Good hygiene measures
What do microorganisms need to reproduce?
nutrients, warmth and water
What was the jelly bacteria grow on called?
Agar
What is a colony of bacteria?
Where initially just 1 bacterium was present a colony will grow. A colony will probably contain more than 1 million bacteria.
A step by step method on how to grow bacteria colonies?
- Keep the lid on one agar plate and seal it with masking tape. Label it control.
- Take the lid off the other agar plate and expose it to the air for 10 minutes. Put the lid back on and seal it with masking tape. Label the plate appropriately.
- Incubate the 2 plates at 25ºC for several days.
- Following incubation, observe the 2 plates (with the lids on and sealed!), and count how many colonies of bacteria have grown on the 2 separate plates and compare the results.
How can you tell how much bacteria is on the agar plate?
By counting the number of colonies
What are some safety precautions when growing bacteria?
- Do not touch, cough, sneeze or breathe on the agar plate when it is exposed to air.
- Do not remove the lids of the agar plates after they have been incubated.
What is non-specific immunity?
- It is present all the time
- It is not activated in response to a particular pathogen
How do eyes contribute to non-specific immunity?
*Tears wash out pathogens
*Enzymes in tears can kill pathogens
How does the nose contribute to non-specific immunity?
*Mucus traps pathogens, which are then swallowed or blown out in coughs and sneezes
How does the mouth contribute to non-specific immunity?
*Friendly bacteria help to prevent growth of harmful pathogens
*Saliva cleans and removes bacteria
How do the lungs contribute to non-specific immunity?
*Mucus traps bacteria and fungal spores
*Tiny hairs, called cilia, move the mucus to back of throat where it is swallowed
How does the stomach contribute to non-specific immunity?
*Acid helps to sterilise food
How does the intestine contribute to non-specific immunity?
*Friendly bacteria help to stop growth of harmful pathogens.
* Faeces contain over 30% live bacteria
How does the reproductive system to non-specific immunity?
*Slightly acid conditions in vagina and urethra help to stop the growth of pathogens
How does the skin contribute to non-specific immunity?
*Outer layer of skin is dead, which means it is a difficult environment for pathogens to grow on
*Cuts are the only way that pathogens can get through skin
What cells are involved in active immunity?
White blood cells (Lymphocytes and Phagocytes)
How does your body recognise a pathogen?
Its unique antigens
What are antigens?
protein molecules on the surface of every cell (including our body cells) that give it a unique set of characteristics.
Why does our body not attack our own cells?
It recognises our own antigens as being different.
What do lymphocytes do?
*Lymphocytes make specific antibodies that match the shape of the antigens on the surface of pathogens.
*Your body will keep a memory of how to make the antibodies, incase it encounters the same pathogen again. That is why we do not usually get sick from the same pathogen twice
How do phagocytes work?
Engulf and digest
Known as phagocytosis
What is meant by the term allergy?
Adverse reaction that body has to a particular substance.
Why might allergies be on the rise?
Pollution OR
The result of us living in a cleaner, germ-free environment (this reduces the number of germs our immune system has to deal with and so it overreacts when it comes in contact with harmless substances)
What is the name of the substance that triggers an allergic reaction?
Allergen
What are some good examples of allergens?
- Pollen
- Dust mites
- Nuts
What system in our body does an allergen trigger wrongly?
Our immune system
What is the name of the antibody that our immune system releases in response to the allergen?
Immunoglobulin E (IgE)
What does the antibody cause other cells to release, which helps to produce the symptoms of an allergic reaction?
Histamine
What are some of the symptoms of allergic reactions?
Sneezing and wheezing/ Runny nose /Rash / Swelling /Itchy eyes / Vomiting and diarrhoea
Who discovered vaccines?
Edward Jenner
How did Jenner come up with they idea of vaccines?
He had heard that people such as milkmaids who got cowpox (a mild infection), never suffered from smallpox (a deadly infection
How did Edward Jenner develop vaccines?
- He scratched pus from the blister of a milkmaid infected with cowpox onto the arm of a small boy called James Phipps. The boy became infected with cowpox.
- A few weeks later Jenner repeated the process with the same boy but used the smallpox virus instead. Fortunately, the boy did not get smallpox and the process of vaccination was developed.
Why did James Phipps not catch small pox?
The antigens of the cowpox and smallpox viruses were so similar.
Why do we usually not get sick with the same pathogen twice?
*After infection, the body keeps a memory of how to make the antibodies.
*Therefore, if the same pathogen enters the body again, the body will produce a greater number of antibodies and in a much quicker time compared with that of the first exposure.
*Therefore, the body is able to fight off the pathogen immediately, before the person has the symptoms of being sick.
what happens an enzyme if the temperature is too high?
Denatures - it won’t work
How is food used in the body?
The energy is released from the food in our body cells by a process called respiration.
What is the energy released by food used for? (4)
- Growth and repair
- Heat
- Movement
- Protection against disease
What are the seven food groups?
Carbohydrates, fats, proteins, fibre, water, minerals and vitamins
What is the main function of carbohydrates?
- Used as main source of energy.
What is the main function of fats?
- Used for food storage and insulation.
- It will be used for energy when the body uses up its carbohydrate stores
What is the main function of protein?
- Used for growth and repair of cells tissues and organs
What is the main function of fibre?
- This keeps the contents of the gut moving (prevents constipation).
- It also reduces the chances of bowel cancer.
What is the main function of water?
- It allows chemical reactions to occur, keeps you cool and transports wastes etc.
What is the main function of minerals?
- Help body to function properly. 16 different minerals are known to be needed in our diets.
What is the main function of vitamins?
- Help body to function properly and help keep the body healthy.
What are the two types of carbohydrates?
Sugar and starch
What foods can carbohydrates be found in?
Sugars are found in; fruit and sweets
Starch is found in; bread, rice, pasta
What foods can fats be found in?
dairy produce and red meat
What foods can protein be found in?
fish, chicken, beans and nuts
What foods can fibre be found in?
wholegrain products, brown rice, fruit and vegetables.
What foods can water be found in?
drinks, fruit and vegetables
What foods can minerals be found in?
mineral calcium is found in dairy produce and iron in found in red meat.
What foods can vitamins be found in?
fruit and vegetables
Balanced diet definition
a diet that contains all the 7 food groups in the correct quantities.
Malnutrition definition
A diet that contains enough food, but doesn’t contain the 7 food groups in the correct quantities
Starvation definition
When a person doesn’t have enough food to provide their body with its needs.
What is the chemical test for starch?
Iodine
What is the chemical test for protein?
Biuret reagent
What is the chemical test for fats?
Ethanol and water
What is the chemical test for sugar?
Benedicts reagent
What is a positive colour change for starch test (iodine)?
Orange/brown → blue/black
What is the chemical test for vitamin c?
DC PIP
What is a positive colour change for sugar test (benedicts)?
Blue → green → orange → brick red
What is a positive colour change for fats test?
Colourless → white emulsion
What is a positive colour change for protein test (biuret)?
Blue → purple
What is a positive colour change for Vitamic test (DC PIP)?
Blue → colourless
What is the method for Vitamin c test?
Add drops OF food sample TO DCPIP solution.
Definition of Digestion
The breakdown of large insoluble food molecules into small, soluble ones, so they can be absorbed into the blood
What is the function of the mouth in digestion?
This is where digestion of food starts – food is broken down by teeth and enzymes in saliva
What is the function of the oesphagus in digestion?
long tube that food passes down from mouth to stomach
What is the function of the stomach in digestion?
This is a muscular sac where digestion continues - food is broken down by enzymes in gastric juice.
Hydrochloric acid kills bacteria in food.
What is the function of the small intestine in digestion?
This is where digestion is completed - food is broken down by enzymes in pancreatic juice and fats are broken down by bile
This is also where absorption occurs – following digestion, the food molecules are now small enough to be absorbed from the digestive system into the blood, where they then travel to different parts of body for use.
What is the function of the large intestine in digestion?
Reabsorb water. All that is left in the digestive system after absorption is waste – this forms the faeces.
What is the function of the rectum in digestion?
This is where faeces are stored.
What is the function of the anus in digestion?
Faeces pass out of the body through the anus.
What is in gastric juice?
enzymes to break down food
What is the function of hydrochloric acid in the stomach?
Kill bacteria in food
What are fats broken down by in the digestive system?
Bile
Where is bile sent from, and where is it sent to?
Sent from liver
sent to small intestine
What is an enzyme?
Enzymes are proteins and are biological catalysts
What are two things that can affect how well an enzyme works?
pH and temperature
What is it known as when an enzyme works there best?
optimum
The heart is made from what type of muscle?
Cardiac
How is the cardiac muscle different from other muscles?
It does not get tired
What is the purpose of valves?
Stops blood from flowing backwards
Why is the left side of the heart thicker than the right?
The left side has to pump blood further and under more pressure to the body
