B1.1 Keeping Healthy NOT FINISHED Flashcards
What are the 5 important nutrients?
Carbs, proteins, fats, vitamins, and mineral ions
What do you need carbs?
To release energy
Why do you need fats? (2)
To keep warm and release energy
Why do you need proteins? (3)
Growth, cell repair and cell replacement
Why do you need vitamins and mineral ions? (4)
To keep your skin, bones, blood, and everything else generally healthy
What is another key nutrient? Why do you need this?
Fibre, it helps to keep everything moving smoothly through your digestive system
What are sources of carbs? (2)
Pasta, rice
What are sources of fats? (2)
Butter, oily fish
What are sources of proteins? (2)
Meat, fish
What are sources of vitamins? (2)
Vitamin C in oranges and vitamin D in eggs
What are sources of minerals? (2)
Calcium in milk, and iron in red meat
What are the reactions called in your body that keep you alive?
Your metabolism
What is the speed at which your metabolism occurs called?
Your metabolic rate
What increases your metabolic rate? (4)
The more muscle you have in your body (muscle needs more energy than fat), the bigger you are, men have faster metabolic rates than women and regular exercise can boost your resting metabolic rate
When is your metabolic rate highest? Why?
During and after exercise, as you need more energy when exercising
What determines how much energy you should have in order to stay healthy?
If you do little exercise (or any other activity), you will need less energy, and vice versa
What are people called which have a diet that is badly out of balanced?
Malnourished
What can eating too much carbs and fats lead to?
Obesity
What classifies someone as obese?
When they are 20%< over their recommended body mass
What can cause obesity? (2)
Overeating and a lack of exercise, or hormonal problems
What can obesity lead to? (4)
Arthritis, type 2 diabetes, high blood pressure, and heart disease
What can too much saturated in your diet cause?
An increase in your blood cholesterol level
What can eating too much salt lead to? (2)
High blood pressure and heart disease
What are the common symptoms of eating too little? (5)
Slow growth, fatigue, poor resistance to infection, and irregular periods in women
Why is exercise good for health? (3)
Because it increases the amount of energy used by the body and decreases the amount stored as fat and it also increases your metabolic rate as it helps to build muscle
Can you bit fit, but not healthy?
Yes, you can be physically fit but at the same time, your diet could be unbalanced
What inherited factors can affect your health? (2)
You can inherit factors that affect your metabolic rate. e.g. an underactive thyroid gland causing your MR to slow down, and you can inherit factors that affect your blood cholesterol level - too much cholesterol can lead to heart disease
What makes a food unhealthy? (3)
A high saturated fat content, a high sodium or salt content, and a high energy content
What makes a food healthy? (5)
The opposite of unhealthy foods, but is also high in protein, fibre, minerals and vitamins
What factors do you need to consider when evaluating slimming claims?
Is the report a scientific study, published in a reputable journal?
Was it written by a qualified person who is not linked to the people selling it? (so it is not biased)
Was the sample of people asked/tested large enough?
Have there been other studies which found similar results?
Diet and slimming products will only work if… (2)
You eat less fat or carbs, or you exercise more
What are microorganisms called that cause disease?
Pathogens
What do pathogens cause?
Infectious disease - diseases that can easily spread
What are the two main types of pathogens?
Bacteria and viruses
How do bacteria make you feel ill? (2)
By producing toxins, and by damaging cells
Are viruses cells?
No
How do viruses replicate themselves?
They invade your cells and use the cells’ machinery to produce copies of themselves
How do viruses make you feel ill?
As viruses replicate themselves within cells, it reaches a point where the cell can no longer hold anymore viruses so the cell bursts - this damaging of the cell makes you feel ill
What is an example of a virus?
HIV
What are the body’s defences? (2)
The skin and mucus in the respiratory tract
Why is the skin a form of defence?
Because it stops pathogens from getting inside your body
What happens if you get a cut, so pathogens can now enter your body?
Platelets (small fragments of cells), help blood to clot quickly to seal wounds
How does the mucus in the respiratory tract prevent pathogens from entering the body?
Sticky mucus lines the respiratory tract, this traps pathogens in the air and stops them from reaching the lungs
How are the pathogens removed from the mucus in the respiratory tract?
Tiny hairs in the tract beat to move the mucus away from the lungs and towards the mouth where you can spit it out
What happens if pathogens make it through your defences?
The immune system kicks in
What is the most important cell of the immune system?
The white blood cell
How do white blood cells consume pathogens?
WBC can engulf pathogens and digest them
Why do white blood cells produce antitoxins?
They counteract toxins produced by invading bacteria
What is unique about invading cells?
A molecule called antigens on its surface
What happens when a white blood cell comes across a foreign antigen?
It produces proteins called antibodies, which lock onto the foreign antigens and kill the invading pathogen
What determines the antibodies produced by a WBC?
They are specific to that type of antigen
What happens when a WBC produces the antibodies for a specific antigen?
Antibodies are produced rapidly and carried around the body to kill all similar bacteria or viruses
How do people become immune to a pathogen?
If a person becomes infected with a pathogen which they have already overcome, the WBC can easily produce the antibodies to kill it
What are vaccinations?
Substances that prevent you from getting ill from a microorganism in the first place
How do vaccinations work?
Small amounts of dead/inactive microorganisms are inserted into the body which carry antigens allowing the WBC to produce antibodies to attack them (even though they are harmless) and thus make the person immune
What is an example of a vaccine?
The MMR vaccine which is given to children and is a vaccine for measles, mumps and rubella
What are the pros of vaccines? (2)
They have helped to control lots of infectious diseases e.g. smallpox which was once very common, and they can prevent epidemics as long as a large percentage of the population is vaccinated
What is an epidemic?
A big outbreak of a disease
What are the cons of vaccines? (2)
They don’t always work, and you can have bad reactions to the vaccine e.g. swelling or fevers
What do you need to do when thinking about having a vaccine?
You need to balance the risks
What are the two different types of drugs?
Painkillers and antibiotics
What are painkillers?
Drugs that relieve pain, they don’t tackle the cause of the disease, they help to reduce the symptoms
What is an example of a painkiller?
Aspirin
What are antibiotics?
Drugs that kill/prevent the growth of bacteria without harming body cells
What is an example of an antibiotic?
Penicillin
Do antibiotics destroy viruses?
No
Why is it difficult to produce drugs which destroy viruses?
Because they reproduce in cells, so it is hard to destroy viruses without harming body cells
What is a mutation?
A change in genetic material
How does antibiotic resistance develop?
An infection can be caused by bacteria which are, and aren’t resistant to antibiotics - so when you take antibiotics, only the non-resistant bacterium are killed, and the resistance bacterium can reproduce
Why have resistant strains of bacteria increased?
Due to natural selection
What are two examples of resistant strains of bacteria?
MRSA and TB
How can the development of antibiotic resistance be slowed down?
To slow it down, it is important not to over-use antibiotics
How can you test the action of antibiotics/disinfectants?
By growing cultures of microorganisms
What does agar jelly contain? Why?
It contains the vital components which are needed to grow e.g. carbohydrates
How are unwanted microorganisms killed which are found on agar jelly?
The agar jelly is heated to kill off any unwanted microorganisms
How are inoculating loops sterilised before use?
They are passed through a flame
How are microorganisms prevented from contaminating the culture of microorganisms?
A lid is taped on the petri dish
How does the temperature of the culture of microorganisms vary depending where they are grown? (2) And why?
In schools they are grown at around 25°C because harmful pathogens aren’t likely to grow at this temperature, but in industrial conditions, the temp. is much higher so they grow a lot faster
What did Dr Ignaz Semmelweis discover?
That in the hospital he was working in, there were lots of women who were dying after birth due to a disease called puerperal fever - he then told his doctors to wash their hands between patients to prevent the spreading of the disease and it worked
Why was Semmelweis’ discovery rejected?
Because bacteria had not yet been discovered so he couldn’t prove why his idea worked
What can antibiotic-resistant bacteria cause? Why?
They can cause an epidemic because the rapid spread of the disease would be difficult to treat
What is an epidemic?
A big outbreak of disease
Can viruses mutate?
Yes
What can a mutation of a virus result in?
A virus that is both deadly and very infectious
What is a pandemic?
When a disease spreads all over the word
Why do pandemics occur?
Because people are constantly moving from one country to another e.g. by plane
