Biology Chapter 3.2 NOTES + BOOK + EXERCISES Flashcards
A balanced diet is just the right amount of different nutrients in our day to day meals
it is easy to store fats and carbohydrates. we must be careful of our fat intake. if we have extra energy from fats/carbohydrates, it will be stored- so we must make sure we eat just the right amount. We get all these nutrients from different sources and foods
what is meant by a ‘balanced diet’
a balanced diet is one in which energy giving foods (like carbohydrates and fats) in each meal are balanced by body building foods (proteins) and protective foods (vitamins and minerals)
a balanced meal is made up of at least one part of protein, no more than one part of fat and four parts of carbohydrate. it must also include foods such as salads which are rich in vitamins and minerals
why is it important for one day’s food to supply no more than one day’s energy
it is very important that the amount of food eaten each day should supply no more/less than the energy used that day. this is because if we regularly eat an amount of food which supplies more energy than we need, the surplus/extra food will be converted to fat and this could make us overweight.
Why is it dangerous to be overweight
People who are overweight (obese) have the risk of developing diseases of their heart and blood vessels. They are also more likely (than slim people) to have high blood pressure, diabetes, digestive disorders, etc. The more overweight we are, the more we endanger our life.
List some food which should be avoided by people who wish to lose weight. Which foods can they eat any amount of?
To make ourselves healthy and save our bodies from the risk of all these diseases
To reduce weight/stop becoming overweight, avoid sugar (cakes, pastries, biscuits) and fried and fatty foods.
This is because small amounts of these foods supply huge amounts of energy. Thus, we end up eating enough to satisfy our daily energy needs long before we satisfy our appetite.
However we can eat as much as we’d like of fresh fruits, salad, green and root vegetables, kidney, heart, cottage cheese, yoghurt and thin soups.
how many main factors are there that affect our balanced diet and what are they
There are 3 main factors that affect our balanced diet:
1. Age - (children are more active) we need to look after our diet according to our age
2. Gender - (males use up more energy in one day than females do)
3. Activities/occupation - (depending on how much energy we need to use according to our job
Fats provide ____ kJ of energy
Carbohydrates provide _____ kJ of energy. Carbohydrates get used up very quickly so we dont need to store the excess.
39, 17
describe how cholesterol is formed due to fats/the harmful effects
The main thing about fats is that eating too much of it can cause heart diseases. When it flows through our blood vessels and throughout or body, cholesterol (a type of fat) is deposited into that vessel. As a result, the blood vessel will get narrower and blood will not be able to flow through our body easily. If the blood cannot flow, the tissues around that vessel will not get enough oxygen.
We can get many diseases due to the blockage of blood vessels. We may get heart attacks, our blood may become thick, etc. These are caused by cholesterol.
Overall, eating too much fat causes a very bad toll/effect on our health.
