Unit 2: Section 4 - Diet and Food Production Flashcards
7 components of a balanced diet
Carbohydrates Proteins Fats Vitamins Minerals Fibre Water
what is the role of carbohydrates?
To provide energy
what is the role of proteins?
Growth and repair, also provide us with essential amino acids
what is the role of fats?
Energy store, insulation, provide essential fatty acids
what is the role of vitamins?
Needed for different functions e.g. vitamin D is needed for calcium absorption. Also some vitamins are used to make coenzymes
what is the role of minerals?
Different minerals have different functions, e.g. iron is needed to make haemoglobin. Also some minerals are cofactors
What is the role of water?
Needed to replace fluid loss through urine, sweating. Also has many roles in the body, e.g. solvent, coolant
what is the role of fibre?
Aids movement of food through gut, reduces chances of bowel cancer and heart disease.
What is malnutrition?
Having too much or too little of some nutrients in a diet.
How does an unbalanced diet lead to malnutrition?
Not enough of a nutrient can cause deficiency illnesses, e.g. not getting enough vitamin D can cause rickets.
Getting too much of a nutrient such as carbohydrates or fats can lead to obesity and other diseases such as CHD or type 2 diabetes.
What is hypertension?
When a persons salt intake is high it will lower the water potential of the blood, this means that more water is retained in the blood which increases blood volume. This leads to a strain being put on arteries in the brain, causing a stroke.
What is a lipoprotein?
A small particle made in the liver to transport cholesterol
Describe the structure of a lipoprotein
It is coated with protein to make it water soluble, and contains a core of cholesterol and other lipids
What are the two types of lipoproteins?
Low density lipoproteins (LDLs)
High density lipoproteins (HDLs)
What do HDLs do?
Remove cholesterol from the tissues and transport it to the liver
What do LDLs do?
Deliver cholesterol from the liver to the tissues
A diet high in HDLs will…
Mean that more cholesterol is transported out of the blood, decreasing the risk of CHD
A diet high in LDLs will…
Mean that more cholesterol is being transported into the blood, increasing the risk of CHD
What happens if an endothelial lining of an artery is damaged?
LDLs will deposit cholesterol which will accumulate along with fatty acids. This fatty material forms atheromus plaques inside the walls of the artery. Atherosclerosis is the progressive build up of plaque. Plaque thickens the walls giving the blood less space to flow through increasing blood pressure. It also roughens the lining of arteries, so increases the chance of blood clots forming
What are the symptoms of angina and why?
The aorta and coronary arteries provide the heart with oxygen, if these become blocked by plaques, the heart muscle will be deprived of oxygen and become fatigued. This means that people with the condition may find even mild exercise difficult and have chest pains after exercise.
How does a heart attack happen?
If a blood clot forms in a coronary artery it may reduce blood flow so much that the heart muscle dies, causing a heat attack.
What are the symptoms of angina and why?
The aorta and coronary arteries provide the heart with oxygen, if these become blocked by plaques, the heart muscle will be deprived of oxygen and become fatigued. This means that people with the condition may find even mild exercise difficult and have chest pains after exercise.
How does a heart attack happen?
If a blood clot forms in a coronary artery it may reduce blood flow so much that the heart muscle dies, causing a heat attack.
