Biology Chapter 1 - Food and Diet Flashcards
What are carbohydrates needed for
Energy
What foods are high in starch
Bread, pasta, rice
What foods are high in sugar
Cake, biscuits
What is the test for sugar
Add benedicts
Heat in a water bath
Turns blue to brick red precipitate
What is the test for starch
Add iodine
Turns yellow brown to blue black
What are proteins needed for
Give 2 foods high in protein
Growth and repair
Eggs, milk, meat, fish
What is the test for protein
Add biuret reagent (or sodium hydroxide and copper sulfate)
Turns blue to purple
What is fat needed for
Insulation and energy store
What is the test for fat
Add ethanol and shake. then add equal amount of water
Cloudy white emulsion if fat is present
What is the equation for respiration
Glucose + Oxygen —–>Carbon dixoide + Water + Energy
Higher tier
C6H12O6 + 6H2O —–> 6CO2 + 6H2O
What is respiration
Process of releasing energy from food
What type of reaction is respiration
Exothermic
What factors affect how much energy you require
Age - older people need less energy
Gender - males need more than female
How active you are - more active need more energy
How can you test foods to see which has most energy
Place volume of water (20cm3) in boiling tube and clamp
Add thermometer and record initial temperature
Record mass of food to be burnt
Light food in bunsen flame and place under boiling tube
Let burn completely and record final temperature
What are the 2 types of circulatory diseases
Heart disease
Stroke
How does coronary heart disease cause a heart attack
cholesterol blocks the coronary arteries (supplying heart muscle)
Less oxygen and glucose to muscle cells of heart
Less respiration
Heart muscle cells die
What is a stroke
A blockage in artery in brain - less food and oxygen to cells in that part of brain - less respiration - those cells in that part of brain die
What lifestyle factors can you do to reduce risk of heart disease or stroke
Less stress
More exercise
Stop smoking
What dietary factors can you do to reduce risk of heart disease or stroke
Less saturated fat intake
Less salt intake
Less cholesterol intake
Why are circulatory diseases an economic problem
Cost of treatment - medicines required
Need trained staff to look after patients
more people in hospital longer time
How does exercise affect pulse rate - how does fit person compare to less fit person
Pulse rate increases -
more fit will have lower resting pulse rate than less fit person
more fit will have lower maximum pulse rate
more fit will recover quicker - pulse rate back to normal
What is meant by recovery time
The time it takes for the heart rate to return to normal after exercise
What are the benefits of exercise
Strengthens heart muscle
This increases cardiac output - the amount of blood pumped out of heart per minute
this causes the pulse rate than to lower as heart has to pump less often
