Ch.5 Food and humans Flashcards
Food provides us with:
- _______ for supporting daily activities and keeping us warm
- raw materials for _______ and _______ of body tissues
- substances that are important for maintaining _______
energy;
growth; repair;
health
T/F: Food contains six types of food substances that are essential to health.
F
Food contains seven types of food substances that are essential to health.
a) Water b) Proteins c) Carbohydrates
d) Vitamins e) Lipids f) Minerals
g) Dietary fibre
Provides energy: _________
Does not provide energy: _________
Provides energy: b, c, e
Does not provide energy: a, d, f, g
Carbohydrates:
- _____saccharides (單糖)
- _____saccharides (雙糖)
- _____saccharides (多糖)
monosaccharides;
disaccharides;
polysaccharides
Functions of carbohydrates:
- sugars and s_______ act as the main energy source
- g_________ acts as energy reserves
- c_________ is a source of dietary fibre
starch (澱粉) ;
glycogen (糖原) ;
cellulose (纖維素)
Food sources:
_______ - fruits, honey, milk, and table sugar
_______ - rice, wheat, potatoes ang taros
sugars;
starch
The commonest type of lipids, ____________, are formed from the condensation of one glycerol and three fatty acids.
triglycerides (甘油三酯)
Functions of lipids: (1/2)
- act as energy _________
- fat in adipose tissues around the internal organs acts as a ______ _________
- subcutaneous fat acts as a _____ insulator
reserves;
shock absorber;
heat
Functions of lipids: (2/2)
- they are involved in the absorption, transport and storage of lipid-soluble ________
- they are used to produce some _________
- ____________ are the major components of cell membrane
vitamins;
hormones;
phospholipids
Food sources of _______ include fatty meat, seeds, nuts, milk and dairy products.
lipids
Proteins consist of one or more ____________, which are formed form the condensation of amino acids.
polypeptides (多肽)
Functions of proteins:
- used for ________ and _______ of body tissues
- used to produce e_______, antibodies, haemoglobin and some hormones
- broken down to release _______ if carbohydrates and fat stored are used up
growth; repair;
enzymes;
energy
Food sources of _________ includes meat, fish, eggs, beans, milk and dairy products.
proteins
Name two minerals which are essential for humans.
Calcium / Iron
Functions of calcium:
- a component of ______ and ______
- involved in blood _______, muscle __________ and sending messages in the _______ system
bones; teeth;
clotting; contraction; nervous
Deficiency of calcium may cause _______ in children.
rickets (軟骨病)
Food sources of ________ include canned sardines, milk, dairy products, tofu and some green vegetables
calcium
Iron is a component of ____________.
haemoglobin
Deficiency of iron may cause ________.
anaemia (貧血)
Food sources of _____ includes beef, liver, beans, cabbage, spinach and raisins.
iron
Vitamin A and D are _____-soluble while vitamin C is ______-soluble.
lipid; water
Functions of vitamin A:
- needed for the formation of a _______ in the retina
- keeps the _______, skin, _______ of the alimentary canal and _________ system healthy
pigment;
cornea; linings; breathing
Deficiency of vitamin A may cause:
- n______ b__________
- drying up of the _______ and skin
- easy infection of the lining of the ______ and trachea
night blindness;
cornea;
lungs
Food source of vitamin A:
- _____ _____ oils, liver, eggs, milk and dairy products
- vegetables and fruits containing __________ (e.g. carrots, pumpkin, sweet potatoes and mangoes)
fish liver;
carotene (胡蘿蔔素)
Vitamin D promotes the absorption of ________ and phosphate.
calcium
Deficiency of vitamin D may cause _______ in children.
rickets
Food sources of vitamin ___:
- fatty fish, fish liver oils, liver and egg yolks
- produced by the skin under sunlight
D
Function of vitamin C:
- needed for the _______ and ______ of connective tissues
- promotes the absorption of _____
- helps the _______ system work properly
growth; repair;
iron;
immune
Deficiency of vitamin C may cause _______.
scurvy (壞血病)
Food sources of vitamin __ include fresh vegetables and fruits.
C
Dietary fibre helps faeces pass out of the body by adding bulk to food to stimulate _________ along the gut and holding ______ to make faeces softer.
peristalsis (蠕動) ; water
Deficiency of dietary fibre may cause __________.
constipation (便秘)
Food sources of _______ _____ include vegetables, fruits and wholemeal (全麥) products.
dietary fibre
Functions of water in the body:
- as a _________
- as a medium for c________ r________
- as a medium for t_______
- as a c_______ agent to help regulate body temperature
- as a major component of l________ fluids
reactant; chemical reactions; transport; cooling; lubricating
Food test of glucose - using a glucose test paper: dip the test end into the food sample)
Positive result: _______ of the test end changes
colour
What is the food test of reducing sugars (monosaccharides and disaccharides except sucrose)?
Benedict’s test
In Benedict’s test, we add an equal volume of Benedict’s solution to the food template and ____ the mixture in a water bath for 5 minutes.
boil
Positive result of _________ test: a brick-red precipitate(沉澱物) is formed. It proofs the presence of reducing sugar.
Benedict’s
We use grease spot test (油漬試驗) to identify the presence of _______.
lipids
In grease spot test, we put a drop of the food sample onto a piece of ______ paper. We observe whether there is a translucent spot after drying. Then we immerse the spot onto an organic ________ and see if the spot disappears.
filter; solvent
Positive result of _______ _____ test: a translucent spot is formed, which disappears after it is immersed into an organic solvent. It proofs the presence of _______.
lipids
Food test of proteins - using a protein test paper: dip the test end into the blood sample.
Positive result: _______ of the test end changes
colour
Food test of vitamin __ - DCPIP test: add the food sample to DCPIP solution drop by drop with gentle shaking
Positive result: DCPIP solution ___________
C;
decolourizes (褪色)
A balanced diet consists of all the food substances in the right _________ and _____________.
amount; proportion
We should maintain a balance between the energy ______ and energy _______ to stay healthy.
input; output
There many factors affecting our dietary requirements. For instance, ____, ____, level of __________ and body status.
age; sex; activity
Children require the greatest amount of energy per unit body mass. They have the highest _________ rate, growth rate and rate of heat loss.
metabolic
Children and teenagers need large amounts of ________, ________ and iron. They are growing actively. These nutrients are needed for building body tissues.
proteins; calcium
Males need more energy than females. They have a higher _________ rate, higher rate of heat loss, larger body _____, and more muscular.
metabolic; size
Males need more proteins than females. Proteins are needed to build and repair ________.
muscles
Females need more iron than males. Iron is needed to replace the loss of iron during ____________.
menstruation (月經)
People who are more physically active need more energy. Energy is needed for _________ activities.
muscular
Pregnant women need more energy, proteins and iron. Energy and protein are needed for _______ of the foetus. Iron is needed for the formation of foetal ____ ______ cells.
growth; red blood
Breast-feeding mothers need an extra supply of various types of nutrients. These nutrients are needed for _____ production.
milk
Eating too little implies energy input is { more / less ) than energy output. The body breaks down food ________, resulting in weight loss.
reserves
Eating too much implies energy input is ( more / less ) than energy output, resulting in weight gain.
more
A person is __________ when the body weight exceeds normal levels. In serious cases, it becomes ________.
overweight; obesity
People who are overweight or obese have a higher risk of a number of diseases. Give examples.
Diabetes mellitus / high blood pressure / heart disease / stroke (中風) / arthritis (關節炎)
N________ l______ provide information about the energy and nutrient contents of food.
Nutrition labels
