Chemicals of Life Flashcards
The human body consists of which substances? Name 3.
Carbohydrates
Proteins
Fibre
Water
Vitamins
Minerals
A _________ consists of daily-recommended intake of __________,__________,________,_________,_________,__________ and ________, together with an adequate amount of ____________.
balanced diet
carbohydrates, fats, proteins, vitamins, mineral ions and dietary fibre. water
Nutrients are sorted into:
Organic nutrients
Inorganic Nutrients
Food energy values are measured in:
Calories or joules
1 kilocalorie =
4.2 kJ
A carbohydrate is an organic substance containing what and in which ratio?
Carbon, Hydrogen and oxygen in the ratio 1:2:1
What types of carbohydrates are there?
Monosaccharide with one ring
Disaccharide which has 2 monosaccharide rings
Polysaccharides made of many monosaccharides joined together
Monosaccharides and disaccharides are all _______ sugars.
Soluble
All monosaccharides, most disaccharides and some polysaccharides are also ________sugars.
reducing
Name 3 sources of Carbohydrates
Pasta
Rice
Bread
Potatoes
Cereal
Milk/ dairy products
Fruits
Breakfast
Name the 3 functions of carbohydrates
as an energy supply
to build cell and body structures
to build other organic substance
How much kJ/g of energy do carbohydrates produce?
17
Can humans digest cellulose?
No, it ends up as fibre.
Why is dietary fibre important?
To produce bulk needed to eliminate feaces and helps food move easily in the intestines.
Lipids are an organic substance containing?
Carbon, Hydrogen and Oxygen
What is a lipid molecule made up of?
1 glycerol and 3 fatty acid molecules
Lipids are divided into 2 types, which are?
Saturated and unsaturated fats
Fats can be obtained mostly from what?
Butter
Fish
Nuts and seeds
Name the functions of lipids
As an energy supply
to store vitamins
to build cell structures
for protection
to provide heat insulation
for waterproofing
A protein contains what (elements)?
carbon hydrogen oxygen and nitrogen, sometimes even phosphorus and sulphur
How many amino acids are there?
20, 8 of which are essential
Amino acids can be joined together using what? And what is the long chain form called?
peptide bonds
polypeptide bonds
How do these chains join together?
using cross linkages
Name 5 foods proteins are abundant in.
Egg white
Meat
Poultry
Beans
Nuts
Dairy
Name the main functions of proteins
To supply energy
to build up structures
as enzymes
for growth and repairing
to work as hormones
How much kJ/g of energy is produced during respiration?
18
Proteins also allow?
Movement
Enzymes. What do these act as?
catalysts
Name a hormone in the human body.
adrenaline
testosterone, insulin and more
Are vitamins a source of energy?
No
Vitamins are needed only in ____ _____ __________.
very small quantities
Vitamins can be divided into:
Water-soluble vitamins
Fat-soluble vitamins
Which type of vitamin is able to be stored in the body? Where do we get such vitamins?
Fat-soluble vitamins which can be obtained mainly from animal fats and vegetable oil.
What happens when too much protein is consumed?
Excess protein is de-aminated (broken down) in the liver and excreted with urine.
Can plants make their own vitamins?
Yes
Mention 2 types of vitamin A and state whether they’re water-soluble or fat-soluble
Retinol (fat-soluble)
Carotene (water-soluble)
Mention a type of vitamin C and state whether it’s water-soluble or fat-soluble.
Ascorbic acid (water-soluble)
Mention a type of vitamin D and state whether it’s water-soluble or fat-soluble.
Calciferol (fat-soluble)
From which sources can we get vitamin A?
Retinol - Fish liver oil
Dairy products
Eggs
Chicken
Liver
Carotene - Orange, yellow and green vegetables and fruits
Carrots, spinach, apricots, oranges etc…
From which sources can we get vitamin C?
Ascorbic acid - All citrus fruits
Kiwi
Strawberries
Broccoli
Red peppers
Tomatoes
Cauliflower
Parsley
From which sources can we get vitamin D?
Calciferol - Fish liver oil
Dairy products
Eggs
Oily fish
Liver
What happens to vitamin C when heated?
It’s destroyed
Why is Retinol important?
It’s important for the retina to function properly.
Carotine is turned into ____ by the body.
Carotine is turned into Retinol by the body.
Some associated deficiencies symtoms to lack of vitamin A.
- Reduced resistance to desease.
- Retarded growth
- Unhealthy hair and skin
- Poor night vision
- Cornea of eyes becomes dry and opaque, leading to xerophtalmia or blindness
xerophtalmia isn’t mportant for the exam
Some associated deficiencies symtoms to lack of vitamin C.
- Reduced resistance to diseases
- Scurvy
- Poor healing of wounds
What is Scurvy?
A disease causing bleeding in various body parts, particularly gums and around bones. Scury is only likely to occur when fresh food isn’t available.
Some associated deficiencies symtoms to lack of vitamin D.
- Retarded growth
- Calcium isn’t deposited properly in the bones, causing
1. Rickets in children
2. Osteomalacia in adults
What happens if you consume too much vitamin D?
Can cause tissues like the lungs and kidney to become calcified.
What is Rickets?
Bones remain soft so they end up deformed by child’s weight.
Where is most of the water in our body?
In the cytoplasm of the cells or in the tissue fluid between the cells.
What is the importance of water in organisms?
- As a reactant (in digestion, water is involved in a process called hydolysis to convert insoluble substances into soluble ones)
- As a medium for chemical reactions in solution
- Transport of substances in solution
Where are minerals obtained from?
The environment
2 important minerals in plants and their functions in plants
- Nitrogen: Synthesis of proteins and other complex substances
- Magnesium: To make uo chlorophyll, needed to trap light for photosynthesis.
Important minerals in humans
- Calcium
- Iron
- Phosphorous
What is Anemia?
Lack of iron in the body
What happens if not enough calcium is eaten?
The body takes calcium needed from the bones.
What is metabolism?
Is the term referring to all the chemical reactions taking place in a living thing.
What is an enzyme?
They’re protein that act as biological catalysts because they speed up chemical reactions taking place inside cells.
Charateristics of enzymes
- Always proteins
- Specific in their action
- Can be used over and over again
- Sensitive to pH
- Sensitive to heat
Enzymes are involved into 2 types of metabolic reactions:
- Build-up (anabolic) reactions
- Break-down (catabolic) reactions
