B3 Biological molecules: key vocabulary
Fourteen key words for IGCSE Co-ordinated Sciences topic B3 (biological molecules), with the Vietnamese meaning, how to say each word, a picture and an example. Ends with a test section, and a typing trainer on the site that also practises twelve general science words.
Practice
- B3 Biological molecules: vocabulary trainer – Practise 26 words by typing them: the 14 words of the unit and 12 general science words (compound, dissolve, reagent). Questions give a definition, a sound or an example sentence; words you miss come back, words you know come back later.
Transcript
Welcome. Here are fourteen key words for topic B three, biological molecules. Listen to each word. Read the Vietnamese meaning. Then look at the picture.
carbohydrate. carbohydrate. A carbohydrate is a molecule made of carbon, hydrogen and oxygen, such as sugar or starch. Here is an example. Bread and rice contain a lot of carbohydrate.
glucose. glucose. Glucose is a simple sugar. Starch and glycogen are built from it. Here is an example. Cells use glucose in respiration.
starch. starch. Starch is a carbohydrate made of many glucose molecules. Plants use it as a store. Here is an example. Potatoes store a lot of starch.
glycogen. glycogen. Glycogen is a carbohydrate made of many glucose molecules. Animals use it as a store. Here is an example. The liver stores glycogen.
protein. protein. A protein is a large molecule made of many amino acids joined in a chain. Here is an example. Meat, fish and eggs contain protein.
amino acid. amino acid. An amino acid is a small molecule. Many of them join to make a protein. Here is an example. Proteins are made of amino acids.
lipid. lipid. A lipid is a fat or an oil. It is made of fatty acids and glycerol. Here is an example. Butter and olive oil are lipids.
fatty acid. fatty acid. A fatty acid is a molecule that joins with glycerol to make a lipid. Here is an example. Three fatty acids join to one glycerol molecule.
glycerol. glycerol. Glycerol is a small molecule. It joins with fatty acids to make a lipid. Here is an example. A lipid contains one glycerol and three fatty acids.
D N A. D N A. D N A is the molecule that carries the instructions for building an organism. Here is an example. D N A is found in the nucleus of a cell.
double helix. double helix. A double helix is the shape of D N A: two strands twisted together. Here is an example. D N A has the shape of a double helix.
reducing sugar. reducing sugar. A reducing sugar is a sugar, such as glucose, that Benedict's solution can detect. Here is an example. Glucose is a reducing sugar.
Benedict's solution. Benedict's solution. Benedict's solution is a blue liquid that turns orange-red when heated with a reducing sugar. Here is an example. Add Benedict's solution and heat the tube.
iodine solution. iodine solution. Iodine solution is a brown liquid that turns blue-black when starch is present. Here is an example. Add iodine solution to test for starch.
Now, test yourself. I will show you a picture and the meaning in English. Say the English word out loud. Then listen, to check.
carbohydrate.
glucose.
starch.
glycogen.
protein.
amino acid.
lipid.
fatty acid.
glycerol.
D N A.
double helix.
reducing sugar.
Benedict's solution.
iodine solution.
element.
compound.
atom.
mixture.
dissolve.
solvent.
solution.
soluble.
insoluble.
precipitate.
reagent.
filter.
Fourteen words. carbohydrate. glucose. starch. glycogen. protein. amino acid. lipid. fatty acid. glycerol. D N A. double helix. reducing sugar. Benedict's solution. And iodine solution. Watch this video again until you know all of them.