Molecules, DNA and Kingdoms Flashcards
What are proteins made of?
Amino Acids
How many Amino Acids are there?
20 - Can be put in any order resulting in millions of different combinations
Why does the shape of a protein matter?
It helps carry out its job.
How to Test for Glucose?
Benedict’s solution - Add benedict’s solution to sample of food (solution), place in hot water bath (80 degrees Celsius) for 5 minutes;
If solution is red then high concentration of sugar. If Green, yellow or orange then still positive but less concentration than red.
How to test for Starch?
Iodine solution - Add a few drops of solution on a spotting tile. If starch is present then blue-black colour will show.
How to test for protein?
Biuret - Add 2cm cubed of water to sample and shake (If not already liquid). Add an equal volume of dilute potassium hydroxide and shake. Add 2 drops of 1% copper sulphate solution. If protein is present then pale purple colour will develop.
How to test for lipids?
Emulsion - Food sample placed on test tube. Add small volume of absolute ethanol and shake to dissolve and lipid in the alcohol. Add an equal volume of water. A cloudy white colour indicates the presence of lipids.
What is a chromosome?
A strand of DNA. Most cells contain pairs of chromosomes, both with the same genes.
What is a gene?
A short section of DNA within a chromosome. It codes for a specific protein which gives us characteristics.
What is a genome?
The total DNA for an organism - coding for all its characteristics.
What are the four bases?
Adenine pairs with Thymine
Cytosine pairs with Guanine
How is a nucleotide formed?
Nucleotide is formed of a sugar, a phosphate and nitrogenous base
What shape does The DNA take?
A Double Helix
What smaller units make carbohydrates?
Carbon, hydrogen and oxygen
What smaller units make lipids?
Carbon, hydrogen and oxygen
What smaller units make protein?
Carbon, oxygen, hydrogen and nitrogen
What smaller units make DNA?
Nucleotides
