biomolecules Flashcards
What are biomolecules
-They are complex chemicals needed by organisms for metabolism, all the chemical reactions that happen in the body.
-Present in every organism
-Level of organization: Molecules
Explain Carbohydrates
-Contain C, H, O
-Units: Simple sugars (Glucose: Simple Sugar made in photosynthesis, used in respiration. 6 C atoms in a ring)
-Complex sugars(Surcose: Double-sugar molecule. 2 simple sugars joined by chemical bonds)
-Complex carbohydrates:
-Starch: Energy storage for plants. Enzymes to catalyse reactions that join glucose
-Glycogen: Made from glucose by animals. Energy storage
-Cellulose: Thousands of glucose units. Plants. Structure
Explain Proteins
-C, H, O, N, S
-Units: Amino Acids(20 types, made into chains, sequence determines protein)
-Functions: Structural, Defence, Transport, etc.
Fats
-C, H, O
-Units: 1 glycerol, 3 fatty acids
-Functions: Energy storage & thermal insulation
Nucleic Acids
-DNA: Deoxyribonucleic acid(chemical)
-C, H, O, N, P
-Unit: Nucleotide(phosphate group, sugar, base(Thymine, Adenine, Cytosine & Guanine))
-2 strands of nucleotides, make a double heliz
-Complementary base pairing: A pairs with T and C with G
Test for biomolecules
-Starch:
-Half test tube of food extract + 2-3 drops of iodine solution,
-Yellow/light brown = negative
-Blue/black = positive.
-Reducing Sugars:
-Food extract + same volume of Benedict’s solution into boiling water
-Bright blue = Negative
-(Green-yellow) orange-red = positive
-Proteins:
-Half test tube of extract + 5-6 drops of biuret solution
-Blue = Negative
-Violet, purple, lilac = Positive
-Fats:
-Grind food extract, add to test tube, cover with ethanol, shake, add distilled water until test tube is half full.
-Not cloudy white = Negative
-Cloudy white = positive
-Vitamin C:
-Put SCPIP in test tube and add extract through pipette or syringe 1 drop at a time
-Blue = negative
-DCPIP colour disappears = positive
