B4. Biological molecules Flashcards
(18 cards)
What are the three main types of biological molecules important in living organisms?
Carbohydrates, proteins, and lipids (fats and oils).
What elements are found in carbohydrates?
Carbon (C), hydrogen (H), and oxygen (O).
Give an example of a monosaccharide.
Glucose (C₆H₁₂O₆).
What are disaccharides? Give one example.
Sugars made of two monosaccharide molecules joined together. Example: sucrose (table sugar).
What are polysaccharides? Give examples.
Large, complex carbohydrates made from many simple sugar units. Examples: starch, glycogen, cellulose.
What are the elements found in proteins?
Carbon (C), hydrogen (H), oxygen (O), nitrogen (N)
What are the basic building blocks of proteins?
Amino acids.
How are proteins formed from amino acids?
By linking amino acids together in a specific sequence
What are the elements found in lipids?
Carbon (C), hydrogen (H), and oxygen (O)
What are the basic units (building blocks) of lipids?
Fatty acids and glycerol.
What is the function of carbohydrates in organisms?
Main source of energy.
What is the function of proteins in organisms?
Growth and repair of tissues; enzymes; hormones; antibodies.
What is the function of lipids in organisms?
provide and store energy
Describe the test for starch.
Add iodine solution; if starch is present, the solution turns blue-black.
Describe the test for reducing sugars (like glucose).
Add Benedict’s solution to the food sample, heat the mixture in a water bath at about 80°C for a few minutes. if reducing sugars are present, the solution turns from blue to red.
Describe the test for proteins.
Add a few drops of Biuret solution to the food sample, If protein is present, the solution will change from blue to purple
Describe the test for lipids (emulsion test).
Mix the sample with ethanol, then add water; a milky-white emulsion indicates the presence of lipids.
What are enzymes made of?
Proteins.
