B3 - Biological molecules Flashcards
Biological molecules (4)
Carbohydrates, lipids, proteins, nucleic acids
What is the function of biological molecules?
Aids organisms to grow, sustain, and reproduce
- they are involved in building organisms from single cells to complex living beings like humans, by interacting with each other
- the diversity in their shape and structure provides diversity in their functions.
Monomer
A simple compound whose molecules can join together to form polymers
- they are the building blocks to substances and make up the structure of biomolecules
What are carbohydrates?
Sugars and polymers of sugars (starches)
Carbohydrate monomer
- monosaccharide (glucose, fructose)
- disaccharide (maltose, sucrose)
- polysaccharide (starch, glycogen, cellulose)
What elements make up carbohydrates?
Carbon, Hydrogen, Oxygen, (CHO) 1:2:1 Ratio
What do carbohydrates (such as sugars) do?
An important source and release of energy (both short and long-term)
Give examples of carbohydrates (name 3)
bread, beans, milk, potatoes, corn, spaghetti
What are lipids?
Substances divided into fats (solids at room temperature) and oils (liquids at room temperature)
What do fats do? (2)
- insulate the body
- support and cushion organs
What do oils do? (2)
- store energy
- mostly in plants
Give properties of lipids (2)
- insoluble
- source of long-term energy once carbohydrates are burnt
What are the monomers of lipids?
glycerol and fatty acids (triglycerides)
- one glycerol molecule chemically bonded to three fatty acids
What elements make up lipids?
carbon, hydrogen, oxygen (CHO)
Give examples of lipids (name 3)
nuts, butter, olives, bacon, beef fat, seeds
What are proteins?
They are generically muscle builders that work in the immune system
- play an important role in the structure and efficient function of the body
What are the monomers of proteins?
Amino acids
- arranged in any order creating hundreds of thousands of proteins
Give examples of proteins (name 3)
lean meats, fish and seafood, eggs, dairy products, poultry
What elements make up proteins?
carbon, hydrogen, oxygen, nitrogen (CHON)
What are nucleic acids?
Macromolecules such as DNA and RNA
What is the monomer of nucleic acids?
Like proteins and carbohydrates, they are polymers (made up of smaller molecules in chains)
- subunits are called nucleotides
What elements make up nucleic acids?
carbon, hydrogen, oxygen, nitrogen, phosphorus (CHONP)
How do you test for starch?
Iodine turns from orangey brown to blue/black in the presence of starch
How do you test for lipids?
Using ethanol as a reagent
- shake the colourless ethanol together with the sample being tested
- positive test forms a cloudy white emulsion
