Carbohydrates & lipids Flashcards
What are monomers and polymers?
Monomers: Smaller units from which larger molecules are made (e.g., monosaccharides, amino acids, nucleotides). Polymers: Molecules made from a large number of monomers joined together.
What are the monomers of carbohydrates called?
Monosaccharides are the monomers of carbohydrates.
What are three examples of common monosaccharides?
Glucose, galactose, and fructose.
What is the general formula of a monosaccharide?
(CH2O)n, where n = 3-7.
What is a disaccharide?
A pair of monosaccharides joined together.
What are polysaccharides?
Many monosaccharides joined together.
Why is carbon important for life?
Carbon atoms readily form bonds with other carbon atoms, creating large chains of carbon atoms to which other atoms can attach. This allows for a variety of molecules based on carbon.
What is glucose classified as, and what is its formula?
Glucose is a hexose sugar (6-carbon sugar) with the formula C6H12O6.
What are the two isomers of glucose?
Alpha-glucose and beta-glucose.
How are disaccharides formed?
Two monosaccharides join by a condensation reaction, forming a glycosidic bond.
How can glycosidic bonds in disaccharides be broken?
By adding water in a hydrolysis reaction.
Name the products of glucose + glucose, glucose + fructose, and glucose + galactose.
Maltose, sucrose, and lactose, respectively.
What is a polysaccharide, and how is it formed?
A polysaccharide is formed from many monosaccharides joined by glycosidic bonds through condensation reactions.
Where is starch found, and what is its function?
Starch is found in plants and small grains. It functions as energy storage.
How is glycogen different from starch?
Glycogen has shorter chains and is more highly branched than starch.
Where is glycogen found, and what is its function?
Glycogen is found in animals and bacteria (liver and muscle) and functions as energy storage.
What is cellulose made of, and what is its role?
Cellulose is made of beta-glucose with straight, unbranched chains. It provides rigidity to plant cell walls by forming hydrogen bonds between chains.
Why is starch a good storage molecule?
Starch is insoluble (does not affect water potential), compact (stored in a small space), and made of alpha-glucose for respiration.
Why is glycogen suitable for energy storage in animals?
It can be hydrolyzed easily, is insoluble (does not affect water potential), and is compact for storage in small spaces.
What makes cellulose strong and rigid?
Cellulose has many hydrogen bonds between parallel chains, providing strength and rigidity to plant cell walls.
What are lipids classified as, and what are the two main types?
Lipids are classified as triglycerides/diglycerides. Types: Saturated (no double bonds) and unsaturated (at least one double bond).
What are the uses of lipids in the body?
Protection (shock absorption), insulation, waterproofing, and energy storage.
What is a triglyceride made of, and how is it formed?
A triglyceride is made of one glycerol and three fatty acids, formed by a condensation reaction that creates ester bonds.
What are the differences between phospholipids and triglycerides?
Phospholipids have two fatty acids (not three), a phosphate head, and a hydrophobic/hydrophilic part.
