Chapter 5: The Structure and Function of Large Biological Molecules Flashcards
What are carbohydrates ? Describe its function and name examples.
Carbohydrates serve as fuel and building material. Examples are glucose and fructose which are monosaccharides and lactose and sucrose which are disaccharides.
What are lipids? Describe its function and name example(s).
Lipids serve as an important energy source. Some examples are triglycerides, phospholipids and steroids.
What are proteins? Describe its function and name example(s).
A protein is a biologically functional molecule made up of one or more polypeptides, each folded and coiled into a specific three- dimensional structure. Proteins have many functions, some of are that include catalyzing chemical reactions, protecting against disease, transport substances, and storing amino acids. Some examples are enzymes, defensive proteins, and hormones
What are nucleic acids? Describe its function and name example(s).
Nucleic acids store, transmit, and help express hereditary information. Some examples are DNA (Deoxyribonucleic acid) and RNA (Ribonucleic acid)
What is a a polymer?
A polymer is a long molecule consisting of many similar or identical building blocks linked by covalent bonds.
What is a monomer?
The repeating units that serve as the building blocks of a polymer are smaller molecules is a monomer.
What is dehydration reaction?
A reaction in which two molecules are covalently bonded to each other with the loss of a small molecule. If a water molecule is lost, it is known as a dehydration reaction.
What is hydrolysis?
A process that is essentially the reverse of the dehydration reaction. Hydrolysis means water breakage (from the Greek hydro, water, and lysis, break).
What is a monosaccharide? What groups does it contain?
Monosaccharides (from the Greek monos, single, and sacchar, sugar) generally have molecular formulas that are some multiple of the unit CH2O. Glucose (C6H12O6), the most common monosaccharide, is of central importance in the chemistry of life.
The molecule has a carbonyl group and multiple hydroxyl groups.
What is the function of monosaccharides?
They function as the raw material for the synthesis of other monomers, such as amino acids and fatty acids.
What is a disaccharide?
A disaccharide consists of two monosaccharides joined by a glycosidic linkage.
What is a glycosidic linkage?
A covalent bond formed between two monosaccharides by a dehydration reaction (glyco
refers to carbohydrate).
What is a polysaccharide? What is its function?
Polysaccharides are macromolecules, polymers with a few hundred to a few thousand monosaccharides joined by glyco- sidic linkages. It serves for storage and are hydrolyzed as sugars are needed.
What is starch?
A polymer of glucose monomers, as granules within cellular structures known as plastids. The simplest form of starch is amylose which forms an unbranched helix.
What is glycogen?
A polymer of glucose that is like amylopectin but more extensively branched. Animals store glucose in glycogen.
What is amylopectin?
A more complex starch, is a branched polymer with 1–6 linkages at the branch points.
What is cellulose?
A major component of the tough walls that enclose plant cells.
What is chitin?
The carbohydrate used by arthropods (insects, spiders, crusta- ceans, and related animals) to build their exoskeletons—hard cases that surround the soft parts of an animal
What are lipids?
Lipids are the one class of large biological molecules that does not include true polymers, and they are generally not big enough to be considered macromolecules. The compounds called lipids are grouped with each other because they share one important trait: They are hydrophobic: They mix poorly, if at all, with water. This behavior of lipids is based on their molecular structure.
What is a fat?
A fat consists of a glycerol molecule joined to three fatty acids. Glycerol is an alcohol; each of its three carbons bears a hydroxyl group.
What is a fatty acid?
A fatty acid has a long carbon skeleton, usually 16 or 18 carbon atoms in length. The carbon at one end of the skeleton is part of a carboxyl group, the functional group that gives these molecules the name fatty acid.
What is a glycerol?
A three carbon alcohol with a hydroxyl group attached to each carbon.
What is a saturated fatty acid?i
If the fatty acid has no carbon carbon double bonds, then the molecule is a saturated fatty acid.
What is an unsaturated fatty acid?
If the fatty acid has one or more carbon carbon double bonds formed by the removal of hydrogen atoms from the carbon skeleton, then the molecule is an unsaturated fatty acid.