Chapter 5 The Structure And Function Of Large Biological Molecules Flashcards
Of the four main classes , which ones are macromolecules
Carbohydrates , proteins , and Nucleic acids
What are the four main classes of molecules of organic compounds
Carbohydrates
Lipids
Proteins
Nucleic acids
What is the significance of the architecture if a large biological molecule?
Helps explain how that molecule works
Polymer
A long molecule consisting of many similar to identical building blocks linked by covalent bonds
Monomers
The repeating units that serve as the building blocks of a polymer
The chemical mechanisms by which cells make and break down polymers are basically ______ in all cases
The same
Enzyme
Specialized macromolecules that speed up chemical reactions
How are monomers connected
By a reaction in which two molecules are covalently bonded to one another with the loss of a water molecule
Dehydration reaction
When a bond forms between two monomers each monomer contributes part of the water part of the water molecule that is released during the reaction: one monomer provides the hydroxyl group –OH While the other provides the hydrogen. This is repeated as monomers are added to the chain one by one making a polymer
Polymers are disassembled to monomers by _____
Hydrolysis
Hydrolysis
A process that is essentially the reverse of the dehydration reaction. Means to break using water
Explain hydrolysis
The bond between the monomers is broken by the addition of a water molecule, with the hydrogen from the water attaching to the adjacent monomer
Example of hydrolysis
Digestion within our bodies; the bulk of the organic material in our food is in the form of polymers that are much too large to enter our cells. Within the digestive tract, various enzymes attack the polymers, speeding up hydrolysis. The released monomers are then absorbed into the bloodstream for distribution to all body cells. Those cells can then use dehydration reactions to assemble the monomers into new different polymers that can perform specific functions required by the cell
Carbohydrates
Includes both sugars and polymers of sugars
The simplest carbohydrates
Monosaccharides or simple sugars . Which are monomers from which more complex carbohydrates are constructed
Disaccharide
Double sugars consisting of two monosaccharides joined by a covalent bond
Polysaccharide
Polymers composed of many sugar building blocks
Monosaccharides
Generally have molecular formulas that are some multiple of the unit CH2O.
Glucose
C6H12O6. The most common monosaccharide, is of central importance in chemistry of life.
Disaccharide
Consisted of two monosaccharides joined by a glycosidic linkage
Glycosidic linkage
A covalent bond formed between two monosaccharides by a dehydration reaction
Polysaccharide
Macromolecules; polymers with a few hundred to a few thousand monosaccharides joined by glycosidic linkages. Some serve as storage material, hydrolyzed as needed to provide sugar for cells. Others serve as building materials for structures that protect the cell or the whole organism
What determines the architecture and function of a polysaccharide
It’s sugar monomers and by the positions of its glycosidic linkages
Starch
Plants store starch, A polymer of glucose monomers
How is starch stored by plants
Plants store starch as granules within cellular structures known as plastids. Which include chloroplasts.
What does synthesizing starch allow a plant to do ?
Enables a plant to stockpile surplus glucose. Because glucose is a major cellular fuel, starch represents stored energy
