Biology 1408 Chapter 3
Why are biological macromolecules considered organic?
Biological macromolecules are organic because they contain carbon.
cellulose
polysaccharide that makes up the cell wall of plants; provides structural support to the cell
Describe the similarities and differences between glycogen and starch.
Glycogen and starch are polysaccharides. They are the storage form of glucose. Glycogen is stored in animals in the liver and in muscle cells, whereas starch is stored in the roots, seeds, and leaves of plants. Starch has two different forms, one unbranched (amylose) and one branched (amylopectin), whereas glycogen is a single type of a highly branched molecule.
What role do electrons play in dehydration synthesis and hydrolysis?
In a dehydration synthesis reaction, the hydrogen of one monomer combines with the hydroxyl group of another monomer, releasing a molecule of water. This creates an opening in the outer shells of atoms in the monomers, which can share electrons and form covalent bonds.
Why is it impossible for humans to digest food that contains cellulose?
The β 1-4 glycosidic linkage in cellulose cannot be broken down by human digestive enzymes. Herbivores such as cows, koalas, and buffalos are able to digest grass that is rich in cellulose and use it as a food source because bacteria and protists in their digestive systems, especially in the rumen, secrete the enzyme cellulase. Cellulases can break down cellulose into glucose monomers that can be used as an energy source by the animal.
during the breakdown of polymers, which of the following reactions takes place? a. hydrolysis b. dehydration c. condensation d. covalent bond
a. hydrolysis
dehydration synthesis
also, condensation; reaction that links monomer molecules together, releasing a molecule of water for each bond formed
plant cell walls contain which of the following in abundance a. starch b. cellulose c. glycogen d. lactose
b. cellulose
lactose is a disaccharide formed by the formation of a ________ bond between glucose and _______________ a. glycosidic; lactose b. glycosidic; galactose c. hydrogen; sucrose d. hydrogen; fructose
b. glycosidic; galactose
carbohydrate
biological macromolecule in which the ratio of carbon to hydrogen and to oxygen is 1:2:1 carbohydrates serve as energy sources and structural support in cells and form the a cellular exoskeleton of arthropods
dehydration synthesis leads to formation of a. monomers b. polymers c. water and polymers d. none of the above
c. water and polymers
polymer
chain of monomer residues that is linked by covalent bonds, polymerization is the process of polymer formation from monomers by condensation
an example of monosaccharide is a. fructose b. glucose c. galactose d. all of the above
d. all of the above
cellulose and starch are examples of a. monosaccharides b. disaccharides c. lipids d. polysaccharides
d. polysaccharides
biological macromolecule
large molecule necessary for life that is built from smaller organic molecules
polysaccharide
long chain of monosaccharides; may be branched or unbranched
hydrolysis
reaction causes breakdown of larger molecules into smaller molecules with the utilization of water
monosaccharide
single unit or monomer of carbohydrates
monomer
smallest unit of larger molecules called polymers
glycogen
storage carbohydrate in animals
starch
storage carbohydrate in plants
disaccharide
two sugar monomers that are linked together by a glycosidic bond
chitin
type of carbohydrate that forms the outer skeleton of all arthropods that include crustaceans and insects; it also forms the cell walls of fungi