Chapter 3 Review Questions
Terms in this set (21)
Most human adults are lactose intolerant. People with lactose intolerance produce insufficient amounts of _______.
D. the enzyme lactase
The Enzyme Lactase
The large diversity of biological molecules depends on the element ________. This element can make stable bonds to itself and to atoms of other elements. Without this element, the large macromolecules that make up most of the molecules in living organisms would not be possible.
Hydrocarbons are organic molecules that contain only ______.
A. components found only in crude oil
B. carbon and hydrogen atoms
C. carbon atoms
D. carbon, hydrogen, and oxygen atoms
Carbon and Hydrogen Atoms
All organic molecules contain carbon and hydrogen. What parts of an organic molecule may contain oxygen, nitrogen, or phosphorus?
A. the nonpolar parts of an organic molecule
B. the hydrophobic parts of an organic molecule
C. the molecule's skeleton
D. functional groups
A dehydration reaction is the process in which _______.
A. water molecules are formed when polymers are synthesized from monomers
B. water molecules are attracted to each other
C. proteins are broken down to individual amino acids
D. water molecules are used as a source of raw material to break down polymers to monomers
Water molecules are formed when polymers are synthesized from monomers.
Which of the following pairs of molecules share the same chemical composition but differ in molecular structure?
A. starch and glycogen
B. glucose and fructose
C. DNA and RNA
D. lactose and sucrose
Glucose and Fructose
What is the main sugar used by cells for energy?
D. any polysaccharide
Glucose plus fructose forms a disaccharide called ______.
Plant cell walls consists mainly of ________.
The characteristic that all lipids have in common is that ________.
A. lipids are all acidic when mixed with water
B. they are all made of fatty acids and glycerol
C. in general, lipids have a low energy content
D. lipids generally don't dissolve in water
Lipids generally don't dissolve in water
"Saturated" fats __________.
A. are composed of at least three fatty acid molecules attached to a glycerol molecule
B. contain only single bonds in their fatty acid tails
C. are hydrophilic
D. mix easily with water
Contain only single bonds in their fatty acid tails
The building blocks of proteins are called _______.
B. amino acids
C. fatty acids
D. DNA and RNA
A polypeptide is a long chain of amino acids bonded together by __________.
A. phosphodiester bonds
B. hydration reactions
C. amino acid unique side groups
D. peptide bonds
A change in a single amino acid can change the structure and function of an entire protein. However, in some cases, there can be gene mutations, which change an amino acid in a protein structure but do not change either the overall shape or function of a protein. In cases like these, which level(s) of protein structure would change?
B. primary, secondary, tertiary, and quaternary
C. secondary and tertiary
The building blocks of nucleic acid molecules are called ___________.
C. amino acids
D. DNA and RNA
A specific stretch of DNA that codes for the amino acid sequence of a polypeptide is called a __________.
C. nucleic acid base
A shortage of phosphorus in the soil would make it especially difficult for a plant to manufacture ___________.
A. fatty acids
An important characteristic of the double-stranded DNA molecule is that ___________.
A. DNA is composed of amino acids linked together by peptide bonds that form a double helix.
B. DNA contains four nucleotides: cytosine, uracil, adenine, and guanine.
C. Phosphodiester bonds are formed between bases in opposing DNA strands to form a double helix.
D. Hydrogen bonding between base pairs is responsible for formation of a double helix.
Hydrogen bonding between base pairs is responsible for formation of a double helix.
One difference between DNA and RNA is that __________.
A. DNA is single-stranded, whereas RNA is double-stranded.
B. DNA uses ribose, whereas RNA uses deoxyribose.
C. DNA uses the bases CGAT, whereas RNA uses the bases CGAU.
D. DNA is a nucleic acid, and RNA is a protein.
DNA uses the bases CGAT, whereas RNA uses the bases CGAU.
As a result of experimentation on lactose-intolerant individuals, scientists found that ___________.
A. a small change in a DNA nucleotide sequence can have a major effect on the production of lactase
B. a mutation within the lactase gene is responsible for lactose intolerance
C. males are more likely to be lactose intolerant than females
D. the enzyme lactase is not encoded by a DNA gene
A small change in a DNA nucleotide sequence can have a major effect on the production of lactase.
As a result of studying lactose intolerance in people from different geographic regions, scientists were able to determine that _________.
A. there is no evolutionary significance to their study
B. mutations have nothing to do with evolution
C. there is only one possible mutation that will affect lactose intolerance
D. natural selection could favor anyone with a mutation for a permanently active lactase gene
Natural selection could favor anyone with a mutation for a permanently active lactase gene.