BIOLOGY CHAPTER 5 CARBOHYDRATES
If a DNA sample were composed of 10% thymine, what would be the percentage of guanine?
40
What is the complementary DNA sequence to 5' ATGCATGTCA 3'?
5' TGACATGCAT 3'
glycoprotein
a protein with one or more covalently attached carbohydrates.
Name of the pentose sugar found in DNA.
deoxyribose
Which of the following sugars is the sugar found in deoxyribonucleotides?
deoxyribose
triose
monosaccharide with 3 carbons
An RNA molecule that can catalyze chemical reactions is called a_____.
ribozyme
peptidoglycan
structural support of cell walls of bacteria
What feature of single nucleotides provides the energy needed for polymerization when nucleic acids are formed?
their phosphate groups
What are the complementary base pairs that form in DNA?
A-T and G-C
How are the structures of RNA and DNA similar?
Their sugar-phosphate backbones are formed by phosphodiester linkages.
True or false? Guanine and uracil are examples of nitrogenous bases.
True
Name the four nitrogenous bases that occur in DNA.
adenine, cytosine, guanine
pentose
monosaccharide with 5 carbons
glycogen
carbohydrate energy storage molecule in animals livers and muscles
starch
carbohydrate energy storage molecule of plants
What is the structural feature that allows DNA to replicate?
complementary pairing of the nitrogenous bases
isomers
compounds that have the same molecular formula but different molecular structures
The difference between the sugar in DNA and the sugar in RNA is that the sugar in DNA _____.
contains one less oxygen atom
Identify three possible components of a DNA nucleotide.
deoxyribose, phosphate group, thymine
lipid bilayers
forms when 2 sheets of lipid molecules align; the hydrophobic tails face inward and the phosphate heads face the surrounding watery solution
One of the primary functions of RNA molecules is to _____.
function in the synthesis of proteins
Which of the following did Watson and Crick already know when they were trying to determine the structure of DNA? The number of _____.
purines is always the same as pyrimidines
chitin
structural support of cell walls of fungi and external skeletons of insects
cellulose
structural support of cell walls of plants
In a DNA double helix an adenine of one strand always pairs with a(n) _____ of the complementary strand, and a guanine of one strand always pairs with a(n) _____ of the complementary strand.
thymine ... cytosine
Which of the following nitrogenous bases is found in RNA but is not found in DNA sequences?
uracil
QUANTITATIVE If nucleotides from the DNA of a human were quantified and 30 percent of them consisted of adenine, what percentage of guanine nucleotides would be present?
20 percent
If a DNA double helix contains 28% T nucleotides, then what is the percentage of A nucleotides?
28%
DNA molecules with a high percentage of guanine (G) and cytosine (C) are particularly stable. Why?
A G-C base pair has three hydrogen bonds, while an A-T base pair has two.
Which linkage forms the backbone of a nucleic acid?
A sugar-phosphate linkage
What do cells do to activate nucleotides for incorporation into a polymer and why?
Add phosphate groups to raise the potential energy of monomers.
Which statement concerning the DNA double helix is correct?
Base pairing allows production of identical daughter molecules.
Most biologists contend that the first life-form on Earth was a self-replicating RNA molecule, not DNA or protein. Which statement best explains why?
Only RNA can function as a catalyst and an information-containing entity.
Which statement accurately
Ribonucleotides have a hydroxyl group bonded to their 2' carbon; deoxyribonucleotides have an H at the same location.
Which structure is not a component of a nucleotide?
Sulfhydryl Oxygen group
Which of the following statements about DNA structure is true?
The nucleic acid strands in a DNA molecule are oriented antiparallel to each other.
Which of the following statements about nucleotide structure is false?
The phosphate group is bonded to the nitrogenous base
Which of the following descriptions best fits the class of molecules known as nucleotides?
a nitrogenous base, a phosphate group, and a sugar
What are the four nitrogenous bases found in DNA?
adenine, guanine, cytosine, thymine (A, G, C, T)
glycolipid
membrane carbohydrates that are covalently bonded to lipids
hexose
monosaccharide with 6 carbons
In a nucleic acid polymer, the bonds that help to hold regions of double-strandedness together occur between what parts of the nucleotide monomers?
nitrogenous bases
Nucleic acids are polymers made up of which of the following monomers?
nucleotides
permeability
of a structure is its tendency to allow a given substance to pass through it
Some viruses consist only of a protein coat surrounding a nucleic acid core. If you wanted to radioactively label the nucleic acids separately from the protein, you would use radioactive _____.
phosphorus
