Chapter 13 Review Questions Flashcards
What is the difference between a genome and a gene?
Genome: made up of all the genetic information in a cell
Gene: a small subsection of the genome that codes for a single protein
A. What 3 units must be present in a nucleotide?
B. What type of bonding holds these three units together?
A. A nucleotide links a nitogen-containing base, a sugar, and a phosphate group
B. Covalent bonds
Explain why the base sequence ATG is different from the base sequence GTA.
Even though the base sequences are the reversal of each other, they code for two completely different codons/amino acids.
ATG for methionine (met) and GTA for valine (Val)
Explain why the base sequence ATG is different from the base sequence GTA.
Even though the base sequences are the reversal of each other, they code for two completely different codons/amino acids.
ATG for methionine (met) and GTA for valine (Val)
TATCTAG: a given short sequence of DNA
Write and align a DNA code that complements the sequence given
ATAGATC
Why are adenine-thymine base pairs less stable than cytosine-guanine base pairs?
They’re less table because they have fewer hydrogen bonds holding them together r
Ionizing radiation (or the free radicals it generates in the cell) can break covalent bonds to disrupt one or more strands of DNA. A cell can more easily repair damage to a single strand in a DNA double helix than repair a double-strand break. Why is this?
-the strands are complementary, meaning that the sequence on one strand can be reconstructed from the other
-if a single strand breaks, the other strand can be used by repair enzymes to correctly replace any lost nucleotides and reassemble the backbone.
-if both strands break, the information on how to repair the break is lost and the correct sequence of DNA will be permanently altered.
Errors in DNA duplication can alter the base sequence of a strand permanently. But not all of these errors result in the incorporation of an incorrect amino acid in a protein of which the DNA codes. Explain why a single base change many not change the amino acid.
Many amino acids are represented by more than one DNA codon
-if an error i the base sequence of DNA did not change the meaning of codon, the protein would contain the correct amino acid, makes the genome more resilient to change
List two advantages and disadvantages of issuing patents for genetically modified plants and seeds
Advantages: it provides financial incentive to perform the extremely expensive research required
-it increases the control and decreases the speed of artificial GM crops
Disadvantages: prevents the creative and traditional breeding process by farmers and smaller-scale plant breeds
-halts further research by academic scientists into a specific gene
