dna Flashcards
What is the name for the spiral shape of DNA?
Double helix
What type of macromolecule is DNA, and what is its monomer?
nucleic acids - nucleotide
structure of a nucleotide.
5-carbon sugar (ribose or deoxyribose), phosphate, nitrogen base
Name the four nitrogen bases found in DNA and indicate which pairs with which.
Adenine –> Thymine
Guanine –> Cytosine
What are the “sides” of a DNA ladder made out of? What are the “rungs”?
sides: alternating sugars (that bases attach to) and phospates
rungs: nitrogen bases (A, T, G, C)
What type of bond holds the bases together?
hydrogen bond
In a double helix of DNA, what bases would be on the strand opposite of the following bases?
A C C G T T A A C G T
T G G C A A T T G C A
What do the enzymes helicase and DNA polymerase do?
helicase unzips DNA, DNA polymerase creates new DNA from nucleotides
In DNA replication, how many double helixes do you start with, how many do you end up with, and how do they compare to each other?
start with one double helix that becomes two identical double helixes
Define semi-conservative and explain how it relates to DNA replication.
Semi-conservative means that after DNA replication the new double helix has one rung from the old DNA strand and one brand new rung from new nucleotides
What transcription, and where does it take place?
when DNA is copied over into RNA, in the nucleus
What is translation, and where does it take place?
when mRNA becomes proteins, in the ribosome
Explain the job of messenger RNA (mRNA) and the job of transfer RNA (tRNA).
mRNA tells your body how to make proteins, tRNA turns the mRNA into amino acids
What is a codon and an anticodon?
codon: three nucleotides in an mRNA strand that code for certain amino acids
anticodon: three nucleotides in a tRNA strand that code for certain amino acids
What is the monomer of a protein?
amino acids
What is a mutation? Are they good or bad?
a change in the genetic code of an organism, can be either good or bad
What is the difference between a gene mutation and a chromosomal mutation?
gene mutation: alters a single gene
chromosomal mutation: alters a chromosome or its structure
point mutation (gene mutation)
a replacement of one chemical base with another, which changes the type of codon
frameshift mutation (gene mutation)
a deletion of the chemical base, which shifts all of the bases and results in a mRNA sequence with entirely new codons
deletion (chromosomal mutation)
One base is removed from the sequence
duplication (chromosomal mutation)
A base is duplicated and the exact same base is formed as an addition to the sequence
inversion (chromosomal mutation)
The first and last bases are swapped
translocation (chromosomal mutation)
Bases go from one chromosome to another
