Chapter 8 Flashcards
(24 cards)
what does DNA stand for?
deoxyribonucleic acid
RNA and DNA are long chains of ____
nucleotides
what are the four nitrogen-containing bases of DNA?
adenine, thymine, guanine, cytosine
in 1953, watson and crick proposed that DNA is a double ____
helix
each nucleotide is made of three parts. what are they?
five carbon sugar, phosphate group, nitrogen base
viruses that infect bacteria are called…
(bacterio) phages
RNA and DNA are both…
nucleic acids
the sugar of DNA is called…
deoxyribose
what are the two double-ringed bases?
adenine, guanine
what are the two single-ringed bases?
thymine, cytosine
adenine always binds to ____
thymine
guanine always binds to ____
cytosine
characteristics of DNA:
a. ) consists of ____ nucleotide strands attached together
b. ) the strands are complimentary and ____
c. ) ____ hold the nitrogen-containing bases together
d. ) DNA molecule is a ____ shape
- two
- anti-parallel
- hydrogen bonds
- double helix
the hydrogen bonds between the nitrogen bases are easily ____
broken
the DNA unwinds at the ____ as the hydrogen bonds break
replication fork
one side of DNA serves as a ____ for replication
template
DNA undergoes ____, where one side is old and one side is new
semi-conservative replication
____ is an enzyme involved in DNA replication that unzips DNA by breaking hydrogen bonds between nitrogen bases
helicase
____ is an enzyme involved in DNA replication that attaches new nucleotides together
polymerase
____ is an enzyme involved in DNA replication that attaches new nucleotides together
ligase
____ is an enzyme invovled in DNA replication that repairs damaged sites or mismatches
repair enzyme; mismatch repair enzyme
strands can only be assembled in the ____ or ____ direction
5, 3
describe the assembly of DNA
on one strand, DNA is assembled continuously. on the other strand, it is assembled in fragments called okazaki fragments.
a. ) ____ cloning happens naturally
b. ) ____ cloning is where an unfertilized egg nucleus is replaced with another DNA
c. ) ____ cloning is where a stem cell nucleus is replaced with the nucleus of the organ to be cloned
embryo, reproductive, tissue
