DNA Flashcards
What is a bacteriophage?
virus that infects bacteria
What did Hershy and Chase discover about DNA?
DNA transfers genetic material, not protein.
What are the 3 main roles of DNA?
Store information, copy info onto m RNA, express info by instructing cells to do work
What did Avery discover?
discovered that even when harmful bacteria is heated to destroy the harmful toxins, its offspring still carry info that make it harmful…..cell info must be genetic and stored.
What is DNA?
nucleic acid made up of nucleotides.
A nucleotide consists of what 3 things?
5 carbon sugar, phosphate group, nitrogenous base
What binds nucleotides together?
a weak covalent bond with hydrogen and the link between the phosphate groups of 1 nucleotide to the next via the sugar
What does Chargaff’s rule state?
G=C and A=T
who discovered the DNA helix via an xray?
R. Franklyn, photo51
How did the double helix explain Chargaff’s rule?
2 strands of DNA that run in counter-parallel direction allows for smooth reproduction and replication
Replication?
duplicating DNA, during S phase in prophase
What is DNA polymerase? Functions (3)?
enzyme: 1. it helps split the DNA strands, 2. helps bind an original strand to a new daughter strand (or m RNA strand), 3. proofreads replications to make sure all is perfect.
telmors?
the tips of eukaryotic chromosomes that carry an enzyme, telomerase, which make sure their is no damage during cell reproduction
4 ways in which DNA replication differs in eukaryotes vr. prokaryotes.
- DNA in nucleus vr. cytoplasm 2. 1000x more DNA in a euk. cell vr. prokaryote. cell 3. replication can start from many points vr. a single point on a prok. cell 4. replication can start from different places at the same time in a eukaryote.
