12 Flashcards
Transformation
One strain of bacteria (harmless) had apparently been changed permanently into another (the disease causing)
Griffith
Bacteria, discovered things
Avery
Discovered that the nucleic acid DNA stores and transmits the genetic information from one generation of an organism to the next
Hershey-Chase
studied viruses, nonliving particles smaller than a cell that can infect organisms
-discovered radiation in bacteriophage phosphorous-32 in bacterium
Bacteriophage
“Bacteria eater” virus that infects bacteria
Genes must do which four things
- ) carry information from one generation to the next
- ) put that information to work by determining the heritable characteristics of organisms
- ) genes had to be easily copied
- ) capable of mutation
* dna does this all*
Nucleotides
DNA is a long molecule made up of these units
5-carbon sugar, phosphate, nitrogenous base
Purines
Have two rings (adenine and guanine)
Pyrimidines
One ring- cytosine and thymine
Backbone of DNA
Formed by sugar and phosphate
Chargaff’s rules
Found that G = C and A= T
Franklin
X-Ray diffraction
Showed that DNA stands are twisted around each other and that nitrogenous bases are near the center
Watson and crick
Figured out hydrogen bonds and the double helix using franklin’s work
Base pairing
Watson and crick found that every base has exactly another; explained chargaff’s rules
Two stands are said to be…
Antiparallel (facing opposite directions)
Prokaryotes have DNA in the…
Cytoplasm
Most eukaryotes have as much as___times the amount of DNA as prokaryotes
1000
DNA molecule must be folded into a space..
Only one thousandth of its length
Chromatin
Eukaryotic chromosomes contain both DNA and protein, tightly packed together to form chromatin
Histones
Chromatin consists of DNA tightly coiled around proteins called Histones
Nucleoside
DNA and Histones molecules together form this headline structure
Complementary
DNA strands are said to be complementary because each strand of DNA can be used to make the other strand
Replication forks
The sites where separation and replication occur
Replication
Copying process that duplicates DNA before a cell divides