four criteria that genetic material must meet
transmission, replication, information, variation
gene
segment of DNA that contains the information necessary to produce a functional product
what are DNA’s functional products
polypeptide/ protein, rRNA, tRNA other functional RNAs
gene expression process
gene goes through transcription with mRNA and then translation to become a protein which functions in a specific manner
physiological traits
traits that impact an organisms ability to function
allele
alternative version of a gene
diploid
2 copies of each chromosome
haploid
1 copy of each chromosome
frederick Griffith
microbiologist interested in pneumonia, grew it on a petri dish and did the experiment with two different bacteria strains and mice DISCOVERED THE TRANSFORMING PRINCIPLE
why did the smooth cells cause disease in mice
because the polysaccharide shell on it prevented the bacteria from being attacked by its immune system
what happened when heat killed smooth bacteria combined with alive rough bacteria?
the mouse died because the rough bacteria was able to inherit the genetic material from the smooth bacteria that helped it stay alive inside the mouse and ultimately kill it
what was used to breakdown outside components and make sure what was being transferred between bacteria was DNA
enzyme, specifically protease
gregor mendel
started the study of DNA, indicated that this held the basis of phenotypes
hershey and chase experiment
found that DNA is the genetic material, used bacteriophage (viruses that infect bacteria) made of protein and DNA. Used phosphate to label DNA sulfur for protein. Used a centrifuge to break up, found that DNA was present in the cell and protein was outside of the cell, determined that DNA was the genetic material.
Purines
adenine and guanine, double ring
pyrimidines
cytosine, uracil, thymine, single ring
nucleotide
sugar, phosphate, base
nucleoside
sugar, base
where does the base attach
to the 1’ carbon
where does the OH group attach
to the 3’ carbon
whats different between DNA and RNA
thymine replaced w/ uracil, OH group found on 2’ carbon in RNA not in DNA
what forms the backbone of DNA
phosphate and sugars connected by phosphodiester linkage at the OH group on the 3’ carbon
what is the DNA molecule’s charge
negative, the phosphates are negatively charged
rosalind franklin
discovered that DNA has a helical structure and there is more than one DNA strand, also there is 2nm spacing between bases, suggesting the A/T G/C rule.
erwin chargaff
discovered the A/T G/C rule, isolated DNA from cell and used protease to get rid of the proteins, hydrolyzed it with acid to dissolve the backbone & only be left with bases. Then used chromatography to find the percentage of each base, found that A&T were similar and G& C were similar.
watson and crick
modeled out the double helix structure
how many hydrogen bonds between A & T
two
how many hydrogen bonds between G & C
three