1what did Fanklin do
produced x ray diffraction patterns of dna which showed that it was a helix
2produced x ray diffraction patterns of dna which showed that it was a helix
what did Fanklin do
3produced the first double helix model of dna
watson and crick
4watson and crick
produced the first double helix model of dna
5used bacteriophage viruses and radioactive sulfur and phosphorus to determine that DNA is the molecule that gene are made of
hershey and chase
6what is the purpose of transcription
to make pre-mRNA
7why is only 1 strand of DNA added to transcription
the preRNA created will have the same sequences as the already existing sense strand
8where does transcription occur
nucleus
9where does translation occur
ribosome
10what is the difference between an enhancer and silencers effect on gene expression
enhancer makes is easier faster, silencer makes it harder/slower
11alternative splicing of mRNA allows for ___ proteins to be created from a single gene
more
12the ribosome is made up of a small and big subunit. which binds the mRNA first
small unit
13which type of RNA carries the anticodon
trna
14which type of RNA carries the codon
mRNA
15what is carried at the top of tRNA and binds to the A site of the ribosome
amino acids
16how do the correct amino acids bind to the correct tRNA
energy from ATP --> AMP
17what enzyme is used to bind amino acid to tRNA
tRNA synthase
18translation of RNA into an amino acid chain continues until what is reached
stop codon
19explain how the relationship etween codons and anticodons allows for translation to occur
codons and anticodons have complementory base pairs. only correct base pairing will keep the ribosome signaaling for moreTrna with more animo acids. Translatiion - the changing of into another form--is where mRNA is used to collect and connect aminoo acids on tRNA
20what is the difference between the proteins that free ribosomes and bound ribosomes make
proteins from free are staying in the cell, proteins from bound are for other cells
21cuz prok cells no have nucleus, both transcription and transltion occur where in the cell
cytoplasm
22increased methylatin causes increased/decreased coiling of nucleosomes which enhances/limits the ability of transciption factors to access the DNA which mean thaat the genes in that area wwill be activated/silences
increase, limit, silence
23three environmental factors that can influence the level of methylation in cells
age, temp, nutrient supply, stress
24what is nucleosome composed of
histone proteins and DNA
25what links the pairs of complementary bases in a DNA double helix
hydrogen bonds
26the hershey chase exp supported DNA as the hereditary material. decribe the experiment
wanted to know if it was proteins or DNA that passed heredity. Raidated the sulfur in proteins to see if stuck w/ bacteria after centrifuge, result was no. Radiated the phosphorus in DNA to see if stick in bacteria after centrifuge, result was yes
27nucleic acids are polymers of nucleotides. what parts of nucleotides are join together in both DNA and RNA to make these polymers
pentose sugars with phosphates
28what happens during transcription in eukaryotes
RNA polymerase separates DNA strands
29how is the info in the genetic code used
to tranlate mRNA into polypeptides
30some yeast genes can be replaced by human genes that then cont to produce the same human proteins in the yeast cell. how?
yeast and humans are both eukaryotes
31outline the role of tRNA actiivating enzymes in translation
trna synthase is necessary in translation for providing charges and amino acids to tRNA. it is the enzyme responsible for providing energy to 1 amino acid in order for tRNA to be used over and over for multiple translations
32ouline the roles of diff binding site for tRNA on ribo during translation
A site: proofreads and binds codon w/ anticodon
psite: holds tRNA and make peptide bondsbetween amino aicds
e site: where used tRNA leaves ribo
33outline how translation depends on complementary base pairing
synthesis of polypeptide; need mRNA and tRNA and ribo; codons on mRNA have a mathc in tRNA anticodons determined by complementary base pairing ; when hydrogen bonds are made between codons and anticodons, tRNA, amino acid, attackes to growing polypeptide chain near E site
34some regions of DNA do not code for the production of PRoteins. what are these regions of DNA used as
gene regulation and coding for production of enzymes used in translation
35some regions of DNA act as telomeres or produce tRNA. state on function of DNA that no code for protein
enhancer to speed up RNA transcription silencer to slow down transcription
36gene expression in cells is regulated at various stages. during which stage does splicing of RNA occur
post transcription
37explain the control of gene expression in eukaryotes
- regulated by proteins that bind to specific base sequences in dna
- dna is loosened @ nucleosome portion, promoter region is accesible
- rna polymerase interacts w/ DNA and copies antisense strand into RNA