Mendel/Exceptions to Mendel
Explain the difference between cross fertilization and self fertilization. What is the importance of each of these?
Name the 3 parts of the nucleotide in DNA
Deoxyribose, a phosphate group, and a nitrogenous base
Explain the central dogma of biology.
DNA to RNA through transcription; RNA to protein through translation
Translate this code into amino acids:
5' - AUG UCA CAA CGU UGA - 3'
Methionine, Serine, Glutamine, Arginine, STOP
What are introns and exons?
Introns - non coding (junk)
Exons - coding mRNA
Explain the laws of segregation and independent assortment
Segregation: Two diff. alleles segregate from each other during meiosis
Independent Assortment:Genes located on separate chromosomes sort independently of each other during meiosis
Is replication semiconservative, conservative, or dispersive? What does that mean?
Semiconservative, 1/2 old, 1/2 new
In bacteria, what signifies the start of transcription? What about in eukaryotes?
What signifies the end in both?
Sigma in bacteria; transcription factors in euk.
Hairpin loop in bacteria; 3' poly A tail in euk.
What is the complementary code of tRNA (to the mRNA strand) called?
Anticodon
What enzyme is required for intron splicing?
Spliceosome
What is the difference between pleiotropy and epistasis?
Pleiotropy says that one allele causes many phenotypes
Epistasis says that many alleles work together to express one phenotype
Explain which way DNA polymerase reads and writes on the template strand of DNA
Reads 3' - 5'
Writes 5' - 3'
What are the 3 modifications of eukaryotic mRNA after transcription?
1) 5' capping
2) 3' poly-A signal
3) Intron removal
What are the three different types of RNA? Which one codes for amino acids?
mRNA, tRNA, rRNA; mRNA is what we use to code proteins
Explain the process of alternative splicing, as well as its overall importance in biology.
Splicing out certain exons with the introns to get different protein formation. This allows for different proteins to be created based on the specific and necessary functions of the body at the time of gene expression.
We are uncertain of the genotype of a pea plant dominant for stem height. What would we use to determine this genotype, and how would you set it up?
Test cross; Cross the dominant individual with an individual homozygous recessive for the trait
Explain the Hershey-Chase Experiments. What is the final conclusion?
They radioactively tagged P (DNA) and S (Proteins) and injected the radioactive virus into E. coli cells. After centrifugation, it was found that only DNA was found at the bottom in the pellet, showing that DNA and not protein is the genetic basis for life
Transcribe this sequence of DNA:
3' -- CAG GTA CTA CAG CTG CCC -- 5'
5' -- GUC CAU GAU GUC GAC GGG -- 3'
What are the three sites of the ribosome in which translation (elongation) occurs; what happens at each site?
A - Arrive (tRNA brings the amino acid in)
P - Peptide bond forms between amino acids
E- Exit (tRNA exits the ribosome)
In the example of the cat that changes fur color based on temperature, explain how alternative splicing may come into play based on the differentiation between the expression of genes for coat color.
Based on temperature, different exons are spliced out of the mRNA sequence in order to code for the different coat colors, based on the temperature of the cat's environment.
Purple flowers are dominant to white flowers in a plant. If we cross a homozygous dominant individual with a heterozygous individual, what percentage of the offspring will be heterozygous for the trait?
50%
The 2' carbon (OH in DNA, just H in RNA)
What are the 3 key differences between prokaryotic and eukaryotic transcription?
1) Transcription and Translation are separated (nucleus vs. cytoplasm)
2) Initiation complex uses transcription factors instead of sigma
3) mRNA modification occur
DNA: 3' ATG - CTC - CAC - GTA- TGA 5'
What amino acid sequence does the DNA strand above code for?
Met, Leu, His, Val, Stop
Name all of the different types of mutations and what they each individually mean.
Point mutations (change one nucleotide):
-Missense (change one and the amino acid changes)
-Silent (change one and the amino acid stays the same)
-Nonsense (change on and it codes for a stop codon)
Frameshift: addition or deletion of codons that ARE NOT MULTIPLES OF 3, which causes the shifting of the reading frame and the coding of a nonfunctional protein, if any protein at all