Chapter 11 - Mendelian Stuff
A mother and father are both heterozygous for a trait. What is the chance that their offspring will not share this trait with them?
25%
Which duo conducted the experiment which proved that DNA was the genetic material?
Hershey and Chase
This is the only start codon
AUG
What is translation and where does it occur?
They are not just junk. They are involved in gene regulation.
Gregor Mendel proposed these laws
The laws of segregation and independent assortment.
What is Chargaff's rule?
DNA uses complementary base pairing to store genetic information
Modifications to the ends of a pre-mRNA
Poly-A tail (3' end), Guanine cap (5' end)
The tRNA binding sites facilitate complementary base pairing between...
tRNA anticodons and mRNA codons.
What is the function of introns?
Gene regulation, may encourage crossing over in meiosis
What is the purpose of a test cross?
To determine the genotype of an organism with a dominant phenotype.
Who discovered the helix model using x-rays? Then which duo founded the double helix model?
Rosalind Franklin, Watson and Crick
Small nuclear RNA (snRNA) function?
Intron splicing in higher eukaryotes
What are the 3 ribosome binding sites and what does their name mean?
E site - For exit
P site - For peptide
A site - For amino acid
What does the trp operon do if tryptophan is absent?
It produces tryptophan
What did Mendel use for his experiments and why?
Mendel used garden peas because they were easy to cultivate, had short generations, could be cross-pollinated by hand, true-breeding varieties available had simple, objective traits.
Which nucleotide bases are purine and which are pyrimidine?
Adenine and Guanine are purine. Cytosine, thymine, uracil are pyrimidine.
3 major types of RNA and function?
Messenger RNA (mRNA), transfer information from DNA to ribosomes in cytoplasm, Transfer RNA (tRNA), amino acid transfer, Ribosomal (rRNA), make up ribosomes.
What happens during elongation and termination in translation?
The ribosome reads down the mRNA and connects the corresponding amino acids into a chain. The ribosome reaches the stop codon and disconnects.
When is the lac operon maximally active?
In the absence of glucose
A father is heterozygous for 2 traits. A mother is heterozygous for the first, but homozygous recessive for the second. What are the chances their offspring will be heterozygous for both traits?
6/16
What are plasmids?
Small circular DNA that replicates separately from chromosomes
What are the three stages of transcription and what happens in them?
Initiation, RNA polymerase binds to the promoter. Elongation, RNA polymerase lays complementary pairs in a 3’ to 5’ direction. Termination, RNA polymerase reaches a stop sequence, releasing the mRNA
What happens in the initiation stage of translation?
Small ribosomal subunit attaches to mRNA transcript, initiator tRNA attaches to P site, large ribosomal subunit joins to the small.
What are proteases and what is their function?
They are enzymes that break down proteins to help regulate gene expression.