Exam 1 Flashcards
The chemical group at the 3’ end of a single polynucleotide chain is
Hydroxyl group
If a single gene has three alleles how many different genotypes are possible in a diploid organism?
6
Define true breeding
When an organism passes down a certain phenotypic trait to its offspring
A cross between two true breeding lines (one with dark blue and one with white flowers) produces F1 progeny with a 1:2:1 ratio of dark blue: light blue: white flowers. What genetic phenomenon is consistent with these results?
Incomplete dominance
The coding region of a mRNA (from initiation to termination codon) has 300 nucleotides. The initiation codon is located closer to the ___ end of the mRNA and the polypeptide encoded by this mRNA will be approximately ___ amino acids
5’
100
Both PKU and AKU are caused by rare recessive alleles. A person affected by PKU marries a person affected by AKU. What phenotype do you expect for their children?
All normal
The allele causing achondroplasia is lethal when homozygpus. n both parents are affected by achondroplasia, the probability of a child with achondroplastic short stature among the children that survive can be estimated as:
2/3
When DNA fragments are separated in an agarose gel under an electric field
They are separated according to size; shorter fragments move faster
A 9:3:3:1 ratio refers to
The phenotypic ratio in the F2 progeny of a dihybrid cross
In peas, the yellow allele is dominant. If a plant with yellow peas is crossed to a plant with green peas, the resulting plants are 50% yellow and 50% green. What is the genotype of the parents in this cross?
Yy and yy
What phenotypic ratio would you expect as a result of a test cross between a dihybrid organism and one that is homozygous recessive for alleles at two independent loci?
1:1:1:1
Idnetify 3 possible components of a DNA nucleotide:
deoxyribose, cytosine, phosphate group
A give protein is 210 amino acids long. The mRNA encoding the protein is at least
630 nucleotides long
A mRNA is translated ____
5’ to 3’
Polypeptide synthesis begins at the ___ and ends at the ____ end
Amino
Carboxyl
Black skin color is dominant to pink skin color in pigs. Two heterozygous black pigs are crossed. If these pigs produce a total of three piglets what is the probability that two will be pink and one will be black?
3/64
Dihybrid wild type males and females of Drosphelia are crossed. A vestigial wing and ebony body are inherited at independent loci and are recessive to full wing and gray body. 800 progeny are produced. How many are expected to have vestigial wings and gray bodies?
150
