In Drosophila, the allele red eyes (bw+) is dominant to the allele for brown eyes (bw). At another gene locus on the same chromosome, the allele for thin wing veins (hv+) is dominant to the allele for heavy wing veins (hv). Flies homozygous for bw and hv+ are crossed to flies homozygous for bw+ and hv to obtain doubly heterozygous F1 progeny.What would be the results of a test cross with the F1 flies?
A. 1 brown eye, thin wing veins: 1 red eye, heavy wing veins
B. 1 brown eye, heavy wing veins: 2 red eye, thin wing veins: 1 red eye, thin wing veins
C. 1 brown eye, thin wing veins: 2 red eye, thin wing veins: 1 red eye, heavy wing veins
D. 1 brown eye, heavy wing veins: 1 red eye, thin wing veins
Answer: A
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A) movement of the muscular layer surrounding the alimentary canal that is under voluntary control B) rhythmic waves of contraction of the muscular layer surrounding the alimentary canal that are responsible for moving contents of the lumen along the length of the digestive tract C) movement of nerve impulses from the central nervous system to the autorhythmic smooth muscle cells D) rhythmic lengthening and shortening of epithelial cells lining the lumen of the alimentary canal
The Shine—Dalgarno sequence is a purine-rich region just upstream of a start codon and is necessary for the initiation of protein synthesis in prokaryotes
Indicate whether the statement is true or false