Morris is a big, healthy bull. One spring, he fathers ten calves, but five of them are stillborn, their muscles very rigid in a phenotype called "contracture." Farm animals often mate with their close relatives. So, three of the dams (mothers of the stillborns) are also Morris' daughters, and the fourth is his half-sister. The large number of stillborns is most likely due to
A) recessive lethal alleles that occur as new mutations in the doomed offspring.
B) dominant non-lethal alleles that Morris shares with his mates.
C) lethal alleles that Morris shares with his mates.
D) co-dominance between two lethal alleles.
C) lethal alleles that Morris shares with his mates.
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How did the development of anonymous markers aid in the production of a human genetic map?
A. Anonymous markers are genetic markers that do not cause a detectable phenotype, but can be detected by molecular techniques. The markers correspond to specific and unique chromosomal regions, thereby allowing for the identification and ordering of particular segments of DNA. Such information was essential to the generation of a human genetic map. B. Anonymous markers are genetic markers that cause a detectable phenotype and can't be detected by molecular techniques. The markers correspond to specific and unique chromosomal regions, thereby allowing for the identification and ordering of particular segments of DNA. Such information was essential to the generation of a human genetic map. C. Anonymous markers are genetic markers that do not cause a detectable phenotype, but can be detected by molecular techniques. The markers correspond to specific and unique genetic regions, thereby allowing for the identification and ordering of particular segments of the chromosome. Such information was essential to the generation of a human genetic map.
Sexual reproduction
A. allows more offspring to be produced per individual. B. allows a parent to pass on 100% of their genes to offspring. C. increases genetic variation. D. results in the formation of a haploid zygote. E. only occurs in vertebrates.
A bacterial cell wall that has primarily peptidoglycan with small amounts of teichoic acid and lipoteichoic acid is ________.
A. a protoplast B. gram-negative C. acid-fast D. gram-positive E. a spheroplast
Which of the following statements is false?
a. Ice is denser than liquid water. b. All living organisms require water. c. Water has cohesive properties. d. Water is a liquid at room temperature. e. All of the above are false.