1.In dogs,trait A(erect ears and barking while following a scent)is caused by
dominant alleles; trait B(droopy ears and silence while following a scent)is
caused by recessive alleles.A dog that is homozygous for both traits is mated
to a dog with trait B.If the two genes are unlinked,which of the following are
expected F1 phenotypic ratios?
(A)9:3:3:1 (B)1:1 (C)16:0 (D)1:2:1 (E)None of the above
2.Which of the following statements about Mendelian genetics is flase?
(A)Individuals with the same phenotype can have different genotypes
(B)Only two alleles can exist for a given gene
(C)Alternative forms of genes are called alleles
(D)A locus is a gene's location on its chromosome
(E)A genotype is a description of the alleles that represent an individual's
genes.
3.The first repair of mistakes during DNA replication is made by
(A)the mismatch repair system
(B)DNA polymerase
(C)excision repair
(D)SOS repair
(E)postreplication repair
4.Centrosomes
(A)are constricted regions of phase chromosomes
(B)determine the plane of cell division
(C)are the central region of the cell
(D)are the region where the membrane constricts during cytokinesis
(E)are part of cilia
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