Ashworth Basic Biology EXAM (Answered;graded A+)

A purebred plant that produces yellow seeds is crossed with a purebred plant that produces green seeds. The seeds of all of the offspring are yellow. Why? A) The yellow allele is recessive to the green allele. B) All of the offspring are homozygous yellow. C) The yellow allele is dominant to the green allele. D) The alleles are codominant. - Answer-C) The yellow allele is dominant to the green allele. A purebred plant that produces yellow seeds is crossed with a purebred plant that produces green seeds. The F1 plants have yellow seeds. What is the expected phenotypic ratio of seed color of the offspring of an F1× F1 cross? A) 1:2:1 B) 2:1 C) 3:1 D) 9:3:3:1 - Answer-C) 3:1 An individual who is homozygous ________. A) expresses the dominant trait B) carries two different alleles for a gene C) carries two copies of the same allele for a gene D) expresses the recessive trait - Answer-C) carries two copies of the same allele for a gene Which cross will produce only heterozygous offspring? A) AA � aa B) AA � AaC) Aa � Aa D) Aa � aa - Answer-A) AA � aa DNA contains the nitrogenous base ________ instead of ________, which is found only in RNA. A) a deoxyribose sugar; a ribose sugar B) uracil; thymine C) uracil; guanine D) thymine; uracil - Answer-D) thymine; uracil If one strand of a DNA double helix has the sequence ATCCGA, what is the sequence of the other strand? Question options: A) ATCCGA B) TAGGCT C) AGCCTA D) UAGGCU - Answer-D) UAGGCU What type of chemical bond joins the bases of complementary DNA strands? A) ionic B) covalent C) hydrogen - Answer-C) hydrogen If a strand of DNA has the sequence GACTTA, transcription from DNA to RNA will result as CTGAAT. True False - Answer-FalseTranslation converts the information stored in __DNA______ to ___RNA_____. True False - Answer-False Please read the following scenario to answer the following questions. Widow's peak, a pointed hairline on the forehead, is a genetic trait caused by a dominant allele. It can be traced back through a family's history using pedigree analysis. The pedigree shown here is of three generations of a family. Notice that some individuals (shown in gray) have a widow's peak (W = dominant allele and w = recessive allele). The genotype of Mary is Ww. True False - Answer-True A couple has two female children. The probability that their next child will be male will be 35%. True False - Answer-False An individual with (naturally) curly hair and an individual with (naturally) straight hair mate; all of their offspring have (naturally) wavy hair. The relationship between the alleles for hair texture is codominance. True False - Answer-False Mendel's laws are based on the behavior of chromosomes during prophase. True False - Answer-FalseHow many nucleotides make up a codon? A) two B) three C) four D) five - Answer-B) three