How can all organisms share the same 4 bases DNA and still be so diverse?
what is the connection between a chromatid and a replicated DNA molecule?
Flower position, stem length, and seed shape were three traits that were studied by Mendel. Each is controlled by an independently assorting gene. If a plant that is heterozygous for all three traits was allowed to self- fertilize, what proportion of the offspring would be expected to show all three dominant phenotypes?
In cucumbers normal leaves (N) are dominant to curled leaves (n) and elongated fruit (L) is dominant to spherical fruit and these genes are linked on the same chromosome. If a pure-breeding normal-leaved, elongated fruit cucumber is crossed with a curled-leaved, spherical fruit cucumber, what will be the phenotype of the F1? the phenotypic ratio of the F2?
Explain in terms of gene product function how a mutant allele can be dominant? recessive?
In sesame, the one-pod condition (P) is dominant to the three-pod condition (p), and normal leaf (L) is dominant over wrinkled leaf (l). The two characters are inherited independently. Determine the genotypes and phenotypes of the two plants which produce the following progeny: 318 one- pod normal, 98 one-pod wrinkled, 323 three-pod normal and 104 three-pod wrinkled.
Flower position, stem length, and seed shape were three traits that were studied by Mendel. Each is controlled by an independently assorting gene. If a plant that is heterozygous for all three traits was allowed to self- fertilize, what proportion of the offspring would be expected to show all three dominant phenotypes?
In horses coat color is dependent upon genes as follows: A_B_ results in bay, aaB_ in black, A_bb in chestnut, aabb in liver. In addition, palimino is derived by Dd with chestnut. A palimono stallion (DdAAbb) is crossed with a palimino mare (DdAAbb). What percent of the offspring will be palimino?
In cats yellow is due to gene B and black to its allele b. These genes are located on the X chromosome (sex-linked). The heterozygous results in calico (tortoise shell). What kinds of offspring (sex & color) are expected from the cross: black male & calico female? Most calico males are sterile, why?
The ABO blood system has been employed to settle cases of disputed paternity. Suppose, as an expert in genetics, you are called to testify in a case where the mother is type A, the child is type O and the alleged father is type B. How would you respond to the following statements of the attornies: a. "Since the mother has type A, the type O of the child must have come from the father and since my client is type B, he obviously could not have fatered the child." Made by the attorney of the alleged father. b. "Further tests revealed that this man is heterozygous and therefore he must be the father." Made by the mother's attorney.
Consider two linked autosomal genes. The dominant allele C of the first gene causes cataracts of the eye, whereas its recessive allele produces normal eyes. The dominant allele P causes polydactyly (an extra finger) whereas its allele (p) produces a normal number of fingers. A man with cataracts and normal fingers marries a woman with polydactyly and normal eyes. Their son has both polydactyly and cataracts and he marries a woman with neither trait. What is the probability that their first child will have cataracts and polydactyly?
A number of plant species have a recessive allele for albinism; homozygous albino (white) individuals are unable to synthesize chlorophyll. If a tobacco plant heterozygous for albinism is allowed to self-pollinate and 500 seeds germinate: a)how many offspring will be the same genotype as the parent? b)how many seedlings would you expect to be white?
In mice colored coat is dominant to albinism. Sniffles, a male mouse with a colored coat is mated to Esmeralda, an alluring albino. The resulting litter of six young all had colored fur. The next time around Esmeralda was mated with Whiskers, who was the same color as Sniffles; some of this litter were white. a)What are the probable genotypes of Sniffles, Esmeralda, and Whiskers? b) If a male of the 1st litterwas mated to a colored female of the 2nd litter, what phenotypic ratio might be expected among the offspring? c)What would be the expected results if a male of the 1st litter was mated to an albino from the 2nd?
In hogs a gene that produces a white belt around the animal's body is dominant over its allele for a uniform body. Another independent dominant gene produces fusion of the hoof (syndactyly). Suppose a uniformly colored hog homozygous for syndactyly is mated with a normal footed hog homozygous for the belted character. What would be the phenotype of the F1? If the F1's interbreed, what would be the phenotypic ratio of the F2?
What are the differences between Genetic Engineering and breeding?
