AP BIOLOGY

Detailed explanation-1: -The shape of the seeds are controlled by two alleles Round (R) and Wrinkled (r). Round shape is the dominant one and wrinkled shape is the recessive trait. Now for wrinkled phenotype to be shown, the genotype has to be recessive homozygous. Therefore, the genotype of wrinkled phenotype is rr.

Detailed explanation-2: -Since capital R = round and is dominant that means that RR and Rr will all be round seeds. That means that ¾ or 75% of the offspring produced will be round. Since, wrinkled is rr, then ¼ or 25% of the offspring will be wrinkled. The genotype is the gene make-up of the offspring.

Detailed explanation-3: -A round seeded plant ( R ) is dominant to a wrinkled seeded plant ( r). What parental genotypes will produce offspring that are 50% homozygous dominant and 50% heterozygous dominant ? Q. Round seeded (RR) plant is crossed with wrinkled seeded plant (rr).

Detailed explanation-4: -The shape of the pea seeds is controlled by two alleles. S is dominant alleles and stands for smooth and s is recessive allele and stands for wrinkled. The wrinkled phenotype is shown when the genotype contains both the recessive alleles. The genotype of the wrinkled seeds of pea is ss.

Detailed explanation-5: -The physical appearance of an organism is its phenotype (wrinkled, smooth, yellow, green). This appearance is coded for by the alleles present for the gene. The actual alleles and genes that determine the phenotype are the genotype of a trait, and are illustrated using capital and lower case letters.