Answer:
The involvement of more than two genes.
Explanation:
The polygenic characteristics have many phenotypes because more than two genes governs the phenotype of individual organism. The single gene contains a pair of alleles that codes for two phenotype and two genes will code for 4 phenotype. Thus, more than two genes for example, three genes will have six phenotypes.
The skin color and height are polygenic characterstics in humans.
Answer is Middle Paleozoic era.
Paleozoic era was in 542 Ma - 245 Ma and it has 6 periods as Cambrian, Ordovician, Silurian, Devonian, Carboniferous and Permian.
360-280 Ma - forming of vascular plants with woody tissues, seeds and veins.
430 - 410 Ma - forming of jawed fishes and first amphibians.
420 Ma - forming of scorpions
360 Ma - forming of crustaceans.
Which mode of inheritance produces heterozygotes with phenotypes that differ from either homozygote but typically more closely resembles one homozygous phenotype than the other?"
A) complete dominance
B) incomplete dominance
C) codominance
D) epistasis
E) incomplete penetrance
Answer:
B) incomplete dominance
Explanation:
Incomplete dominance occurs when the dominant allele of a gene is not able to mask the expression of the recessive allele completely. This results in the expression of a phenotype in the heterozygous genotypes that differ from both homozygous genotypes. However, the phenotype of the heterozygote is closer to one of the homozygous genotypes.
For example, the petal color in four o'clock plant is controlled by a gene with two alleles R and r. Here, the "R" allele can not produce enough pigment in heterozygous conditions to completely mask the expression of the "r" allele and the phenotype of the "Rr" plant is "pink". On the other hand, the phenotype of "RR" plant is red while that of the "rr" plant is "white".
Answer:
NON DISJUNCTION: when 2 homologous chromosomes move to the same pole during meiosis. One daughter cell will be missing one chromosome while the other will have an extra chromosome.
Explanation:
Answer:
D
Explanation:
the circulatory absorbs nutrients and carries the chemical to signal through endocrine to control the speed of digestion.
