Answer:
during the Cambrian Period of the Paleozoic Era.
Explanation:
The Paleozoic is the earliest era (of three) of the Phanerozoic Eon and is composed of six geologic periods: the Cambrian, Ordovician, Silurian, Devonian, Carboniferous, and Permian (in that order from earliest to the latest). Fish first appeared about 530 million years ago during the Cambrian explosion.
Answer:
Biological evolution
Explanation:
<em>Biological evolution is defined as the formation of complex organisms from single ancestral type over a large time period. Evolution believes that all living organisms descended from a common ancestor but not without modification.</em>
There are several evidence to support the theory of evolution including morphological evidence, paleontological evidence, biochemical evidence, among others.
The similarity in the structure and components of DNA of all living organisms is one of the evidence pointing to the fact that living organisms might truly have been from a common ancestor. In addition, all living organisms tend to use ATP largely as their source of energy, giving further credence to evolution theory.
thymine
adenine
cytosine
guanine
Explanation:
uracil is not because uracil is only RNA.
Explanation:
The phenotypes and genotypes of the progeny can be determined by a dihybrid cross of the parents.
The heterozygous male will have the genotype 'SSww' and the heterozygous female will have the genotype 'ssWW'.
When crossed, the F1 offsprings will have a hybrid genotype of 'SsWw'. These offsprings are heterozygous with spotted skin and wooly hair.
On self-crossing of the F1 hybrids, we find four different combinations of the alleles- SW, Sw, SW and sw. The probability of getting each of these combinations is 1/4.
Hence, the probability of any dihybrid type is 1 out of the 16 possible genotypes. Using Punnet square, we find
9 SSWW: 3 SSww: 3 ssWW : 1 ssww
This is the phenotypic ratio of the offsprings.
The ratio of the possible genotypes will be 1:2:1:2:4:2:1:2:1.
It would be 6.6875 gram/ cubic centimeter