The study pushes back the clock on the origin of Earth's water by hundreds of millions of years, to around 4.6 billion years ago, when all the worlds of the inner solar system were still forming. Scientists had suspected that our planet formed dry, with high-energy impacts creating a molten surface on the infant Earth.
Answer: 4.6 billion years.
Answer: The genotype ratio of offsprings of a cross between one homozygous tall plant and one heterozygous tall plant is 2TT:2Tt
The phenotype ratio is that all offsprings will be tall.
The genotype ratio of a cross between two heterozygous red flowers is 1RR:2Rr:2rr. The phenotype ratio is 3 Red flowers: 1 white flower.
Explanation: From the information given, tall is dominant and short is recessive while red is dominant and white is recessive.
Let T represent the allele for tall height, t represent the allele for short height, R represent allele for red flowers and r represent allele for white flowers.
The genotype of a homozygous tall plant is TT, the genotype of a heterozygous tall plant is Tt, the genotype of a heterozygous red flowered plant is Rr.
The possible genotypes of offsprings of a cross between one homozygous tall plant and one heterozygous tall plant are TT and Tt.
Tt will manifest outwardly as tall because T is dominant over t. Therefore, all the offsprings will be tall.
The possible genotypes of a cross between two heterozygous red flowers are RR, Rr and rr. RR will manifest as red, Rr will also manifest as red because R is dominant to r while rr will manifest as white because white allele (r) is recessive. Therefore 3 plants will be red-flowered while 1 plant will be white flowered.
See the attached punnet squares for details of the cross.
Answer: red flowers are rich in nectar
Explanation:
In animals, an important function of enzymes is to help digest food. Without digestive enzymes, animals would not be able to break down food molecules quickly enough to provide the energy and nutrients they need to survive.