Genetic variation can be caused by mutation (which can create entirely new alleles in a population), random mating, random fertilization, and recombination between homologous chromosomes during meiosis (which reshuffles alleles within an organism's offspring).
Answer:
Ball - stick - Ball
Explanation:
The ball represents the hydrogen atom and the stick represents the bond formed between them.
Explanation:
In humans, each cell normally contains 23 pairs of chromosomes, for a total of 46. Twenty-two of these pairs, called autosomes, look the same in both males and females. The 23rd pair, the sex chromosomes, differ between males and females.
Using two heterozygous tall pea plants, so Tt is the genotype.
T t <---- alleles from parent one
T TT Tt
t Tt tt
^alleles from parent two on the left
Results: TT, Tt, Tt, and tt
Genotype ratio: 1/4 TT, 1/2 Tt, 1/4 tt
Phenotype ratio: T is dominant over t, so 3/4 tall and 1/4 short pea plants
For Absolute dating they assign a numerical date to each rock layer studied
For relative dating they go Through geological dating and stratigraphy processes. Also, they use Uranium Dating.