Answer:
rT rt
Rt RrTt Rrtt
rt rrtt rrtt
25% chances for the genotype to be heterozygous roll tongue and heterozygous longer second toe.
25% chances for the genotype to be heterozygous roll tongue and homozygous short toe.
50% chances for the genotype to be homozygous recessive no roll tongue and homozygous recessive short toe.
Phenotypes would be 25% tongue roll with longer toe. 25% tongue roll with shorter toe. 50% no tongue roll,shorter toe.
Water is less dense as a solid than as a liquid. Normally this is reversed. Water has its maximum density at 4 degrees Celcius.
The fact that ice is less dense than water allows it to float on top of ponds so fish, frogs, etc can survive winters.
True. :)))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))).
Answer:
c. Directional selection
Explanation:
Directional selection is a type of natural selection that occurs when selective pressure favors one extreme phenotype over any other phenotype existing in a population. Only one extreme phenotype is favored over time.
A good example of directional selection is the natural selection that occurs in giraffes, where alleles for long necks were favored against alleles for short necks as a result of selection pressure among the different phenotypes. Over time, giraffes having long necks dominated the population as the distribution of length of neck shifts towards the phenotype for long necks.
