Answer:
If both parents are heterozygous, the offspring have a 25% chance of being homozygous dominant.
Explanation:
A a
A AA Aa
a Aa aa
The scientist credited with being the first person to observe bacteria and call them as small animalcules is B. Anton van Leeuwenhoek.
Answer:
Frequency of heterozygous carriers of the allele in the entire herd is
i.e
out of 
Explanation:
It is given that a recessive allele pair produces a dwarf cow.
Let this recessive allele be represented by "t" and the dominant allele for tall height trait in cows be "T".
Given
Total population of randomly mating cows 
Total number of dwarf calves in the population 
Frequency of genotype "tt" producing dwarf calves is represented as
in HW equilibrium equation.
Here

Frequency of recessive allele is equal to "q"

As per first equilibrium equation of HW,
Frequency of genotype "TT" producing dwarf calves is represented as
in HW equilibrium equation.

As per HW's second equilibrium equation

Substituting the given values in above equation, we get -

Frequency of heterozygous carriers of the allele in the entire herd is
i.e
out of 
Answer:
All plants and animals need nitrogen to make amino acids, proteins and DNA, but the nitrogen in the atmosphere is not in a form that they can use.
Explanation:
When organisms die, their bodies decompose bringing the nitrogen into soil on land or into ocean water. Bacteria alter the nitrogen into a form that plants are able to use.
In order, the answers are position, Sun, and circular.