The independent variable is the seeds.
The statement is true. Dead zones are the zones of oxygen depletion, which is caused by excessive running off of the fertilizers into the water body. These chemicals, particularly the nitrates, which are used by algae etc. which bloom by using the nitrates and use the oxygen present in the water. When they die, oxygen levels become critically low till then, for other aquatic animals like fishes etc., to survive.
Answer:
- The blood group of the father must be B.
- The genotype of blood group would be
. - The Rh factor of the father can either be positive or negative.
- Thus, the genotype of Rh factor of father would be either Rr or rr.
Rh factor:
The phenotype of the mother Rh factor is positive. Thus, she can have Rr or RR as her genotype as positive is a dominant trait.
If the genotype of the mother is RR then all the offspring would be positive for Rh factor. However, one of the offspring is Rh negative, that means the mother must be heterozygous that is, Rr.
The genotype of the father can either be Rr or rr in order to produce offspring with positive as well as negative Rh.
Blood group:
The blood group of the mother is A. Thus, the genotype can either be
or
.
However, the blood groups of the children are O+ and B+.
Thus, the genotype of the mother must be heterozygous that is
.
The blood group of the father must be B with genotype
in order to produce offspring with blood group O and B.
Answer
Option C - Skeletal Muscles
Explanation
Antagonistic pairs are the muscles that are functionally opposite, if one produces flexion, then the other's primary action is an extension. Skeletal muscles work in pairs to move a bone so that the muscles can function properly. They contract the bone making nerves deliver a message to the brain. For example. Biceps and triceps. The lower arm is moved upwards when the biceps muscle contracts and the triceps muscle is relaxed and vice versa.