Answer:
A bottom-up system concentrates attention on how resources (space and nutrients) influence higher trophic forms , whereas a top-down system focuses on interactions at top level consumers (predators) and their prey influence on lower trophic forms.
Explanation:
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The correct answer to this question is letter "C) occupy different niches within the tree." Several species of warblers can live in the same spruce tree ONLY because they <span>occupy different niches within the tree. Hope this answer helps out your question. </span>
Answer:
1) In the first step, we need to predict the possible alleles for the cross. The dominant allele will be written with a capital letter. The recessive allele will be written with a small letter. Hence, the allele for brown hair colour will be B and the allele for red hair colour will be b.
2) In the second step, we need to determine the genotype of the parents. The genotype of the homozygous dominant parent will be BB. The genotype of the heterozygous brown hair colour will be Bb.
3) The punnet square for cross between these parents can be shown as follows:
B b
B BB Bb
B BB Bb
4) In the fourth step, lets determine the phenotype of the children. The phenotype of all the offsprings born will be brown hair colour.
5) The genotype from the punnet square shows that there is a 50% chance that the offsprings will be heterozygous dominant (Bb) for brown hair colour and their will be a 50% chance that the child born will be homozygous dominant (BB).
The odds are astronomical for a father with AB(IV) to have an O(I) child. The only possible way for this phenomenon to occur is if there was a nondisjunction in the ovogenesis for the 9th chromosome and the father also had a nondisjunction for the same chromosome(A sperm cell with no 9th chromosome fertilized an ovum with two 9 chromosomes).
A person with AB cannot donate to a person with O because the receiver has antibodies(alpha and beta) that bind to the antigens on the AB blood cells, causing death.
