Answer:
The question is incomplete, it lacks the main questions, those questions are:
a. What is the genotype for black chickens?
b. What is the genotype for white chickens?
c. What is the genotype for erminette chickens?
Explanation:
This question involves a gene coding for feather colour in some birds, in which the black allele (B) and white allele (W) is involved. According to the question, the gene coding for feather colour exhibits co-dominance i.e. both the black (B) and white (W) allele are expressed in a heterozygous state (BW) to form an erminette phenotype.
Hence, if the neither alleles is dominant or recessive over the other. The black phenotype will only be expressed when the genotype is BB.
The white phenotype will only be expressed when the genotype is WW
The combination of both alleles which results in the simultaneous expression of both in the erminette phenotype, will be BW genotype.
Answer:
If an individual Drosophila has two or more populations of cells comprising different genotypes from one single egg then it is termed as twin spots or mosaic.
Explanation:
There might be different reasons for mosaic to occur like
Nondisjunctioning of the chromosomes
Lag in anaphase
Endoreplication
Mutations in a single cell
Mitotic recombination:
One of the major ways through which mosaic or twin spots arise is the mitotic recombination. It is also termed as somatic cross over. Twin spot or mosaic generally occurs if there is linking of heterozygous genes in repulsion. The recombination generally happens among the centromeres from the adjacent genes.
A common example of the mitotic recombination is the Bloom's syndrome. Bloom's syndrome is caused due to the mutation that occurs in the <em>blm</em> gene. As a result, there are defects in the BLM protein produced.
Answer:
Sewage facilities remove liquid and then compact solid wastes.
Explanation:
Got it right on the quiz.
I think A- laboratory mice are similar but not identical
The answer is <span>insect and pest populations decreased.
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DDT (dichlorodiphenyltrichloroethane) was used as an insecticide which is a substance used to kill insects. That resulted in decrease in insect and pest populations. It is a persistent and non-degradable insecticide, but as well organic pollutant readily accumulated to soils and consequently affects organisms.