It was A. I also do pacyber!
The right answer is B and C.
For proposal C, I will give you an example, that of an autosomal recessive disease. If a parent is heterozygous for an allele causing an autosomal recessive disease (due to a mutation), it may be that it transmits the allele to its descendence, as it may not be able to transmit it (since in one heterozygous subject, not all of its gametes carry the mutated allele) and thus the mutation will no longer be copied through the generaitons.
Each individual is genetically unique. Its genes are distributed along chromosomes contained in the nucleus. Mutations can lead to the appearance of different versions of genes: alleles. A diploid individual has two copies of each gene, which may be identical or different alleles. Mixing during sexual reproduction partly explains the genetic diversity of individuals.
Answer:
Once a vital plant that many humans or animals need go extinct, many of them will die due to starvation and or shelters they build might not be able to be built due to the extinct plant being gone. As an example, If trees went extinct, humans wouldn't be able to live. One, because trees help filter the air for us humans to breath, wood is a very vital supply too. Wood is used for paper, homes, and even appliances.
Explanation:
No a scientific method is not used to to prove anything.
They can exchange both matter and energy, exchange energy but not matter, Isolated systems can exchange neither energy nor matter.
In a closed system only energy can be exchanged; matter stays inside.
In a open system matter and energy can be exchanged