Mitosis is the process of cell division, where one parent cell divides to produce two genetically identical daughter cells. This process is vital in growth and tissue repair.
The reason that tissue from the fetal stage is helpful in studying mitosis is because mitosis is continuously and rapidly occurring in this phase of life in humans. The high rate of mitosis is due to the need for the fetus to grow rapidly and develop the necessary parts for it to be born.
Answer:
The correct answer will be option-A and B.
Explanation:
Transcription is a process which synthesizes a complementary molecule of DNA which acts a messenger called RNA.
The gene contains a sequence of the nucleotide at the beginning of gene called promoter sequence. The promoter sequence has the ability to attach an RNA synthesizing enzyme called RNA polymerase.
The RNA polymerase is the enzyme which synthesizes the RNA molecules using a single strand of DNA called template strand. RNA polymerase binds nucleotide at 3' end of the strand thus proceeding the strand in 5' to 3' direction.
The promoter and RNA polymerase begins the process of transcription and thus option-A and B is the correct answer.
The generalization that all organisms are composed of cells was established through multiple observations in various kinds of animals and plants. A controlled experiment of finding cells in all the kinds of living organisms is not possible or is infeasible as it will require prior knowledge of all the kinds of organisms inhabiting Earth and the effort to catch and bring them in the controlled environment of the lab for testing.
The correct answer is B. Natural selection occurs through generations and is in which organisms best suited to their environment survive.