As microscope technology improved over time, the magnification became advanced enough to discover cells in the 17th century. this discovery is largely attributed to robert hooke, and began the scientific study of cells, also known as cell biology. over a century later, debate continued among scientists about how cells began. most of these debates involved the nature of cell reproduction, and the idea of cells as a fundamental unit of life. cell theory was eventually formulated in 1839. the three tenets to the cell theory are as described below: 1. all living organisms are composed of one or more cells. 2. the cell is the basic unit of structure and organization in organisms. 3. cells arise from pre-existing cells. how does cell division prove the cell theory? a) cell division demonstrates spontaneous generation. b) cell division demonstrates that cells come from preexisting cells. c) cell division demonstrates that all living organisms are composed of one or more cells. d) cell division demonstrates that the cell is the basic unit of structure and organization in organisms.

Answer B) Cell division demonstrates that cells come from pre existing cells.

The correct answer will be option-B.

Explanation:

Cell division is the process which divides a parent cell to daughter cells through sequential steps as a part of the cell cycle. The cell division takes place in two phases: Karyokinesis- the division of nuclear material and the cytokinesis- the division of the cytoplasm.

The cell division proves one aspect of the cell theory proposed by Rudolf Virchow that is cells arises from the pre-existing cells as the pre-existing cell divides to form the daughter cells through cell division.

Thus, Option-B is the correct answer.

transcription is a process in which information is rewritten. it is something our cells must do, in a more specialized and narrowly defined way. in biology, transcription is the process of copying out the dna sequence of a gene in the similar alphabet of rna. it needs to happen in the nucleus because that's where the dna is. dna is always inside the nucleus unless the cell is dividing.

transcription is the first step in gene expression, which involves copying a gene's dna sequence to make an rna molecule. transcription is performed by rna polymerases. it has three stages: initiation, elongation, and termination. rna molecules must be processed after transcription in eukaryotes.

explanation:

long version:

the protein synthesis consists two processes which are, transcription and translation. transcription takes place in the nucleus. it uses dna as a template to make an rna molecule. rna then leaves the nucleus and goes to a ribosome in the cytoplasm, where translation occurs. transcription is the first part of the central dogma of molecular biology: dna → rna. it is the transfer of genetic instructions in dna to messenger rna (mrna). during transcription, a strand of mrna is made that is complementary to a strand of dna.  

these three stages are:

  initiation: in which   is the beginning of transcription.occuring when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

    elongation: in which is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

    termination: in which is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.