Question

1. a scientist develops a model showing transfer of genetic information.

based on the model, how is the genetic information transferred to daughter cells?
a the genetic material is copied once and divided once, producing daughter cells with the same number of chromosomes as the parent cell.
b the genetic material is copied once and divided twice, producing daughter cells with half the number of chromosomes as the parent cell.
c the genetic material is copied twice and divided twice, producing daughter cells with the same number of chromosomes as the parent cell.
d the genetic material is copied twice and divided twice, producing daughter cells with double the number of chromosomes as the parent cell.

Explanation:

This question is about cell division. In meiosis (which is what the model likely represents as the chromosome number is halved in daughter cells compared to the parent cell), the genetic material (DNA) is replicated (copied) once during the S - phase of interphase before meiosis begins. Then, there are two rounds of division: meiosis I (homologous chromosomes separate) and meiosis II (sister chromatids separate). As a result, the daughter cells (gametes in many organisms) have half the number of chromosomes as the parent cell.

• Option A: If the genetic material is copied once and divided once, it would be mitosis (producing daughter cells with the same chromosome number as the parent cell), but the model shows a halving of chromosome number, so this is incorrect.
• Option B: Matches the process of meiosis (copy once, divide twice, daughter cells with half the chromosome number).
• Option C: Copying twice is not part of the normal meiosis or mitosis process. In meiosis, DNA is copied once.
• Option D: Copying twice is incorrect, and the daughter cells have half, not double, the chromosome number of the parent cell.

Answer:

B. The genetic material is copied once and divided twice, producing daughter cells with half the number of chromosomes as the parent cell.