Question

if a human has an extra copy of one pair of homologous chromosomes, how many chromosomes will she have in total? enter the answer

Explanation:

Step1: State normal human chromosome count

A typical human has 46 chromosomes, or 23 homologous pairs.
$$46 = 23 \times 2$$

Step2: Add extra chromosome copy

An extra copy of one homologous pair means adding 1 chromosome to the total.
$$46 + 1 = 47$$

Answer:

47