Question

Each chromosome is made of a single chromatin fiber. Different organisms have different numbers of chromosomes in their cells. Most human body cells contain 46 chromosomes—23 inherited from one parent, and 23 inherited from the other. Each of the 23 pairs of chromosomes contains different genes. For example, a gene found on chromosome 9 produces a protein that determines whether a person will have type A, B, AB, or O blood.

Complete the paragraph.
A chromosome is composed of one tightly folded
. Human body cells contain
pairs of chromosomes; most other species have
number of chromosomes in their cells. Each chromosome pair within a cell has
the other chromosome pairs.

Answer 1

A chromosome is composed of one tightly folded chromatin fiber. Human body cells contain 23 pairs of chromosomes; most other species have a different number of chromosomes in their cells. Each chromosome pair within a cell has different genes from the other chromosome pairs.