Humans have 23 pairs of chromosomes.

人类有23对染色体。

Chromosomes replicate during cell division.

染色体在细胞分裂时会复制。

Scientists studied the chromosomes of fruit flies.

科学家们研究了果蝇的染色体。

A normal human karyotype consists of 46 chromosomes.

正常人的核型由46条染色体组成。

The homologous chromosomes pair up during meiosis.

在减数分裂过程中，同源的染色体配对。

During meiosis, the number of chromosomes is halved.

在减数分裂过程中，染色体的数量减半。

The diad of chromosomes is crucial during cell division.

染色体的二联体在细胞分裂过程中至关重要。

Scientists studied the changes in chromosomes during mitosis.

科学家们研究了有丝分裂过程中染色体的变化。

Telomeres protect the ends of chromosomes, which shorten each time a cell divides.

端粒保护着染色体的末端，每次细胞分裂都会缩短。

The scientists were most interested in parts connected to the ends of the chromosomes.

科学家们最感兴趣的是与染色体末端相连的部分。