Cell Growth and Reproduction-Meiosis

Front

What is meiosis?

Back

Meiosis is a type of cell division that reduces the chromosome number by half, resulting in four genetically diverse gametes (sperm or eggs). It consists of two rounds of division: meiosis I and meiosis II.

Front

How many chromosomes does a butterfly egg contain if a somatic cell has 24 chromosomes?

Back

12 chromosomes. In butterflies, the somatic cells are diploid (2n), while the eggs are haploid (n), so 24/2 = 12.

Front

What is crossing over and when does it occur?

Back

Crossing over is the exchange of genetic material between homologous chromosomes during prophase I of meiosis, leading to genetic variation.

Front

What happens during telophase I of meiosis?

Back

During telophase I, the cell divides into two daughter cells, each containing half the number of chromosomes (haploid), and the nuclear membrane may reform.

Front

What is the significance of metaphase I in meiosis?

Back

In metaphase I, homologous chromosomes line up at the cell's equator, which is crucial for ensuring that each daughter cell receives one chromosome from each pair.

Front

What is the difference between anaphase I and anaphase II?

Back

In anaphase I, homologous chromosomes are pulled apart to opposite poles, while in anaphase II, sister chromatids are separated.

Front

Define haploid and diploid cells.

Back

Haploid cells (n) contain one set of chromosomes, while diploid cells (2n) contain two sets of chromosomes.

Front

What is the role of spindle fibers during meiosis?

Back

Spindle fibers help separate chromosomes during cell division by attaching to the centromeres and pulling them apart.

Front

What occurs during prophase I of meiosis?

Back

During prophase I, chromosomes condense, homologous chromosomes pair up, and crossing over occurs.

Front

How many cells are produced at the end of meiosis II?

Back

Four genetically diverse haploid cells are produced at the end of meiosis II.