Question

1. what are homologous chromosomes?
2. what are gametes? are they haploid or diploid?

what are somatic cells? are they haploid or diploid?

1. what is the difference between haploid and diploid cells?
2. how many chromosomes do humans have in their body cells?
3. what is crossing over? when does it occur?

fill in the table to compare meiosis
meiosis
number of cell divisions
number of daughter cells
genetically identical?
chromosome #
where in body
when
role in body

Explanation:

1. Homologous chromosomes are pairs of chromosomes with the same length, centromere position, and gene - loci, one from each parent.
2. Gametes are reproductive cells (sperm and egg). They are haploid, containing half the number of chromosomes of somatic cells.
3. Somatic cells are non - reproductive body cells. They are diploid, having two sets of chromosomes.
4. Haploid cells have one set of chromosomes, while diploid cells have two sets.
5. Humans have 46 chromosomes in their body (somatic) cells.
6. Crossing over is the exchange of genetic material between homologous chromosomes. It occurs during prophase I of meiosis.

For the table comparing mitosis and meiosis:

• Number of cell divisions: Mitosis has 1 division, Meiosis has 2 divisions.
• Number of daughter cells: Mitosis produces 2 daughter cells, Meiosis produces 4 daughter cells.
• Genetically identical: Daughter cells in mitosis are genetically identical, daughter cells in meiosis are genetically different.
• Chromosome #: Daughter cells in mitosis have the same chromosome number as the parent cell (diploid), daughter cells in meiosis have half the chromosome number of the parent cell (haploid).
• Where in body: Mitosis occurs in somatic cells throughout the body, Meiosis occurs in the gonads (testes and ovaries).
• When: Mitosis occurs for growth, repair, and asexual reproduction, Meiosis occurs for sexual reproduction to produce gametes.
• Role in body: Mitosis maintains the body's cell population and tissue integrity, Meiosis is essential for genetic variation in sexual reproduction.

Answer:

1. Homologous chromosomes are pairs of chromosomes, one from each parent, with the same length, centromere position, and gene - loci.
2. Gametes are reproductive cells. They are haploid.
3. Somatic cells are non - reproductive body cells. They are diploid.
4. Haploid cells have one set of chromosomes; diploid cells have two sets.
5. Humans have 46 chromosomes in their body cells.
6. Crossing over is the exchange of genetic material between homologous chromosomes, occurring during prophase I of meiosis.

Table:

	MITOSIS	MEIOSIS
Number of daughter cells	2	4
Genetically identical?	Yes	No
Chromosome #	Diploid (same as parent)	Haploid (half of parent)
Where in body	Somatic cells throughout body	Gonads (testes and ovaries)
When	For growth, repair, asexual reproduction	For sexual reproduction to produce gametes
Role in body	Maintains cell population and tissue integrity	Essential for genetic variation in sexual reproduction