Question

directions: answer the following questions.

1. what is the purpose of meiosis?
2. what is the difference between an autosome and a sex chromosome?
3. is the cell that results from fertilization diploid or haploid? explain.
4. does mitosis or meiosis occur more frequently in your body? explain your answer.
5. do you think the y chromosome contains genes that are critical for an organism’s survival? explain your reasoning.
6. how do homologous chromosomes differ from sister chromatids?
7. how many autosomes are in the human karyotype below?
8. how many sex chromosomes are in this karyotype?
9. based on the image, is this a karyotype of a diploid or haploid cell? explain.
10. based on this karyotype, what is the biological sex of this individual? how do you know?

Explanation:

1. Meiosis is a type of cell - division that produces four genetically diverse haploid gametes (sperm and eggs) for sexual reproduction. This genetic diversity is crucial for evolution and adaptation.
2. Autosomes are non - sex chromosomes and are identical in both males and females in a species. Sex chromosomes determine the biological sex of an individual (e.g., XX in females and XY in males in humans).
3. The cell resulting from fertilization is diploid. Fertilization is the fusion of a haploid sperm and a haploid egg, combining their genetic material to form a cell with two sets of chromosomes (diploid).
4. Mitosis occurs more frequently in the body. Mitosis is involved in growth, repair, and asexual reproduction of somatic cells. Meiosis is specific to the production of gametes in the reproductive organs and occurs less often.
5. The Y chromosome does not contain genes critical for an organism's survival. Females, who lack a Y chromosome, are fully viable. The Y chromosome mainly contains genes related to male - specific development, like the SRY gene for testis development.
6. Homologous chromosomes are pairs of chromosomes (one from each parent) that have the same genes at the same loci but may have different alleles. Sister chromatids are identical copies of a single chromosome formed during DNA replication and are held together by a centromere.
7. In a human karyotype, there are 44 autosomes. Humans have 23 pairs of chromosomes, and 22 of those pairs are autosomes.
8. There are 2 sex chromosomes in a human karyotype (either XX or XY).
9. This is a diploid karyotype. Diploid cells have two sets of chromosomes, and the karyotype shows pairs of chromosomes.
10. The biological sex is male. The presence of one X and one Y sex chromosome in the karyotype indicates male biological sex.

Answer:

1. To produce four genetically diverse, haploid gametes (sperm and eggs) for sexual reproduction.
2. Autosomes are non - sex chromosomes, identical in males and females; sex chromosomes determine biological sex.
3. Diploid; formed by fusion of haploid sperm and egg.
4. Mitosis; involved in growth, repair of somatic cells.
5. No; females without Y are viable, Y has male - specific genes.
6. Homologous chromosomes are pairs from parents with same genes but different alleles; sister chromatids are identical copies of a chromosome.
7. 44
8. 2
9. Diploid; shows pairs of chromosomes.
10. Male; presence of X and Y sex chromosomes.