A Chromosome Study

Karyotype Prepare a karyotype of the chromosomes provided. Karyotype: a pattern or picture of chromosomes from one cell grouped into pairs and organized by size Pair up each chromosome with its homologous partner, using the size and markings to determine pairs. On a blank paper, arrange the chromosome pairs from largest to smallest and number them (from 1-22). Put the sex chromosomes last (this is pair 23). Glue or tape the chromosomes to the paper in the correct order.

Analysis How many total chromosomes are present in this karyotype? How many chromosomes are present in each cell of this human? 46 46

Analysis Does your karyotype represent a male or a female? Female: two X chromosomes Male: an X chromosome and a Y chromosome

Analysis Chromosomes that are NOT sex chromosomes are called autosomes. How many total autosomes are present in your normal karyotype? 44 (22 pairs)

Diploid number Body cells are somatic cells: including skin, liver, muscle cells, etc. Diploid number=number of chromosomes in a somatic cell Varies from species to species 2n What is the diploid number for your karyotype? 46

Haploid number Refers to the number of chromosomes in an organism’s sex cells (sperm and egg cells) Half the diploid number 1n What would the haploid chromosome number for your karyotype be? 23

Chromosome # in somatic cells (2n) Chromosome # in gametes (n) Species Chromosome # in somatic cells (2n) Chromosome # in gametes (n) Human 46 23 Fruit Fly 8 Chicken 39 Goat 30 4 78 60

male 40 20 Is this rat male or female? How many chromosomes would be found in skin cells? How many chromosomes are found in the sperm cells from this organism? male 40 20