Morgan Moritz, Noah Zhang, Shelleigh Harris, Palmer Moats Chapter 13 Part A Morgan Moritz, Noah Zhang, Shelleigh Harris, Palmer Moats

Chromosomes Chromosomes- A structure made up of nucleic acids and protein found in the nucleus, carries genetic information in your body There are 46 Chromosomes in a somatic cell Each chromosome consist of thousands of genes which make up who you are Two types of cells

Somatic Cells Somatic cells- All cells but your reproductive cells (gamete cells) Types of somatic cells Skin Liver Blood cells Tissue Lung Mussle Somatic cells have 46 chromosomes where gamete cells only have 23 because gamete cells take half of the genetic information

Gamete Cells (Reproductive Cells) Definition- Transmit genes from one generation to another reproductive cell Your gamete cells only have 23 chromosomes which is half Only have half because during fertilization the sperm and egg cell will combine to get 46 total chromosomes

Sex Chromosomes vs. Autosomes Sex chromosomes are the chromosomes that determine the individual's sex, a female is XX and a male is XY. There are only 2 sex chromosomes in each human cell. Autosomes are all the other chromosomes that aren’t sex chromosomes. They can be used to determine many different traits. There are 44 autosomes in each human cell.

Karyotype A karyotype is a display of condensed chromosomes arranged in pairs. They are prepared from isolated somatic cells, which are treated with a drug to stimulate mitosis and then grow in culture for several days. Cells arrested in metaphase, when chromosomes are most highly condensed, are stained then viewed with a microscope equipped with a digital camera, then the images of the chromosomes are arranged into pairs according to their appearance.

Purpose of Karyotyping Screen for defective chromosomes. Find abnormal number of chromosomes associated with certain congenital disorders (Down Syndrome). Abnormal positions of chromosome pieces.

Homologous Chromosomes Chromosomes that make up a pair, are the same length, centromere position, and staining pattern.

Haploid vs. Diploid Cells that only have one of each homologous pair are said to be haploid, a condition that is represented by n Cells that have two of each homologous pair are said to be diploid, or 2n Are these cells haploid or diploid? Liver cell 2n Gamete n Egg cell n Zygote 2n Skin cell 2n Sperm n Somatic cell 2n Sex cell n

Chromosomes 6 chromosomes 3 pairs 12 Chromatids Diploid!

Meiosis The union of gametes creates a fertilized cell, or zygote, which will have 46 chromosomes. Gametes are the only human cell not produced by mitosis, or else the amount of chromosomes would double every time. Instead, meiosis is a form of cell division that reduces the sets of chromosomes when producing the gametes from one to two.