Welcome! Monday, 1/14 Gametes – sperm and egg are gametes Gene – A section of DNA that codes for a protein Chromosome – Visable DNA Chromatids – two exact copies of a chromosome Centromere – Where chromatids join
TOC • 1. Reviewing terms from book 1/8 • 2. Probability 1/8 • 3 Mitosis/Meiosis 1/11 • 4 Meiosis Notes
Somatic Cell – any cell in the body other than gametesHuman somatic cells have a total of 46 chromosomes or 23pairs.
Homologous Chromosomes – similar size, shape, and genetic contentDiploid – two sets of chromsomesdiploid number in a human somatic cell can be written as: 2n=46Haploid – one set of chromsomeshaploid number in a human gamete can be written as: n=23
Zygote – fertilized eggFertilization – uniting of sperm and eggautosomes – any of the chromosomes not used in determining sexOf the 23 pairs of chromosomes, how many pairs are autosomes? 22
Male: XY Female: XXUltimately, the sex of the child is determined by the male.
Meiosis – form of division that results in half of the chromosomesCrossing over – breaking/joining and remixing of homologous chromosomesIndependent assortment -is the random assortment of chromosomes during the production of gametes
Random fertilization: The ovum has 8 million possible chromosome combinations, so does the sperm cell. 8 million x 8 million = 64 trillion possible diploid combinations in EACH AND EVERY zygote! WOW!!In other words, you're unique...(...just like everyone else.....).
Spermatogenesis – process that makes spermssperm – a male gamete used in reproductionOogenesis - The formation, development, and maturation of an ovum – a mature eggPolar body - minute cell produced and ultimately discarded in the development of an oocyte
Life cycleParthenogenesis - is type of asexual reproduction in which a female gamete or egg cell develops into an individual without fertilization