PS275 Study Guide - Midterm Guide: Xyy Syndrome, Unit, Y Chromosome
Document Summary
Call for production of amino acids which form enzymes and other proteins necessary for formation and functioning of new cells. Guide cell differentiation, regulate pace and timing of development. Zygote = replicates itself/its 46 chromosomes through mitosis. Crossing over = genetic material exchanged between chromosome pairs during meosis, creates new and unique hereditary combos. Monozygotic twins: developed from single zygote, identical genes, zygote splits into 2 cells. Dizygotic twins: mother releases 2 ova at same time, each fertilized by different sperm. The 22 out of 23 pairs of chromosomes that are similar in males and females. Female pair = both xs, males = x and y. Half of sperm produced by males contain x chromosome, other half y, child"s sex depends on whether. X bearing or y bearing sperm fertilizes ovum. Alleles: pair of genes, one from each parent, appear at a particular site on a chromosome. One allele dominates another, only its phenotype is expressed.
