100 likes | 145 Views
Learn about chromosomes, genetic disorders, and characteristics such as Down's syndrome, Turner's syndrome, and Klinefelter's syndrome. Discover how chromosomes impact human genetics and how mutations manifest in different disorders.
E N D
Characteristics • Chromosomes are long, threadlike groups of genes made up of DNA; found in the nucleus. • Chromosomes are always an even number Examples: Humans – 46 Dogs – 78 Mosquitoes – 6 Goldfish – 94 • Each chromosome has many genes on it!
Human Chromosomes • Each person has 46 chromosomes • (23 from your mom and 23 from your dad) 1. Autosomes – first 22 pairs (44 total) 2. Sex Chromosomes – 23rd pair (2 total) XX = female XY = male
Amniocentesis • One way to detect genetic defects is to obtain fetal cells through a needle inserted in the amniotic sac of a pregnant woman.
Karyotype • A method of organizing the chromosomes of a cell in relation to size. • It is a tool used to help detect genetic defects
Mutations • Down’s syndrome – extra #21 chromosome; mental deficiencies, short stature, short wide neck, stocky arms and legs, sterile. • Turner’s syndrome – XO (female’s with only one X) they are shorter than normal. • Klinefleter’s syndrome – XXY (male’s with an extra X chromosome) they are taller than normal. • Cri-du-chat (French for Cry of the Cat). Missing part of chromosome #5. When babies are born with this they sound like a cat crying. Downward slant to the eyes, Low birth weight, mental deficiencies, Skin tags just in front of the ear, small head, small jaw, Wide-set eyes
What disorder?Male or female? • Cri-du chat
What disorder?Male or female? • Down’s syndrome • Female
What disorderMale or female? Turner’s syndrome Female Sisters….one with Turner’s syndrome
What disorder?Male or female? • Kleinfelter’s Syndrome • male