Lecture Notes on Genome - Fundamentals of Physiology | BMS 360, Study notes of Biology

Download Lecture Notes on Genome - Fundamentals of Physiology | BMS 360 and more Study notes Biology in PDF only on Docsity! 17 January Genome Project Started mid – 80’s Entire genome sequence of an organism Genome size Bacteria, yeast – 5,000 genes Fly – 14,000 genes Worm – 20,000 genes Human – 20-25,000 genes Chimps 98.5% identical Rice – 50,000 genes Can be used to trace evolution through amount of similarity between organisms Other human species overlapped in existence with modern humans H. sapiens sapiens: now to 200,000 years ago Central Africa H. floresiensis: 12 – 100,000? years ago H. neanderthalensis: 30 – 350,000 years ago Denisova, Siberia DNA: 40,000 years ago H. rhodesiensis: 120-300,000 years ago H. sapiens ideltu: 150-250,000 years ago Africa (200K YA), Middle East (70K YA), Europe (50K YA), Asia (50 – 70K YA), North America (12K YA) Adaptations Africa Tropical sun 300 – fold higher risk for skin cancer Dark skin, kinky hair, longer limbs Asians Siberian migration Epicanthal fold, short limbs, nose N. European Weak sun Dark skin until 6-7,000 YA Vit D, Ricketts, light skin 2-3 genes control skin color What do we mean by “race”? From Unicellular to Multicellular Dictylstelium Single, undifferentiated cell Environmental signals Cell migration Cell segregation Differentiation Each cell in the body has the same number of genes Certain genes are turned on or off – each cell expresses only a subset of its genes Epithelial, connective tissue, nerve, and muscle cells (4 types of cell)