BIOLOGY 1A03 Lecture Notes - Lecture 3: Monosaccharide, Streptococcus, Duodenum

• School: McMaster University
• Department: Biology
• Course: BIOLOGY 1A03
• Professor: Lovaye Kajiura

Document Summary

Lactose: a sugar common in milk and other dairy products. In infants and mammals, early development period is based on milk products. We can see this by tagging those cells (ex. Where antibody grabs onto lactase u can radiate the sample with specific wave length of tag and shows fluorescence anti body created against lactase, fluorescent tag and shows localization of lactase around edges of microvilli. Lactase production generally decreases after weaning in adult mammals other than humans, lactase production decreases significantly after weaning. ~65% of humans have reduced ability to digest lactose after weaning this is a sign that the baby is largely starting to consume other sources of nutrition in it"s diet (referring to graph on slide) Mutations that keep the lactase gene permanently on common in individuals whose ancestors had access to domesticated dairy animals (inherited as dominant trait) Cows domesticated between 7500-9000 years ago in middle east and north.