Questions: L. lactis bacteria may live on plants or in milk. These two environments contain different types or sugars. Plants contain polysaccharides but not lactose. Milk contains lactose but not polysaccharides. L. lactis are often best adapted to fermenting the sugar in their environment. So, L. lactis living on plants often have polysaccharide-specific fermentation, and L. lactis living in milk often have lactose-specific fermentation. Consider the population of L. lactis bacteria over the time period previously shown. Over this time period, bacteria with polysaccharide-specific fermentation were less likely to survive and reproduce than bacteria with lactose-specific fermentation. This means that having polysaccharide-specific fermentation was less advantageous than having lactose-specific fermentation.

Transcript text: L. lactis bacteria may live on plants or in milk. These two environments contain different types or sugars. Plants contain polysaccharides but not lactose. Milk contains lactose but not polysaccharides. L. lactis are often best adapted to fermenting the sugar in their environment. So, L. lactis living on plants often have polysaccharide-specific fermentation, and L. lactis living in milk often have lactose-specific fermentation. Consider the population of L. lactis bacteria over the time period previously shown. Over this time period, bacteria with polysaccharide-specific fermentation were less likely to survive and reproduce than bacteria with lactose-specific fermentation. This means that having polysaccharide-specific fermentation was less advantageous than having lactose-specific fermentation.