FRQ 01 / 099 points total
Natural SelectionChange
Milk Components and Evolutionary Relationships
Mammalian milk contains antibodies produced by the mother's immune system and passed to offspring during feeding. Milk also contains a sugar (lactose) and may contain proteins (protein A, protein B, and casein), as shown in the table.
MILK COMPONENTS IN DIFFERENT MAMMALS
| Character | Cat | Cow | Horse | Human | Pig |
|---|---|---|---|---|---|
| Lactose | + | + | + | + | + |
| Protein A | + | + | + | + | + |
| Protein B | - | + | + | - | + |
| Casein | - | + | + | - | + |
+ indicates presence of the character, - indicates absence
(a)Using the data, construct a cladogram on the template and indicate where each character most likely arose. Justify the placement of the characters. [3 pts]
(b)Describe FOUR steps in the activation of the mother's specific immune response following exposure to a bacterial pathogen. [4 pts]
(c)Predict the most likely consequence for a nursing infant exposed to an intestinal bacterial pathogen that the mother encountered three months earlier. Justify your prediction. [2 pts]