House sparrows in the northern part of North America are larger than those found in the southern regions. The possible mechanism of microevolution is more likely to be responsible for this is natural selection. The answer would be letter B.
Surface tension decreases when temperature increases because cohesive forces decrease with an increase of molecular thermal activity
Answer:
Following are the salient adaptations of villi that make them good absorbers:
Villi are single cell thick. ...
Villi have rich network of blood capillaries . ...
Most important is: Apical membranes of Villi further form many finger-like projections called microvilli or brush borders. ...
Villi have permeable membranes .
Parasitism; the tick benefits from the human, the host.
