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 .
Answer:
Maintain homeostasis.
Explanation:
Homeostasis is the ability to maintain a stable internal state. All organisms need to maintain homeostasis and must regulate their internal environment to process energy and stay alive. Rubbing your arms and shivering is your body's natural response to getting colder and trying to warm up. The students body is responding to the cold environment in order to maintain homeostasis - in this case the proper body temperature of 98.6°F or 37°C.
No, the correct answer is Ecosystem
Answer:
B
Explanation:
Radiometric dating uses naturally occurring radioactive elements such as carbon-14 within the rock or fossil to estimate its approximate age. The half-life of the element must also be known. The amount of the radioactive trace element is compared to, in a ratio, with that of the number of the decay product elements. This approximate age can then be relatively compared to those of other rocks or fossils.