Which advantages does the skeleton of birds provide for flight?
a. light hollow bones
b. volume and heavy weight for lift
c. rigid structure to anchor strong muscles for flight
d. loosely unconnected bones

Which statements describe resources? one of the factors people use when deciding where they will live is the availability of resources. renewable resources have little value for people. resources are unevenly distributed throughout the world. energy is the world resource which has the highest use. the use of nonrenewable resources has decreased in recent history. the use of resources is evenly distributed throughout the world. the world's oil supply will last for the next forty years if its use continues as expected.

Which event would lead to primary succession of a forest?

Explain how sequences of amino acids in proteins can be used to reveal relationships among organisms.