Answer:
A system that uses the sun's energy without requiring mechanical devices (pumps or fans) to distribute the collected heat are called solar system while radiator system uses fuel to heat the water. in active solar heating system, the SUN's energy used to heat water.
Answer: gastrula, archenteron, blastospore
Explanation:
a) Gastrulation is a dramatic reorganization of the hollow blastula into a two-layered or three-layered embryo called a gastrula.
b) Invagination of cells into the blastocoel forms a tube called the archenteron.
c) The open end of the archenteron is called the blastospore..
The awnser to this question is Absorption
