I believe the blank is "mass."
<span> After fertilization, the </span>zygote<span> undergoes cleavage to form the blastula. The blastula, which in some species is a hollow ball of cells, undergoes a process called gastrulation, in which the three germ layers form.</span>
Answer:
The grasshopper doesn't have to use it circulatory system to carry gases to and from the grasshopper cells because the air that is passed through the trachea system is already close enough to get to the cells.
Explanation:
"In the grasshopper, exchange of oxygen and carbon dioxide occurs in the tracheal system. Hemolymph plays no part in the process. There is not even an oxygen-carrying pigment in insect hemolymph." - www.biology-pages.info
(Here's some extra info as well)
<h2>Answer:</h2>
Mesosphere
<h2>Explanation:</h2>
The atmospheric layer that protects the Earth against danger of the rocks is the mesosphere. This layer is above the stratosphere. The temperature drops in this layer to about -100 degrees Celsius. This is the coldest region of the atmosphere. The mesosphere burns up most meteors and asteroids before they are able to reach the earth's surface. It becomes cold enough to freeze water vapor in its atmosphere into ice clouds.
Any property that is measurable, whose value describes a state of a physical system.
