The KT boundary marks a mass extinction event. the KT boundary is the time between the Cretaceous and Tertiary periods. An asteroid hit the earth at the end of the Cretaceous and that caused the end of the Cretaceous period. Before the KT boundary, pollen from angiosperms and gymnosperms is high. After the meteor hits the earth, a mass extinction occurs and the amount of pollen from gymnosperms and angiosperms decreases dramatically, while the amount of spores from ferns increases. During the Cretaceous period there were many species of gymnosperms and angiosperms but they disappeared at the KT boundary, when the asteroid hit the earth.
Food chains model energy flow through an ecosystem. Producers pump energy into an ecosystem from an environmental source, and this energy is then passed from one organism to the next.
Answer:
Plasma.
Explanation:
The main connective tissue of human body is blood. Blood mainly composed of the plasma and formed elements. Formed elements include white blood cell, red blood cells and platelets.
Blood plasma is present around 55% in composition. The blood plasma contains various coagulant factors, ions, proteins and chemicals. Plasma is the fluid portion of blood that needs to be drawn in presence of the anticoagulant compound.
Thus, the answer is plasma.
Answer:
B) Atoms of elements in the sun combine to release energy.
Explanation:
The process is called fusion, where atoms collide violently and release energy in the process, thus making new kinds of atoms.
