The answer is:
The gravity acceleration is in the same direction as the force of gravity, and thus toward the center of the earth.
The approximately number of earths surface is covered by land is 29 percent
Question is incomplete, the complete question is as follows :
Clotting begins when a _________ occurs in a blood vessel wall. Almost immediately, _______ cling to the blood vessel wall and release _____________ which helps to decrease blood loss by constricting the vessel. __________ is also released by damaged cells in the area. This chemical substance causes ________to be converted to ____________. Once present, thrombin acts as an enzyme to atatch ___________molecules together to form long, threadlike strands of _________, which then traps ____________ flowing by in the blood.
Answer:
Clotting begins when a <u>BREAK</u> occurs in a blood vessel wall. Almost immediately, <u>PLATELETS</u> cling to the blood vessel wall and release <u>SEROTONIN</u>, which helps to decrease blood loss by constricting the vessel. <u>THROMBOPLASTIN</u> is also released by damaged cells in the area. This chemical substance causes <u>PROTHROMBIN</u> to be converted to <u>THROMBIN</u>. Once present, thrombin acts as an enzyme to attach <u>FIBRINOGEN</u> molecules together to form long, threadlike strands of <u>FIBRIN</u>, which then traps<u> ERYTHROCYTES </u>flowing by in the blood.
The Immune system and Endocrine system work
together to remove these wastes from their cells.