Answer:
A. body muscles
The pressure needed to pump blood back to the heart is produced by the <u>body </u><u>muscles </u><u>.</u>
Im pretty sure it weight because when we are on different plants with a different amount of gravitational pull our weight changes
hope this helps :)
Answer:
100 teragrams of nitrogen per year
Explanation:
Nitrogen fixation in Earth's ecosystems is defined as a process where by nitrogen in air is transformed into ammonia or other related nitrogenous compounds. Generally, atmospheric nitrogen is referred to as molecular dinitrogen and it is a nonreactive compound that is metabolically useless to all but a few microorganisms. This process is vital to life due to the fact that inorganic nitrogen compounds are needed for the biosynthesis of amino acids, protein, and all other nitrogen-containing organic compounds. Thus, the natural rate of nitrogen fixation in Earth's ecosystems is 100 tetragrams of nitrogen per year.
There are three types of artificial cloning:
Gene cloning: copies a few segments of DNA or genes.
Reproductive cloning: it copies the whole animal.
Therapeutic cloning: produces embryonic stem cells for experiments aimed at creating tissues to replace injured or diseased tissues.
