Title: אופציונלי

Text: Why is recycling carbon important? Recall that carbon is the cornerstone of organic compounds, the compounds necessary for life. But do organisms make their own carbon? Do they have the genes that encode proteins necessary to make carbon? No. In fact, there are no such genes. Carbon must be recycled from other living organisms, from carbon in the atmosphere and from carbon in other parts of the biosphere. כל פסקה תהיה מבחן.

Save test: השתמש בזה אם אתה רוצה לשתף את המבחן הזה בהקלדה (רק למשתמשים מאומתים).