How do scientists know when life began?

Scientists have used genes from spiders to genetically engineer goats that produce silk strands along with their milk. Which of the following is true of the silk made by the goats?

How do you determine accuracy?!!

Many deciduous trees have leaves which turn yellow in the fall. what do you suppose is happening in the leaves at the cellular and molecular level? 4.

What does the metamorphosis of a frog involve?

8. Explain how cells move large particles into the cell by endocytosis.

Which of the following scenarios describes an epistatic gene interaction?

An 1815 volcanic eruption in Indonesia was followed by a three-year famine around the world. How was the volcano linked to the famine? O A. The eruption's ash and gas significantly dimmed the sun. B.

In the general equation of photosynthesis, why is chlorophyll written over the arrow rather than on the left side of the equation'

How many years did the Precambrian Era span? 2.5 billion 5 million 5,000 none of the above

Explain why most quartz is useful?