The mass extinctions that occurred 250 million years ago and 65 million years ago may have been due to gradual process or Catastrophic events.
Proteins.
These four carbon-based molecules are necessary for building an organism.
Relationship:
Carbohydrates and Lipids-Energy storage
Nucleic Acids - Proteins -- Blueprint - Building blocks
Answer:
SI system consist of standard units of measurement that are defined by International System Of Units.
Explanation:
SI stands for Standard International. It consist of total 7 units that are accepted internationally,
Two advantages of SI units are:
- SI unit is rational system of units, that means one unit denotes one physical quantity.
- SI units are internationally accepted which makes researchers and scientist calculations
B. trenches .......................