The right answer is C. I think, a. and d. are obviously not serious. B is not true, because Ag and Au are in the same group in the periodic table and therefore have the same number of electrons in the last level. So, they form ions with the same charge. C is true beacause Ag and Au have different numbers in the periodic table and different amount of protons and neutrons in their nucleuses.
The best answer is B.
The endosymbiotic theory states that mitochondria and chloroplasts have striking similarities to bacterial cells:
1. they have their own DNA, which is separate from the DNA found in the nucleus of the cell.
2. Both organelles use their DNA for to produce many proteins and enzymes required for function.
3. They are both surrounded by a double membrane.
4. They reproduce just the way bacteria do, replicating their own DNA and directing their own division.
Answer:
C. They break down food materials into forms the cell can use.
Direct observation is an observation you make first hand. It is something you see with your own eyes and observe yourself.
Hope this helps!
The ocean animals deposited in it's layers
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