The two are potassium and rubidium. Why? Na is an alkali metal. As you go down the metals become more reactive.
Calcium has 20 protons. Why? The atomic # is 20 (the one at the top).
It has 20 neutrons. Why? The atomic mass (the number on the bottom) is ~40, ignoring electron mass. 40- 20 protons = 20 neutrons.
It has 20 electrons.
Why? The # of protons and electrons is the same. Ions aren't on the periodic table.
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About the geologic time scale divisions
The geologic history of the Earth is broken up into hierarchical chunks of time. From largest to smallest, this hierarchy includes eons, eras, periods, epochs, and ages.
Feces are deposited on the ground, and the bacteria in the soil breaks it down, and uses the nutrients
Answer:
tertiary structure
Interactions among the amino acid side chains within a single protein molecule determine the protein's tertiary structure. Tertiary structure is the most important of the structural levels in determining, for example, the enzymatic activity of a protein.
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The disorder where the grandfather and the grandchild are affected is related with the X chromosome and is called Sex linked or X linked disorder.
<h3><u>Explanation:</u></h3>
All the sex linked disorders are recessive in character i.e the normal allele is dominant over the mutated allele. In females, there are 2 X chromosomes, so the mutated allele is only expressed when there are both the mutated alleles, else its masked by the dominant normal allele. But in males, there's only one X chromosome, so if a mutated allele is present, it's readily expressed.
If the Grandfather is diseased, then he must have that mutated allele in X chromosome. Through reproduction, its received by the mother, but she is normal because the other allele received from grandmother was normal. But mother has one of the X chromosomes with mutated allele, which is received by the grandson who again becomes diseased.
So the disorder must be X linked disorder
