Answer:
B) The first shell only holds 2 electrons so the 3rd electron had to go in the second shell.
Explanation:
Electrons fill up from smallest to largest, the first electron shell only holds 2 electrons, so the remaining electron had to go to the second shell.
Answer: 1) Adenine pairs with thymine, cytosine pairs with guanine
Explanation: Here’s a helpful tip ;) Think of it as apples to trees, cars to garage. Apples being adenine, trees being thymine. Cars being cytosine and garage being guanine.
Answer:
<u>C) They may provide selective advantages.
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<u>D) Slight differences in the genetic code may have significant results.</u>
Explanation:
The genetic code is universal, and present in most living beings . Generally, in most living organisms, the same codons are assigned to the same amino acids.
DNA sequences make up genes that may have multiple variants, called alleles. DNA deoxyribonucleic acid, is transcribed into mRNA and then translated into amino acids that form proteins.
Natural selection mainly acts on phenotypes, which are dependent on proteins and the organisms's environment. Phenotypes conferring advantageous traits are favored by the selection process- these help groups of organisms evolve over time.