1. Three nucleotides encode an amino acid. Proteins are built from a basic set of 20 amino acids, but there are only four bases. Simple calculations show that a minimum of three bases is required to encode at least 20 amino acids. Genetic experiments showed that an amino acid is in fact encoded by a group of three bases, or codon.
<span>2. The code is nonoverlapping. Consider a base sequence ABCDEF. In an overlapping code, ABC specifies the first amino acid, BCD the next, CDE the next, and so on. In a nonoverlapping code, ABC designates the first amino acid, DEF the second, and so forth. Genetics experiments again established the code to be nonoverlapping. </span>
<span>3. The code has no punctuation. In principle, one base (denoted as Q) might serve as a “comma” between groups of three bases. </span>
<span>This is not the case. Rather, the sequence of bases is read sequentially from a fixed starting point, without punctuation. </span>
<span>4. The genetic code is degenerate. Some amino acids are encoded by more than one codon, inasmuch as there are 64 possible base triplets and only 20 amino acids. In fact, 61 of the 64 possible triplets specify particular amino acids and 3 triplets (called stop codons) designate the termination of translation. Thus, for most amino acids, there is more than one code word.</span>
Explanation:
40% the world doesn't have access to clean fresh water.
Answer:
independent variable and dependent variable
Explanation:
independent variable is the variable being tested and a dependent variable is the variable being measured
Answer:
The conservation of endangered species is important for humans as well. A well-balanced ecosystem purifies the environment, giving us clean air to breathe, a healthy water system to support diverse marine life, and arable land for agricultural production.
Explanation:
The health of an ecosystem is maintained by its plants and animals. When species become endangered, it is a sign of an ecosystem's imbalance. This balance is difficult to maintain: the loss of one species often triggers the loss of others. ... By saving endangered species, we are ultimately saving ourselves.
