Final answer:
Sequences of amino acids are recombined to form unique protein molecules, with 20 common amino acids providing the building blocks for this diversity. A multitude of protein sequences result from the possible combinations, estimated at around 100,000,000, which are essential for life's variety and the specific functions of proteins in organisms.
Step-by-step explanation:
The sequences mentioned are recombined to create different combinations of amino acids that make up each protein molecule. The variety of sequences of the 20 common amino acids enables this diversity. Proteins are fundamental to the structure and function of all living cells and organisms. With a genetic code that uses four different nucleotides (A, C, G, and U), there is a total of 64 possible codons (3-nucleotide combinations), allowing the encoding of 20 amino acids and the necessary stop signals for protein synthesis.
Each naturally occurring protein has a unique amino acid composition and sequence, leading to distinct three-dimensional shapes and functions. The same way different words are formed using the 26-letter English alphabet, different protein sequences are formed using these amino acids. Despite there being only 20 amino acids, the possible combinations can result in an estimated 100,000,000 different protein sequences, contributing to the diversity of life.
A single gene mutation can cause a significant change in a protein's sequence, sometimes resulting in diseases like sickle cell anemia, where the substitution of just one amino acid can have detrimental effects. This highlights the critical importance of ensuring the correct sequence for protein functionality.