As we all know the genetic code is essentially the same for all organisms. So, from this, one can logically assume which of the following?
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From this, one can logically assume which of the following?
The genetic code is essentially the same for all organisms. From this, one can logically assume which of the following is right?
- A gene from an organism can theoretically be expressed by any other organism.
- DNA was the first genetic material.
- Different organisms have different types of amino acids.
- The same codons in different organisms translate into different amino acids.
- Below are the answer and explanations.
Genetic code
The genetic code is a set of rules that translates DNA or RNA sequences into amino acid sequences of proteins in groups of three nucleotides for protein synthesis.
It determines the order of synthesis of each amino acid and each amino acid in the peptide chain, as well as the initiation, extension, and termination of protein synthesis.
The genetic code, also known as a codon, genetic codon, and triplet code, harbors the secrets of life and its historical evolution.
The genetic code is the set of rules used by living cells to translate information about genetic material encoded in DNA or mRNA sequences into proteins.
Translation of mRNA is accomplished through the ribosome. The ribosome uses a transfer RNA (tRNA) molecule to read three nucleotides of mRNA at a time and join the amino acids it encodes in the order specified by the messenger RNA (mRNA) to complete the synthesis of the protein polypeptide chain.
Since only one single strand (called the template strand) of DNA, duplex is generally transcribed as messenger RNA (mRNA). The other single strand (called the coding strand) is not transcribed.
Therefore, even for organisms with double-stranded DNA as the genetic material, the code is expressed in terms of the nucleotide order in ribonucleic acid (RNA) rather than in terms of the deoxyribonucleotide order in DNA.
The genetic code determines the nucleotide order of amino acids in proteins and consists of three consecutive nucleotide codons.
The genetic code is highly similar in all organisms, and almost all organisms use the same genetic code, which can be expressed in a codon table containing 64 entries. Even viruses with non-cellular structures use the standard genetic code. However, there are a few organisms that use a slightly different genetic code.
Amino acids
Amino acids, organic compounds containing basic amino and acidic carboxyl groups, have the chemical formula RCHNH2COOH. compounds formed when the hydrogen atom on the carbon atom of a carboxylic acid is replaced by an amino group.
Amino acids can perform some of the following roles in the human body through metabolism.
- Synthesis of tissue proteins
- transformation into ammonia-containing substances such as acids, hormones, antibodies, and creatine
- Transformation into carbohydrates and fats
- Oxidation to carbon dioxide and water and urea, producing energy
Amino acids are colorless crystals with a melting point of over 200°C, which is much higher than the melting point of organic compounds in general.
Alpha-amino acids have 4 different taste sensations: sour, sweet, bitter, and fresh. Monosodium glutamate and glycine are the most used fresh flavoring ingredients.
Amino acids are generally soluble in water, acid solutions, and alkali solutions, and insoluble or slightly soluble in organic solvents such as ethanol or ether.
The solubility of amino acids in water varies greatly. For example, the solubility of tyrosine is the smallest, at 25℃, tyrosine dissolves only 0.045g in 100g of water. However, the solubility of tyrosine is greater in hot water.
Lysine and arginine often exist in the form of hydrochloride, because they are very soluble in water and difficult to make crystals due to deliquescence
Codons, groups of three nucleotides compiled for each adjacent nucleotide in an RNA molecule, represent a particular amino acid during protein synthesis.
Scientists have discovered that messenger RNA can determine the type and order of amino acids in a protein molecule in a cell. That is, the sequence of four nucleotides (bases) in a messenger RNA molecule can determine the sequence of 20 amino acids in a protein molecule.
What is the correspondence between the number of bases and the type and number of amino acids?
To determine this relationship, the researchers added a messenger RNA molecule with 120 bases and everything needed to synthesize the protein to the test tube. The result was a polypeptide molecule containing 40 amino acids.
This shows that three bases on a messenger RNA molecule can determine an amino acid.
Essential amino acids
Essential amino acids are amino acids that cannot be synthesized in humans or other vertebrates or are synthesized at a rate that is far from adequate for the needs of the body and must be supplied by dietary protein.
The requirement of essential amino acids for adults is about 20% to 37% of the protein requirement.
Correct Answer
As the genetic code is essentially the same for all organisms. We can learn the correct answer to From this, one can logically assume which of the following?
- A. A gene from an organism can theoretically be expressed by any other organism.
As the genetic code is essentially the same for all organisms. Therefore, a gene from an organism can theoretically be expressed by any other organism.
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