Life as we know it depends on the genetic code: a set of codons, each made up of three bases in a dna sequence and corresponding mrna sequence, that specifies which of the 20 amino acids will be added to the protein during translation. imagine that a prokaryote-like organism has been discovered in the polar ice on mars. interestingly, these martian organisms use the same dna → rna → protein system as life on earth, except thatthere are only 2 bases (a and t) in the martian dna, andthere are only 17 amino acids found in martian proteins. based on this information, what is the minimum size of a codon for these hypothetical martian life-forms?

The right answer is 5.

To answer this question, we must think in the same way as the demonstration showing that codons of 3 are necessary to encode an amino acid (in terrestrial species).

To calculate the number of nucleotides in a codon in these new species: we should use the law of:

nucleotides existing ^ (number of nucleotides in a codon) = number of codons.  (in order to have the number of possible codon combinations)

The number of codons must be greater than or equal to the number of amino acids (17).

2 ^ 1 = 2 (<17)

2 ^ 2 = 4 (<17)

2 ^ 3 = 8 (<17)

2 ^ 4 = 16 (<17)

2 ^ 5 = 32  (> 17)

32> 17 so the number of nulceotides in a codon must be 5.

q: compare the parts of a cell and the cell as a whole to another common nonliving system (i.e., a car, a city,

a:

comparing this to the inside of a food building/company.

all cells are surrounded by a plasma membrane, which protects the cell from its environment, keeping toxic substances out of the cell. it regulates which molecules are allowed to enter and exit the cell.

regulates all cell activity such as cellular metabolism, and growth in addition to storing and maintaining the cell's dna for transcription and replication. determines what proteins to make.

contains the organelles; site of most cell activity

the place where ribosomes do their working activity.

builds the proteins.

prepares proteins for use or export.

responsible for breaking down and absorbing materials taken in by the cell.

maintains cell shape.

transforms one form of energy into another.

this age may represent the age of the earth's accretion, of core formation, or of the material from which the earth formed. this dating is based on evidence from radiometric age-dating of meteorite material and is consistent with the radiometric ages of the oldest-known terrestrial and lunar samples.