Answer:
False. There are 20 amino acids, but 64 possible codons.
Explanation:
Genetic information for the aminoacids assembly during the protein synthesis is stored in short sequences of three nucleotides named codons in the mRNA. Each of the codons represents one of the 20 amino acids used to build the protein. The total number of possible codons is 64, from which 61 codify amino acids -more than one codon codify for the same amino acid-. One of these amino acids is also the start point of protein synthesis. And the left three codons are stopping translation points.
The codons indicating the initiation or stop points during the translation process are:
• The start codon AUG is the most common sequence used by eukaryotic cells and places near the 5´extreme of the molecule. However, other codons might be used as well. Prokaryote cells might use the codons GUG or UUG.
• The end codons are UAA, UAG, UGA.
Answer: Hydrosphere is the total mass of water found on the Earth's surface. Atmosphere is the layer of air that envelopes the Earth. Hydrosphere consists of lakes, oceans, rivers, seas, water vapours, underground water and ice sheets of the mountainous regions.
Explanation:
Answer:
Variability was seen as imperfection, so natural selection could only eliminate the inferior and imperfect, not giving rise to new things, new species.
:
Answer: Y goes to proteins.
Explanation:
Enzymes, which are a form of protein, are used by the cell to accelerate chemical reactions.
Answer:
Lichens are not parasitic when they grow on trees, they just use the tree bark as a home. They enrich the soil by trapping water, dust and silt. When lichens die they contribute organic matter to the soil, improving the soil so that other plants can grow there.