The 3 checkpoints include G1 where the cell growth is checked, G2 where the integrity of the DNA/chromosome is checked, and M where the integrity of the metaphase plate is checked.
<h3>Cell cycle checkpoints</h3>
There are 3 regulatory checkpoints in the life cycle of cells:
- G1: the size of the cell, the presence of growth factors, and the integrity of the DNA are checked before the cell irreversibly commits to division.
- G2: the integrity of the DNA and the correctness of the replication process at the S-phase are checked.
- M: correct attachment of the spindle fibers to the chromosomes at the metaphase plate is checked.
More on cell cycle checkpoints can be found here: brainly.com/question/2128300
Answer:
Iodine
Explanation:
Iodine is needed by animals because the body's metabolic rate is controlled by the action of an iodine hormone, called thyroxine, which is secreted by the thyroid gland in the neck.
If the animal fails to supply enough iodine through food to be able to make a normal amount of this compound, then the thyroid gland enlarges or expands trying to create enough, resulting in a common type of goiter.
Answer: Four amino acids.
Explanation:
RNA (ribonucleic acid) and DNA (deoxyribonucleic acid) are polymers made up of long chains of nucleotides. Thus, a nucleotide is the basic building block of nucleic acids and consists of a sugar molecule (ribose in RNA or deoxyribose in DNA) linked to a phosphate group and a nitrogenous base. <u>The nitrogenous bases can be Adenine (A), Thymine (T), Cytosine (C), Guanine (G) or Uracil (U) replacing T in RNA</u>. DNA is the molecule that stores the genetic information to synthesize polypeptides or proteins (set of amino acids). When proteins need to be created, DNA is transcribed into RNA and this RNA is translated in ribosomes to create polypeptides.
Complementarity is the ability to combine with their complement. A and T (or U) are complementary, while C and G are complementary to each other. Complementarity is the principle of replication and transcription, because it is a propery of both DNA and RNA sequences. Their the nucleotide bases at each position of the sequences are complementary, allowing cells to copy information.
Nucleotides in RNA are grouped into codons, which consist of groups of 3 nucleotides where each codon codes for an amino acid. Therefore, <u>the sequence of bases in nucleic acids determines which protein will be synthesized</u>. Protein synthesis begins with a start codon (AUG, which codes for the amino acid methionine) and ends with a stop codon (UGA, UAG and UAA). So, if there are 15 nucleotides, there are 15 bases. Since they are grouped in groups of 3, we will have a polypeptide of 4 amino acids.
<u>3 nucleotides form a codon, so 12 nucleotides form 4 codons giving 4 amino acids. The last codon, is formed by the last 3 nucleotides and form the stop codon that stop protein synthesis</u>.
I think A is the answer it makes the most sense to me
José probably doesn't feel any pain because his body, during and after exercise released endorphins which are endogenous opioids. This endorphins promote a sense of satisfaction and pleasure, and make pain and discomfort feel irrelevant.
