<span><span>anonymous </span> 3 years ago</span>Proteins are involved in almost all of the cell's functions. They can act as:
Transportation: they can transport hydrophobic molecules in blood for example
Regulation: protein hormones and enzymes
Receptor: can act as receptors on cell surface and in the subsequent signal transduction (G-protein for instance)
It is true that all proteins are made up of up to 20 amino acids, but there are several reasons for their diverse actions:
-One reason is the possible sequence and number of amino acids: Met-Ser-His is different from Met-His-Ser for example. Besides, you have different chain length, for a protein is made up of long chain of polypeptide (longer than 50-70 amino acids) and can have any of the 20 amino acids with repetition, so using simple probability, this can provide up to practically unlimited combination with proteins that have chains of thousands of amino acids.
-Another very crucial reason for the diversity of protein action is the conformation. A protein passes by at least 3 conformational stages before becoming mature. The straight amino acid chain is the primary structure of the protein that can never be active. Spatial modification of this primary structure results in a secondary structure, Helix or Beta-pleated sheets (or other coiling structure), that is also inactive. Further coiling and bending of the secondary structure produce a 3-dimentional conformation that is the active form of the protein. Moreover, many proteins can undergo further conformational rearrangement and combination with other protein sub-units producing a quaternary structure.
The pattern of inheritance results from individual organisms having many different genes working at the same time to control a single trait is called Polygenic Traits or / inheritance that are may be located near each other or even on separate chromosomes.
A benign tumour is generally not dangerous as they grow usually within a membrane in one space. They can however grow really big in a short space of time and can cause pressure on neighbouring blood vessels which can be dangerous.
Metastatic or malignant tumours are dangerous and cancerous. After they grow, some cells break off and travel in the bloodstream to a different area of the body (usually the main organs) and forms a secondary tumour there. This keeps happening until the cancer has spread to all of the body.
**_hope this helps**
Answer:
<u>The correct answer is that our student accumulated lactic acid.</u>
Explanation:
<u>What is acid lactic and where it comes from?</u> It comes from the breakdown of glucose when there is no oxygen present (glycolytic metabolism), that is, in an anaerobic exercise such as running or cycling at high speed, like the case of our student, where there is a high intensity and a very short duration.
<u>What happen then? </u>When we keep doing exercise with high intensity an exercise, lactic acid will begin to accumulate by not giving the body time to remove it.
<u>How can we avoid lactic acid?</u> With training, there is no more. Based on training, the body deploys adaptive mechanism that causes lactic acid not to accumulate so quickly and if it begins to do so, the muscle supports it more effectively.
Answer:
Ligand-receptor interaction is the first interaction that triggers cell signalling.
Ligands are the hormones, drugs or neurotransmitters that specifically bind with receptors present in cell surface to initiate cell signalling. Ligand binding to the receptor is reversible. Binding of the ligand to the receptor can activate or inactivate receptor. Activation may lead to cell signalling pathways. Inside cells, there are secondary molecules which on activation starts a cascade of reactions. which in-turn regulate the function of the ligand molecule.
At first, the activated receptor relates with G proteins molecules in the cell.
before the ultimate physiological effect of the ligand on the cell's behavior is produced Therefore, the cellular signaling starts as soon as the first messenger (the ligand) binds to its receptor.
hope this helps
