<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.
Explanation:
During endocytosis large cells, particles, and cell fragments moved across the plasma membrane through a process of invagination; part of the external cell membrane folds into itself and creates a small pocket that surrounds the target molecule, this breaks off from the membrane to form an intracellular vesicle.
Specific endocytosis processes, such as phagocytosis, pinocytosis, and endocytosis are regulated by receptors-they take in cells, fluids, and specific compounds respectively. During phagocytosis, cells absorb large particles in cell compartments called phagosomes, after which specifically enzyme-containing lysosomes break them down.
Learn more about membrane components at brainly.com/question/1971706
Learn more about plasma membrane transport at brainly.com/question/11410881
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Answer:
Neil Shubin bases his argument that the anatomy of Tiktaalik is relevant to that of humans by discussing specific features of the anatomy of Tiktaalik that vary from typical fish anatomy and correspond to features of the human body. For example, he points out that Tiktaalik has a neck that is able to bend independently of the rest of the body, unlike fish, and like all terrestrial vertebrates, including humans. Therefore, the evolutionary history of humans can be traced to an organism similar to Tiktaalik, resulting in the concept of the "inner fish."
Explanation:
Answer:
200.000 in je m
Explanation:
1 je m is equal to 1000 mm.
Therefore 0.2 mmm will be equal to 1000 × 0.2 mmm
This will give us 200 je m.
The child could be night blind or have normal vision.<span>
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