CONNECTIVE TISSUE GLAND
ENDOCRINE
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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steroid
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amino acid
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fatty acid
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carbohydrate
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Detailed explanation-1: -Amino acid derived hormones and polypeptide hormones are not lipid-derived (lipid-soluble) and therefore cannot diffuse through the plasma membrane of cells. Lipid insoluble hormones bind to receptors on the outer surface of the plasma membrane, via plasma membrane hormone receptors.
Detailed explanation-2: -Water-soluble hormones cannot diffuse through the cell membrane. These hormones must bind to a surface cell-membrane receptor. The receptor then initiates a cell-signaling pathway within the cell involving G proteins, adenylyl cyclase, the secondary messenger cyclic AMP (cAMP), and protein kinases.
Detailed explanation-3: -Amino acid-derived hormones and polypeptide hormones are not lipid-derived (lipid-soluble or fat-soluble); therefore, they cannot diffuse through the plasma membrane of cells.
Detailed explanation-4: -Peptide hormones such as oxytocin and growth hormone consist of polypeptide chains of amino acids. Because these hormones are water-soluble and insoluble in lipids, they cannot pass through the plasma membrane of cells; their receptors are found on the surface of the target cells.
Detailed explanation-5: -Amino acid derivatives, such as epinephrine, are water-soluble molecules derived from amino acids (the building blocks of protein). These hormones are stored in endocrine cells until needed. They act by binding to protein receptors on the outside surface of the cell.