CONNECTIVE TISSUE GLAND
ENDOCRINE
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
made from chains of amino acids
|
|
made from cholesterol
|
|
soluble in water
|
|
non-soluble in water
|
Detailed explanation-1: -Like cholesterol, steroid hormones are not soluble in water (they are hydrophobic). Because blood is water-based, lipid-derived hormones must travel to their target cell bound to a transport protein.
Detailed explanation-2: -Structure of Steroid Molecules Unlike phospholipids and fats, steroids have a fused ring structure. Although they do not resemble the other lipids, they are grouped with them because they are also hydrophobic and insoluble in water.
Detailed explanation-3: -Because all steroid hormones are derived from cholesterol, they are not soluble in plasma and other body fluids.
Detailed explanation-4: -Steroid hormones estrogen and testosterone are non-polar and can pass through the lipid bilayer without binding to a membrane receptor. Nonpolar steroid hormones bind to special receptors in the cell cytoplasm. These receptors are modified and migrate to the cell nucleus where they activate transcription.