cholesterin
Học thuậtThân thiện
Definition
Noun: 1. A crystalline sterol alcohol: A white, waxy, crystalline substance (C₂₇H₄₅OH) that is a sterol alcohol. It is synthesized in the liver and is a normal constituent of bile. 2. A key animal sterol: An animal sterol that is a fundamental structural component of animal cell membranes and a precursor for the synthesis of steroid hormones, vitamin D, and bile acids.
Usage and Examples
- As a normal physiological component:
- Cholesterin is essential for building and maintaining cell membranes.
- The liver produces cholesterin to aid in digestion.
- In a medical or biochemical context:
- High levels of cholesterin in the blood can be a risk factor for heart disease.
- The study measured the cholesterin content in various tissues.
Advanced Usage
- "Free cholesterin": Refers to cholesterol that is unesterified, meaning it is not bound to a fatty acid. This form is a component of cell membranes.
- "Serum cholesterin": A term used in clinical contexts to refer to the concentration of cholesterol in the blood serum.
Variants and Related Words
- Cholesterol (n): This is the far more common and modern term for . The two words are synonymous, with "cholesterol" being the preferred term in contemporary English, especially in medical and general usage.
- Doctors often check patients' cholesterol levels.
Different Meanings
- The word has only one core meaning, which is chemically and biologically identical to cholesterol. The variation is purely lexical (a difference in the word form itself).
Synonyms
- Cholesterol: The direct and primary synonym.
- Sterol: A broader category of organic compounds to which cholesterin belongs. (Note: Not all sterols are cholesterin).
Notes on Usage
- Historical/Technical Term: is an older term. In modern English, cholesterol is universally used. You will encounter primarily in older scientific literature or in specific technical/commercial compound names.
- Word Origin: The word comes from the Greek (bile) and (solid), with the suffix common in chemistry for certain substances, reflecting its discovery in gallstones.
Noun
- an animal sterol that is normally synthesized by the liver; the most abundant steroid in animal tissues