Lipids part 3 Flashcards
Oxidized derivatives of sterols
Have a sterol nucleus but lack the alkyl chain in cholesterol
More polar
Synthesized from cholesterol
Carried through the body in the bloodstream
Steroid Hormones
Types of Steroid Hormones (2)
Sex hormones
Adrenocortical hormones
Types of Sex Hormones (3)
Androgens (Male)
Estrogens (Female)
Progesterone (prepares the uterus)
Types of adrenocortical hormones (2)
Mineralocorticoids
-Aldosterone controls tissue swelling by regulating the delicate cellular salt balance
Glucocorticoids
-involved in the regulation of glucose metabolism and in the control of inflammations.
Produced by the liver (from cholesterol) stored in the gall bladder and secreted into the intestine.
act like detergents in the small intestine where they keep the
cholesterol in solution and emulsify fats. More accessible to lipases.
Bile Salts
Are present in much smaller amounts than storage or structural lipids
Play vital roles as signaling molecules between nearby cells
Biologically Active Lipids
Plays a regulation of calcium and phosphorous metabolism
Is formed from cholesterol by the action of ultraviolet radiation from the sun
Vitamin D
Vitamin D3 cholecalciferol
lipids found in the oils of some plants and flowers that give them their characteristic odors and colors
composed of two or more sections containing five carbon conjugated structure called isoprene
vitamins A, E, and K are derived from such
Terpenes
required for the formation of the visual pigment found in the retina of the eye
Vitamin A
prevents oxidation of unsaturated fatty acids in cellular membranes (antioxidant).
Vitamin E
needed in the formation of prothrombin for blood clotting.
Vitamin K
arachidonic acid (20:4) derivatives
－Have profound physiological effects at extremely low concentrations.
－Are hormone-like molecules
－Exert their effects in the tissues where they are synthesized.
－Usually have a very short “life.”
Eicosanoids
unsaturated carboxylic acids consisting of a 20–carbon skeleton that contains a cyclopentane ring
– Involved in raising body temperature,
– Inhibiting the secretion of gastric juices,
– Increasing the secretion of a protective mucus layer into the stomach
Prostaglandins (Eicosanoids)
Fatty acid derivative containing three conjugated double bonds and hydroxyl groups
Promote inflammatory and hypersensitivity (allergy) responses.
Leukotrienes (Eicosanoids)
fatty-acid derivative containing a cyclic ether ring and oxygen-containing functional groups
Thromboxanes (Eicosanoids)
Eicosanoid biological processes regulated by prostaglandins, leukotrienes, thromboxanes (6)
Blood Clotting - Thromboxane, Platelets
The inflammatory response - White blood Cells
Reproductive system - PGE2, muscle contraction
Gastrointestinal tract - shown to inhibit the secretion of acid and increase secretion of protective mucus layer
Kidneys - Prostaglandins cause blood vessels to dilate
Respiratory tract - Leukotrienes promote constriction of bronchi
Most common and important complex lipids
-Spherical particles with a lipid core of fatty acids & cholesterol
- Covered with a single membrane layer
- Decorated with proteins that target the particles to specific cell types for uptake & catabolism
Plasma lipoproteins
