Kaplan Ch.5 - Lipids Flashcards
What is the function of a phosphoglyceride?
Form membranes, The polar head group is responsible for surface properties and play a role in signaling, recognition and binding
What is the function of sphingolipids?
Recognition at cell surface
What are the 4 major subdivisions of sphingolipids?
1) ceramide
2) sphingomyelin
3) cerebroside/globoside
4) ganglioside
What is an important function of sphingomyelins?
Major component of cell membranes in Schwann cells and oligodendrocytes that produce myelin on axons
What is a cerebroside / globoside?
Where are they located?
Both are sphingolipids that are attached to sugar via glycosidic linkage.
Cerebroside = attached to 1 sugar Globoside = attached to multiple sugars
Located on outer surface of cell membrane
What is a ganglioside?
What is it’s function?
Ganglioside = sphingolipid connected to oligosaccharide (short chain of sugar molecules) which is then bonded to sialic acid, carries a negative charge.
Major role in cell:cell interaction, recognition and signal transduction
What are waxes?
What is their function?
Waxes are long chain fatty acids with long chain alcohols.
In plans function is protection against dehydration and predators.
In animals function is to protect against dehydration.
What is a terpene?
Chemicals with distinct smells in animals and plants. Also precursors to steroids.
What is cholesterol?
What is it’s importance?
Cholesterol = steroid, major component of phospholipid bilayer
Function = maintain membrane fluidity, at low temp it keeps membrane from becoming too rigid, at high temp keeps membrane from breaking apart or becoming too permeable. Precursor for other molecules
Prostaglandins:
1) Where are they produced?
2) what is their basic structure?
3) what is their function?
1) all cells
2) unsaturated 20 carbon carboxylic acids
3) regulate synthesis of cAMP
What is a vitamin?
Essential nutrient that cannot be synthesized by body and must be consumed by diet
Vitamin A (carotene)
1) structure
2) retinal
3) retinol
1) unsaturated hydrocarbon that is important in vision, growth/development and immune system
2) aldehyde metabolite of vitamin A, component of light sensing systems in eye
3) alcohol storage form of vitamin A, can be oxidized to form retinoic acid, important hormone that regulates gene expression of epithelium
Vitamin D:
1) how is this vitamin obtained?
2) what important compound is this conveyed to?
3) what can deficiency in vitamin D during development lead to?
1) In diet or by UV light reaction in skin
2) calcitriol, which increases calcium and phosphate uptake in intestines promoting bone production
3) rickets = underdeveloped curbed king bones and impeded growth
Vitamin E:
1) what is important to know about the structure of this vitamin?
2) what is the function of vitamin E?
1) it contains a substituted aromatic ring
2) acts as antioxidant destroying free radicals
Vitamin K:
1) what is important about the structure of vitamin K?
2) what functions does this vitamin perform?
1) aromatic ring
2) posttranslational modification of prothrombin (precursor for thrombin = blood clotting factor), also requires to introduce calcium binding sites on calcium dependent proteins
