Lecture 3 - Exam 1 Flashcards
(28 cards)
The glucose molecule can exist in an…?
Open-chain (acyclic) as well as ring (cyclic) form.
What form is the predominate form of glucose in cells?
Cyclic form
The ring-closing reaction can give _____ products, what are they?
Two
The two products are denoted alpha and beta depending on the configuration.
Monosaccharides form cyclic structures when?
Monosaccharides contain five or more carbon atoms, they form cyclic structures.
Monosaccharides are joined together by __________ (_____) resulting in _____.
Dehydration reaction (H2O is removed) ; glycosidic bonds
Note: The glycosidic linkage contains an ether linkage.
What are oligosaccharides?
Polymers of a few sugars.
What are polysaccharides?
Macromolecules ; polymers of hundreds or thousands of sugars.
What is glycogen and starch?
Are the storage forms of carbohydrates in animals and plants, respectively.
To store glucose (AKA energy!!)
Amylopectin (starch) : ______ bonds join two chains at a branch point.
alpha-1,6
Glycogen: Most residues are joined by _________ bonds.
alpha-1,4
Cellulose: Residues are joined by _______ bonds.
beta-1,4
In addition of being the major source of energy, oligosaccharides and polysaccharides also play roles in…?
Protein folding and act as markers involved in cell recognition and interactions.
What is a glycoprotein?
Protein with carbohydrate attached.
What is a glycolipid?
Lipid with carbohydrate attached.
What are the three major roles of lipids?
Energy storage, major component of cell membranes, and important in cell signaling as steroid hormones and messenger molecules.
What are lipids primarily made of?
What are their characterisitics?
Lipids are molecules primarily made of hydrocarbons.
They are insoluble in water (create balls in the water, hiding from the forces of water) and greasy to the touch.
What are the simplest lipids?
Fatty acids.
What are fatty acids?
Long hydrocarbon chains (16 or 18 carbons) with a carboxyl group (COO-) at one end.
What are unsaturated fatty acids?
Have one or more double bonds.
What are saturated fatty acids?
No double bonds.
The hydrocarbon chain in fatty acids are hydrophilic or hydrophobic?
Hydrophobic
Which type of fatty acid is supposed to be healthier?
Unsaturated because they’re kinky and don’t like to stick together.
What are fatty acids stored as?
Stored as fats.
More specifically, triacylglycerols (triglycerides, or fats) : three fatty acids linked to a glycerol molecule.
Fatty acids can be broken down for use in…?
Energy-yielding reactions.
They yield >2X the amount of energy as carbs!!! important for animal mobility.
