-
dehydration reaction is usually defined as
a chemical reaction that involves the loss of a water molecule from the reacting molecule. Dehydration reactions are a subset of elimination reactions. Because the hydroxyl group (–OH) is a poor leaving group, having a Brønsted acid catalyst often helps by protonating the hydroxyl group to give the better leaving group, –OH2+
-
Three fatty acid chains can be added to a molecule of gycerol to form
Triglycerides
-
The fatty acid chains do not need to be of the same size or saturation
any combination is possible
-
-
The formation of triglycerides from three fatty acid chains and a gyceraol molecule is an example of a
dehydration synthesis; Each fatty acid chain ends in a -COOH. The fatty acid's terminal -OH and a -H on gycerol combine to release water (HOH) and the oxygen bridges the glycerol backbone to the fatty acid "tails"
-
Phospholipids are formed when
two fatty tails (carbon and hydrogen only) are joined by a glycerol molecule to a phosphate-containing "head group".
-
Choline is a common
part of head groups
-
Choline, phosphate, gycerol are all group heads that associate with each other and prefer to be around
water
-
Phospholipid tails are made up of only
carbon and hydrogen. Are hydrophobic also.
-
What is an Amphipathic molecule
when it has a polar "head" and a non-polar pair of "tails".
-
Cell membranes are mostly made up of
lipid bilayers
-
Orientation of phospholipid molecules
polar "heads" to inside and outside of cell
non-polar "tails" sandwiched between
-
Explain how phospholipids self-assemble into a lipid bilayer
two separate sheets of polar heads each stay together and associate with water, while their non-polar tails pack in the middle, forming a "sandwich" arrangement.
-
Name at least 5 types of steroids found in the human body
- Testosterone (male sex hormone)
- Cortisol (released in tomes of stress)
- Estradiol (female sex hormone)
- Vitaman D (essential for bone growth and repair)
- Cholesterol (essentail component of the cell membrane)
-
Steroid hormones are based on the
cholesterol molecule
-
Can we live without cholesterol
No, it is an essential component of the cell membrane.
-
Cholesteral has a role in regulating the ________ of cell membranes.
fluidity
-
Is cholesteral soluble by itself in blood
Cholesteral is NOT soluble by itself in blood
in order to reach the cells, it has to be carried by a protein/lipid complex
-
What type of lipids derive from arachidonic acid and are key chemicals in immune defense and inflammation?
- Eicosanoids
- (Prostaglandins and Leukotrienes)
-
Leukotrienes promote
an inflammatory response (for example, swelling) when a sensitive person is exposed to an allergen. By blocking the action of leukotrienes, these inhibitors reduce the inflammatory response.
|
|