Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
20 Cards in this Set
- Front
- Back
|
5 Classes of Lipids |
1. Free fatty acids (FA) --> simplest type of lipid 2. Triacylglycerols --> storage form of FA (fatty acids) 3. Phospholipids 4. Glycoproteins 5. Steroids --> most common form is cholesterol |
|
|
Triacylglycerols (storage form of FA) are formed by the attachment of 3 FA chains to a glycerol molecule, which are attached through __________________________. |
Ester linkages |
|
|
True or False: FAs store energy more efficiently than carbohydrates in the form of triacylglycerol due to the exclusion of H20 (anhydrous) |
True |
|
|
What is the structure of Phospholipids (major class of membrane lipids)? |
Phospholipids are built on a sphingosine backbone called sphingolipids, which are amino acids that contain a long, unsaturated hydrocarbon |
|
|
Steroids are lipids that function as powerful hormones. Which is the most common? |
Cholesterol |
|
|
Steroids exhibit a ______(a)______ structure, which is called the __________(b)__________. |
a. cyclical b. steroid nucleus |
|
|
True or False: Ketones are a fuel source that are water insoluble. |
FALSE (Ketones are water soluble) |
|
|
Within the 3 stage process of FA synthesis, what is the committed step? |
Activation of acetyl CoA to malonyl CoA (this is stage 2, following the preparatory step, which is the start to FA synthesis) |
|
|
Step 1 of FA synthesis is the preparatory step, where _______(a)______ is transferred from the ______(b)______ to the ______(c)______ (FA synthesis site). |
a. acetyl CoA b. mitochondria c. cytoplasm |
|
|
Describe the 3rd and final step of FA synthesis. |
Reaction intermediates are attached to an acyl carrier protein |
|
|
What is the end product of fatty acid synthesis? |
Palmitate (Palmitate in animal cells is the precursor of other long-chained FAs) |
|
|
_______ is the major carrier of cholesterol in the blood. |
LDL (Low Density Lipoprotein) |
|
|
What are the 2 factors that determine the movement of molecules across a membrane? |
1) molecule solubility and 2) concentration gradient |
|
|
______________ induced by ligand binding is another mechanism of initiating signal transduction |
Dimerization (Ligand binding to receptor monomers causes them to dimerize by interactions between the extracellular domains. Dimerization is made possible by the ability of membrane proteins to move laterally within the membrane bilayer) |
|
|
Insulin signaling regulates metabolism, and the binding of insulin initiates __________________. |
Autophosphorylation [this creates docking sites for insulin-receptor substrates (IRS), which then eventually propagates the signal to Protein Kinase B (Akt)] |
|
|
True or False: Protein Kinase B (PKB, Akt) plays a critical role in glucose metabolism. |
TRUE (Akt initiates signaling that brings GLUT4 transporter to the cell membrane, allowing glucose to enter the cell) |
|
|
Explain how Calcium is a cytoplasmic messenger. |
Calmodulin serves as a calcium sensor in all eukaryotic cells, which is activated by the binding of calcium. |
|
|
Na + K ATPase Pump controls cell volume, ____________________, and drives transport. |
Membrane potential (Voltage-gated channels open in response to membrane potential changes) |
|
|
True or False: Membrane fluidity is controlled by FA and cholesterol content, and temperature regulates the transition from rigid to fluid. |
TRUE (cholesterol acts as a buffer, increasing fluidity at low temperatures and decreasing fluidity at high temperatures. The content of unsaturated fatty acids in our phospholipids also affects membrane fluidity, as the increase in the amount of unsaturated fatty acids in our cell membrane causes the increase in fluidity) |
|
|
What are the 3 main ways the regulation of cholesterol synthesis is controlled? |
1. Rate of synthesis 2. Rate of translation 3. Degredation |
