Patients suffering from Familial Hypercholesterolemia (FH) can carry a mutation in one of several genes. Two of these genes are ApoB and PCSK9. a. Diagram the normal cholesterol sensing pathway for a healthy person. This should be focused on the molecules that handle cholesterol and that regulate cholesterol production, NOT on patient symptoms. b. On your diagram indicate where a mutation in ApoB disrupts cholesterol sensing. Then write a paragraph or two explaining how cholesterol sensing is specifically disrupted in patients with an ApoB mutation. c. On your diagram indicate where a mutation in PCSK9 disrupts cholesterol sensing. Then write a paragraph or two explaining how cholesterol sensing is specifically disrupted in patients with PCSK9 mutation. -

A hormone signals through a G protein-coupled receptor as shown in the diagram. After the production of IP3, which of these events will MOST quickly stop the transduction of the signal? A. the hydrolysis of IP3 B. the hydrolysis of GTP C. the hydrolysis of PIP2 D. the hydrolysis of the hormone   I believe the answer is (B) the hydrolysisof GTP, because the G protein becomes inactive after GTP is hydrolyzed to GDP.  However, the solution provided by Bartleby is (C).  Please explain.  Thanks

A contributing factor to the development of arthritis is the inappropriate proteolytic destruction of the aggrecan component of cartilage by the proteolytic enzyme aggrecanase. The immune system signal molecule interleukin 2 (IL-2) activates aggrecanase; in fact, IL-2 blockers are sometimes used to treat arthritis. Studies were undertaken to determine whether inhibitors of aggrecanase could counteract the effects of IL-2. Pieces of cartilage were incubated in media with various additions and the amount of aggrecan destruction was measured as a function of time. What is the effect of adding IL-2 to the system? Aggrecan degradation remains the same. Aggrecanase activity is greatly reduced. Aggrecan degradation is greatly reduced. Aggrecan degradation is greatly enhanced. What is the response when an aggrecanase inhibitor is added in addition to IL-2? O Aggrecan degradation remains the same as when IL-2 was added. Aggrecan degradation completely stops. Aggrecan degradation is reduced to…

Imagine a disease that involves reduced expression of receptor X. There is no concentration of full agonist that can restore receptor X signaling back to normal levels. Explain how an allosteric modulator may be used to help in this situation.