What is mysterious about the K+ channel that requires an explanation?
A. It is both ligand gated and voltage gated
B. It works against a potassium gradient
C. It excludes sodium, which is a smaller ion
D. Sugar is unable to pass through the channel
Answer: C
Biochemistry
- Certain enzymes, like those in the Glycogen Breakdown Cascade, are active only when phosphorylated. Suppose you wanted to produce a version of the enzyme that is constitutively active, i.e. active all the time? You can alter the gene and replace a certain:
- Protein Kinase A binds to the sequences RRGSE in substrate proteins, and transfers a phosphate from ATP to the Serine (S) in that sequence. A protein with the sequence RRGAE would be called what?
- Cholesterol is most abundant in animal cell membranes (from amoebas to vertebrates) where it
- Glycolipids are membrane lipids which contain:
- When insulin signals ingestion of food, GLUT-4 receptors are:
- Calcium is kept low in the cytoplasm, but "spikes" of Ca+2 concentration function as effective signals. What protein detects the presence of Calcium ion?
- One of the second messengers in Protein Kinase C activation is quite polar. It is often known by its abbreviation:
- The voltage gated sodium channel in never cells has about how many transmembrane helices?
- The Acetylcholine Receptor is:
- Cholesterol is found in membranes of which?
- The Acetylcholine receptor is
- If a transmemberane protein admits a sodium ion along with a molecule of Glucose (assuming that the sodium levels inside the cell is low) then this is an example of:
- Several cofactors including Coenzyme A, FAD, and NAD have what in common?
- When [ATP] = 5mM, [ADP] = 4mM, and [AMP] = 1mM, the Atkinson Energy Charge Function has the value:
- When it is active, Protein Kinase C is:
- Which Phospholipase removes the polar head group along with the attached P?
- An uncompetitive inhibitor causes what apparent changes?
- If a given substrate has a high Km with an enzyme we usually assume
- What are the dimensions (units) of the turnover number - k2 or kcat?
- Which is correct?
- What is fluid in the fluid mosaic model?
- Which of these is a reducing sugar?
- Which of the following is NOT mediated by a 7TM protein?
- What is the value of the Atkinson's Energy Charge Function when [AMP] = 1 M, [ADP] = 2M, and [ATP] = 5M?