A steroid-derived hormone that must be activated by hydroxylation, ______ regulates Ca2+ metabolism.
a. sterol
b. cholesterol
c. arachidonic acid
d. vitamin D
Answer: vitamin D
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Animal Biology
- The Ig fold can be described as a
- Which statement about antigen-binding sites in antibodies is false?
- Fab fragments can be generated by
- How many antigen-binding sites are present on an IgM molecule?
- How many antigen-binding sites are present on an IgG molecule?
- Which class of antibodies has been implicated in allergic reactions?
- IgG is one of five classes of antibodies that can be produced by our immune system. IgGs have a molecular mass of approximately 150 kDa, what is their subunit composition?
- IgG is the most common immunoglobulin in the circulatory system and in the extravascular fluid. It is composed of two light chains and two heavy chains. What is the approximate molecular mass of an IgG molecule?
- How many different classes of antibodies are produced by the human immune system?
- Humoral immunity is mediated by soluble molecules. Which cell type produces the soluble molecules that carry out the humoral immunity?
- Treadmilling refers to
- Humoral immunity refers to that part of the immune response that is mediated by
- Which of the following statements about actin is not true?
- Which statement about actin is correct?
- Muscle contraction is triggered
- During muscle contraction myosin heads
- The energy needed to drive muscle contraction comes from ATP hydrolysis that is carried out by
- Which statement about actin is not true?
- Which statement about myosin is not true?
- During muscle contraction
- What are the main bonds or forces that stabilize the dimer formed by two myosin heavy chains?
- Which of the statements about muscle contraction is not true?
- Which of the statements about muscle contraction is correct?
- Muscle contraction is directly caused by
- Muscle contraction is directly caused by