medium · MCAT bio-biochem
Acute stress triggers the 'fight-or-flight' response via the adrenal medulla, while chronic stress involves the adrenal cortex.
How do the signaling mechanisms of epinephrine and cortisol differ in terms of their molecular interaction with target cells?
- Cortisol binds to a receptor tyrosine kinase (RTK) on the cell surface; Epinephrine instead relies on a voltage-gated ion channel.
- Epinephrine enters the nucleus to directly induce new protein synthesis; Cortisol instead activates an enzymatic cascade in the cytoplasm.
- Epinephrine binds to cell-surface G-protein coupled receptors; Cortisol binds to intracellular receptors that act as transcription factors.
- Both hormones bind to ligand-gated ion channels embedded within the plasma membrane, together inducing rapid depolarization of the target cell.
Sign up free to see the explanation and track your rank →
More MCAT bio-biochem practice
- In the human ear, sound waves cause fluid in the cochlea to… — Which cells are responsible
- An electrophysiologist observes a neuron at its resting memb… — Which ion is primarily res
- Which organelle would you expect to be exceptionally well-developed in these cells?
- What genetic term describes a single gene influencing multiple seemingly unrelated traits?
- Which structure is most likely dysfunctional?
- A researcher discovers that a population of bacteria survives exposure to an antibiotic be
- A patient is admitted to the emergency department with a sev… — How does this patient's O_
- Which molecule acts as a 'fluidity buffer' in animal cell membranes?