Which of the Following Proteins Lacks a PH Domain

question 23

Multiple Choice

Which of the following proteins lacks a PH domain?

• A) Sos (a Ras-GEF)
• B) Grb2 (an RTK signaling adaptor)
• C) Pleckstrin (a protein kinase C substrate)
• D) Akt (protein kinase B)
• E) PDK1 (phosphoinositide-dependent kinase)

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Definitions:

Electron Density

Refers to the probability distribution of electrons in a chemical species; higher density regions indicate a greater likelihood of electron presence.

Internuclear Axis

The imaginary line that runs through the nuclei of two atoms bonded together, defining the direction of the bond.

Sigma Bond

A single covalent bond formed from the direct overlap of atomic orbitals, sharing a pair of electrons between atoms.

Atomic Orbital

A mathematical function that describes the wave-like behavior of either one electron or a pair of electrons in an atom, defining their probability distribution around a nucleus.