MCAT Practice Test 1

10 free MCAT practice questions in the real exam format, covering the official content areas, with an explanation for every answer.

MCAT Practice Test 1Tutor mode

Question 1 of 10

Biological and Biochemical Foundations of Living Systems

What is the approximate net charge of the tetrapeptide His-Glu-Lys-Ala at pH 7.4? (Approximate $p K_{a}$ values: α-amino group 9.0, α-carboxyl group 2.3, side chains of His 6.0, Glu 4.1, and Lys 10.5.)