MCAT COMPLETE EXAM PREP 2026 2027 Featuring Practice Tests, Verified Answers, Biology, Chemistry & CARS Review Guide

MCAT COMPLETE EXAM PREP 2026–
2027 Featuring Practice Tests, Verified
Answers, Biology, Chemistry & CARS
Review Guide

1. Which of the following is the primary function of the mitochondria?
A. Protein synthesis
B. Lipid synthesis
C. ATP production
D. DNA replication
C. ATP production
2. The process of glycolysis occurs in which cellular location?
A. Mitochondrial matrix
B. Cytoplasm
C. Nucleus
D. Endoplasmic reticulum
B. Cytoplasm
3. Which of the following enzymes is responsible for the conversion of
pyruvate to acetyl-CoA?
A. Pyruvate kinase
B. Pyruvate carboxylase
C. Pyruvate dehydrogenase
D. Lactate dehydrogenase
C. Pyruvate dehydrogenase
4. A mutation in the gene encoding the hemoglobin beta chain results in sickle
cell disease. This is an example of which type of mutation?
A. Frameshift mutation
B. Nonsense mutation
C. Missense mutation
D. Silent mutation
C. Missense mutation

,5. Which of the following is NOT a component of the eukaryotic cell
membrane?
A. Phospholipids
B. Cholesterol
C. Peptidoglycan
D. Proteins
C. Peptidoglycan
6. The electron transport chain is located in which part of the mitochondria?
A. Outer membrane
B. Intermembrane space
C. Inner membrane
D. Matrix
C. Inner membrane
7. During DNA replication, which enzyme synthesizes the new DNA strand?
A. Helicase
B. DNA polymerase
C. RNA polymerase
D. Ligase
B. DNA polymerase
8. Which of the following is a characteristic of an enzyme-catalyzed reaction?
A. It alters the equilibrium constant
B. It increases the activation energy
C. It decreases the activation energy
D. It changes the free energy of the reaction
C. It decreases the activation energy
9. The process of transcription produces which of the following molecules?
A. DNA
B. mRNA
C. Protein
D. Fatty acid
B. mRNA
10.Which organelle is responsible for the modification and packaging of
proteins for secretion?
A. Rough endoplasmic reticulum
B. Smooth endoplasmic reticulum

, C. Golgi apparatus
D. Lysosome
C. Golgi apparatus
11.The citric acid cycle occurs in which compartment of the mitochondria?
A. Outer membrane
B. Intermembrane space
C. Inner membrane
D. Matrix
D. Matrix
12.Which of the following is a purine base?
A. Cytosine
B. Thymine
C. Uracil
D. Adenine
D. Adenine
13.The sodium-potassium pump is an example of which type of transport?
A. Simple diffusion
B. Facilitated diffusion
C. Active transport
D. Osmosis
C. Active transport
14.Which of the following is responsible for the termination of translation?
A. Start codon
B. Stop codon
C. Ribosome
D. tRNA
B. Stop codon
15.The structure of DNA is described as a:
A. Single helix
B. Double helix
C. Triple helix
D. Branched chain
B. Double helix

, 16.Which of the following hormones is produced by the pancreas?
A. Insulin
B. Thyroid hormone
C. Cortisol
D. Epinephrine
A. Insulin
17.The primary structure of a protein refers to:
A. The sequence of amino acids
B. The folding of the polypeptide chain
C. The arrangement of multiple subunits
D. The three-dimensional shape
A. The sequence of amino acids
18.Which of the following is a function of the smooth endoplasmic reticulum?
A. Protein synthesis
B. Lipid synthesis
C. ATP production
D. DNA replication
B. Lipid synthesis
19.The process of meiosis results in the production of:
A. Two diploid cells
B. Two haploid cells
C. Four diploid cells
D. Four haploid cells
D. Four haploid cells
20.Which of the following is a cofactor for the enzyme catalase?
A. Zinc
B. Iron
C. Magnesium
D. Calcium
B. Iron
21.The lac operon in bacteria is an example of:
A. Positive regulation
B. Negative regulation
C. Both positive and negative regulation