Biology MCAT Practice Questions
609 free Biology MCAT-style practice questions, covering topics like The Cell, Reproduction, Embryogenesis, The Nervous System, The Endocrine System, The Respiratory System, and more.
Which of the following prokaryotic structures is involved in conjugation, a form of horizontal gene transfer?Which chamber of the heart pumps oxygenated blood to the rest of the body?Which of the following structures stores calcium ions necessary for muscle contraction?The hormone released by the adrenal glands in response to stress is:Which of the following structures allows some prokaryotic cells to move in their environment?Which neurotransmitter is primarily responsible for the inhibition of neuronal activity in the central nervous system?Which of the following is an example of a physical barrier in the innate immune system?Which of the following layers of the skin is most involved in insulation and energy storage?Which component of blood accounts for the largest proportion by volume?Which of the following is a characteristic of polycystic ovary syndrome (PCOS)?Which of the following statements about arteries and veins is correct?Which of the following is an example of a genetic mutation?Which of the following scenarios is most likely to result in a frameshift mutation?Which of the following is characteristic of microglia?Which of the following is the primary nitrogenous waste product excreted in urine?In a genetic cross involving two genes, AaBb x AaBb, what is the probability of obtaining an offspring that is…Which component of the cell theory states that cells arise from pre-existing cells?During which phase of the adaptive immune response do memory B cells primarily function?Which type of neurotransmitter receptor directly causes ion channels to open upon binding?Which process involves the elimination of indigestible materials from the body?Which of the following neurotransmitters is associated with the reward system in the brain?In which respiratory disorder does the body's immune system mistakenly attack the alveoli, leading to inflammation and scarring?Which of the following types of mutations is most likely to have the greatest impact on protein structure and function?Which muscular movement propels food through the esophagus and into the stomach?During which phase of mitosis do the chromosomes line up along the equatorial plane of the cell?In RNA interference (RNAi), what is the function of the RNA-induced silencing complex (RISC)?Which of the following structures prevents the collapse of the trachea?Which type of joint allows for the widest range of motion?Which of the following structures is characteristic of prokaryotic cells but absent in eukaryotic cells?Which of the following organelles is involved in the breakdown of cellular waste and foreign material in eukaryotic cells?Which of the following is NOT a factor that affects the rate of gas diffusion across the respiratory membrane?Where does fertilization of the egg by sperm typically occur in humans?Which of the following is an example of a genetic inheritance pattern?The process of expiration is primarily a result of:Which hormone is responsible for inducing milk production in the mammary glands after childbirth?During spermatogenesis, which cell type directly gives rise to sperm cells?Which of the following is NOT a function of the respiratory system?Which of the following is the primary function of the skeletal system?Which of the following hormones is responsible for stimulating milk ejection from the mammary glands during breastfeeding?Which of the following organelles is involved in protein synthesis in eukaryotic cells?During which phase of the cell cycle does the centrosome duplicate, forming two centrosomes?A population of rabbits lives in an area with patches of dense vegetation separated by open fields. Over time, the…Which of the following endocrine glands is responsible for secreting the hormone melatonin, which regulates sleep-wake cycles?Which of the following cell types is responsible for antigen presentation to T-cells in the lymph nodes?Which of the following hormones is NOT involved in regulating digestive processes related to absorption and defecation?Crossing over occurs during which phase of meiosis?In fetal circulation, what is the main function of the placenta?Which of the following mechanisms describes negative feedback regulation of hormone secretion?During embryonic development, the process by which cells become specialized and take on specific functions is known as:Which structure increases the surface area of the small intestine, enhancing nutrient absorption?