MCAT / MDCAT Practice Test
Instructions:
- Select the correct option for each question.
- The answers to the following MCQs can be viewed by clicking here. The answer key will open in a separate window.
A. Biology Section
- The basic structural and functional unit of life is:
A. Tissue
B. Organ
C. Cell
D. Organelle
- Which organelle is known as the powerhouse of the cell?
A. Ribosome
B. Nucleus
C. Mitochondrion
D. Golgi apparatus
- Which biomolecule stores genetic information?
A. Lipids
B. Carbohydrates
C. Proteins
D. Nucleic acids
- The process of diffusion does not require:
A. Concentration gradient
B. Energy
C. Movement of particles
D. Semi-permeable membrane
- Which phase of mitosis involves alignment of chromosomes at the equator?
A. Prophase
B. Metaphase
C. Anaphase
D. Telophase
- Which kingdom includes organisms lacking a true nucleus?
A. Protista
B. Fungi
C. Plantae
D. Monera
- DNA replication occurs during:
A. G1 phase
B. S phase
C. G2 phase
D. M phase
- Which scientist proposed the theory of natural selection?
A. Mendel
B. Darwin
C. Lamarck
D. Watson
- The movement of water across a selectively permeable membrane is called:
A. Diffusion
B. Active transport
C. Osmosis
D. Endocytosis
- Which blood cells are responsible for immunity?
A. RBCs
B. Platelets
C. WBCs
D. Plasma cells
- The site of photosynthesis in plant cells is:
A. Vacuole
B. Chloroplast
C. Ribosome
D. Nucleus
- The human heart has:
A. Two chambers
B. Three chambers
C. Four chambers
D. Five chambers
- Which enzyme digests proteins in the stomach?
A. Amylase
B. Lipase
C. Pepsin
D. Trypsin
- The functional unit of kidney is:
A. Neuron
B. Alveolus
C. Nephron
D. Osteon
- Which gas is released during photosynthesis?
A. Carbon dioxide
B. Nitrogen
C. Oxygen
D. Hydrogen
- The pH of human blood is approximately:
A. 5.5
B. 6.0
C. 7.4
D. 8.5
- Which hormone regulates blood sugar level?
A. Thyroxine
B. Insulin
C. Adrenaline
D. Estrogen
- Which part of the brain controls balance?
A. Cerebrum
B. Medulla
C. Cerebellum
D. Hypothalamus
- The genetic makeup of an organism is called:
A. Phenotype
B. Genotype
C. Allele
D. Trait
- The universal donor blood group is:
A. A
B. B
C. AB
D. O
- Which tissue transports water in plants?
A. Phloem
B. Cortex
C. Xylem
D. Epidermis
- ATP is mainly synthesized in:
A. Ribosomes
B. Lysosomes
C. Mitochondria
D. Vacuoles
- The opening and closing of stomata is controlled by:
A. Companion cells
B. Guard cells
C. Xylem cells
D. Root hairs
- Which vitamin is synthesized in the skin by sunlight?
A. Vitamin A
B. Vitamin B
C. Vitamin C
D. Vitamin D
- Which blood vessel carries oxygenated blood from lungs to heart?
A. Pulmonary artery
B. Aorta
C. Pulmonary vein
D. Vena cava
- The process of formation of gametes is called:
A. Fertilization
B. Mitosis
C. Meiosis
D. Budding
- Which structure is absent in animal cells?
A. Cell membrane
B. Mitochondria
C. Cell wall
D. Ribosomes
- Which scientist is known as the father of genetics?
A. Darwin
B. Mendel
C. Pasteur
D. Hooke
- Which process produces identical daughter cells?
A. Meiosis
B. Fertilization
C. Mitosis
D. Crossing over
- RNA differs from DNA because RNA contains:
A. Thymine
B. Deoxyribose sugar
C. Uracil
D. Double helix
- Which organ removes urea from blood?
A. Liver
B. Kidney
C. Spleen
D. Pancreas
- The largest artery in the human body is:
A. Pulmonary artery
B. Coronary artery
C. Aorta
D. Renal artery - The process by which green plants make food is:
A. Respiration
B. Digestion
C. Photosynthesis
D. Fermentation
- Which component of blood helps in clotting?
A. RBCs
B. Plasma
C. Platelets
D. Lymphocytes
- The site of aerobic respiration is:
A. Cytoplasm
B. Nucleus
C. Mitochondria
D. Ribosome
- Which hormone is secreted by thyroid gland?
A. Insulin
B. Thyroxine
C. Testosterone
D. Cortisol
- The exchange of gases in lungs occurs in:
A. Bronchi
B. Trachea
C. Alveoli
D. Larynx
- The study of insects is called:
A. Entomology
B. Herpetology
C. Ornithology
D. Ecology
- Which blood group is universal recipient?
A. O
B. AB
C. A
D. B
- Which process increases genetic variation?
A. Binary fission
B. Budding
C. Meiosis
D. Mitosis
- Which nitrogenous base pairs with adenine in DNA?
A. Guanine
B. Cytosine
C. Uracil
D. Thymine
- The normal human chromosome number is:
A. 23
B. 44
C. 46
D. 48
- Which part of neuron receives impulses?
A. Axon
B. Dendrite
C. Myelin sheath
D. Synapse
- Which organelle packages proteins?
A. Ribosome
B. Golgi apparatus
C. Lysosome
D. Nucleolus
- Which disease is caused by deficiency of insulin?
A. Goiter
B. Diabetes mellitus
C. Rickets
D. Scurvy
- The movement of molecules from low to high concentration is:
A. Osmosis
B. Diffusion
C. Active transport
D. Filtration
- Which part of flower develops into fruit?
A. Ovule
B. Ovary
C. Stigma
D. Anther
- Which scientist discovered penicillin?
A. Fleming
B. Jenner
C. Pasteur
D. Darwin
- The outer protective covering of plant cells is:
A. Plasma membrane
B. Cell wall
C. Cytoplasm
D. Capsule
- The process of breaking down glucose to release energy is:
A. Photosynthesis
B. Respiration
C. Digestion
D. Assimilation - Which structure carries hereditary information?
A. Ribosome
B. Chromosome
C. Centriole
D. Vacuole - The primary source of energy for ecosystems is:
A. Wind
B. Water
C. Sun
D. Soil - The process of losing water through leaves is:
A. Respiration
B. Guttation
C. Transpiration
D. Diffusion - Which part of the digestive system absorbs most nutrients?
A. Stomach
B. Large intestine
C. Small intestine
D. Esophagus - Which blood vessel carries deoxygenated blood to lungs?
A. Aorta
B. Pulmonary artery
C. Pulmonary vein
D. Coronary artery - The fluid mosaic model describes the structure of:
A. Cell wall
B. Cytoplasm
C. Plasma membrane
D. Nucleus - Which organelle contains hydrolytic enzymes?
A. Ribosome
B. Lysosome
C. Vacuole
D. Centriole - The inability to see in dim light is due to deficiency of:
A. Vitamin A
B. Vitamin B
C. Vitamin C
D. Vitamin K - Which process occurs in ribosomes?
A. DNA replication
B. Protein synthesis
C. Lipid digestion
D. Respiration - Which kingdom includes multicellular organisms with chitin cell wall?
A. Plantae
B. Fungi
C. Protista
D. Monera - Crossing over occurs during:
A. Prophase I
B. Metaphase I
C. Anaphase II
D. Telophase II - Which structure prevents backflow of blood in veins?
A. Septa
B. Valves
C. Nodes
D. Capillaries - The sequence of amino acids in proteins is determined by:
A. Lipids
B. DNA sequence
C. Vitamins
D. ATP - Which type of immunity develops after vaccination?
A. Passive natural
B. Passive artificial
C. Active artificial
D. Active natural - The blood filtration process in kidney occurs in:
A. Bowman’s capsule
B. Collecting duct
C. Loop of Henle
D. Ureter - Which hormone prepares the body for emergencies?
A. Insulin
B. Estrogen
C. Adrenaline
D. Thyroxine - What is the role of tRNA in protein synthesis?
A. Carries amino acids
B. Forms ribosomes
C. Replicates DNA
D. Stores energy - The exchange of genetic material between homologous chromosomes is:
A. Mutation
B. Replication
C. Crossing over
D. Translation - Which part of the nephron is mainly responsible for reabsorption?
A. Glomerulus
B. Bowman’s capsule
C. Tubules
D. Ureter - Which ecological relationship benefits both organisms?
A. Parasitism
B. Predation
C. Mutualism
D. Competition - In DNA replication, the enzyme responsible for joining Okazaki fragments is:
A. Helicase
B. Ligase
C. Primase
D. Polymerase - The oxygen released during photosynthesis comes from:
A. Carbon dioxide
B. Glucose
C. Water
D. Chlorophyll - Which phase of meiosis reduces chromosome number by half?
A. Prophase II
B. Metaphase II
C. Anaphase I
D. Telophase II - Which blood component transports oxygen?
A. Plasma
B. Platelets
C. Hemoglobin
D. Lymph - The site of light reaction in chloroplast is:
A. Stroma
B. Thylakoid membrane
C. Matrix
D. Cytoplasm - Which scientist gave the cell theory?
A. Schleiden and Schwann
B. Watson and Crick
C. Darwin and Wallace
D. Mendel and Morgan - Which hormone controls water balance in the body?
A. Growth hormone
B. ADH
C. Insulin
D. Thyroxine - The codon AUG codes for:
A. Stop signal
B. Methionine
C. Glycine
D. Leucine - The part of brain controlling involuntary actions is:
A. Cerebellum
B. Medulla oblongata
C. Hypothalamus
D. Cerebrum - Which vessel has the thickest walls?
A. Capillary
B. Vein
C. Artery
D. Venule - A person with genotype IAIB has blood group:
A. A
B. B
C. O
D. AB - The lac operon is associated with:
A. Photosynthesis
B. Respiration
C. Gene regulation
D. Digestion - Which structure is responsible for spindle formation in animal cells?
A. Ribosome
B. Centriole
C. Vacuole
D. Chloroplast - The Calvin cycle occurs in:
A. Cytoplasm
B. Grana
C. Stroma
D. Mitochondria - Which type of RNA carries genetic message from DNA to ribosome?
A. rRNA
B. tRNA
C. mRNA
D. snRNA - The process by which bacteria take up external DNA is called:
A. Translation
B. Transformation
C. Transduction
D. Conjugation - Which structure in flowers produces pollen grains?
A. Ovule
B. Style
C. Anther
D. Ovary - During glycolysis, glucose is converted into:
A. Acetyl CoA
B. Pyruvate
C. Lactate
D. Ethanol - The smallest taxonomic unit is:
A. Genus
B. Species
C. Family
D. Order - Which component of plasma membrane provides fluidity?
A. Proteins
B. Cholesterol
C. Carbohydrates
D. Cellulose - In Hardy-Weinberg equilibrium, evolution does not occur when:
A. Mutations occur
B. Population is small
C. Random mating occurs
D. Natural selection acts - The enzyme RuBisCO functions in:
A. Glycolysis
B. Krebs cycle
C. Calvin cycle
D. Fermentation - Which process directly produces ATP in mitochondria?
A. Fermentation
B. Electron transport chain
C. Glycolysis
C. Photolysis - A mutation involving addition or deletion of nucleotides is called:
A. Silent mutation
B. Frameshift mutation
C. Point mutation
D. Inversion - Which hormone stimulates ovulation in females?
A. FSH
B. LH
C. Prolactin
D. Oxytocin - The immune response involving antibodies is mediated by:
A. T lymphocytes
B. Neutrophils
C. B lymphocytes
D. Macrophages - Which type of succession starts on bare rocks?
A. Secondary succession
B. Primary succession
C. Aquatic succession
D. Cyclic succession - The semiconservative model of DNA replication was proven by:
A. Watson and Crick
B. Hershey and Chase
C. Meselson and Stahl
C. Mendel and Morgan - Which event occurs during anaphase of mitosis?
A. Chromosomes align at equator
B. Nuclear membrane disappears
C. Sister chromatids separate
D. Cytokinesis occurs - The movement of substances through a membrane using carrier proteins without energy is:
A. Active transport
B. Facilitated diffusion
C. Endocytosis
D. Exocytosis