NEET bio Test Series 2025 Leave a Comment / By Vishal singh / March 20, 2025 Welcome to your NEET bio Test Series 2025Which of the following is the function of the smooth endoplasmic reticulum (SER)? a) Protein synthesis b) Lipid and steroid synthesis c) Transport of proteins d) Detoxification None The process of programmed cell death (apoptosis) is controlled by the release of cytochrome c from the a) Lysosomes b) Mitochondria c) Golgi apparatus d) Nucleus None The process by which a single-stranded RNA virus is converted to double-stranded DNA is called a) Transcription b) Translation c) Reverse transcription d) Replication None In a population of rabbits, the frequency of a recessive allele for a coat color trait is 0.2. The expected frequency of heterozygotes under Hardy-Weinberg equilibrium is a) 0.32 b) 0.16 c) 0.4 d) 0.6 None If the allele for a particular gene is represented by A, the heterozygous individual would have the genotype a) AA b) Aa c) aa d) None of the above None The process by which homologous chromosomes exchange segments of chromatids during meiosis is called a) Crossing over b) Independent assortment c) Mutation d) Segregation None The primary function of the alveoli in the lungs is a) Filtering out bacteria b) Absorption of oxygen and release of carbon dioxide c) Production of surfactant d) Transport of gases through the blood None The hormone responsible for the reabsorption of sodium in the kidneys is a) Insulin b) Aldosterone c) Thyroxine d) Glucagon None Which of the following is NOT a function of auxins in plants? a) Promote cell elongation b) Inhibit leaf abscission c) Inhibit root growth d) Promote fruit ripening None The term 'carrying capacity' in an ecosystem refers to a) The maximum population size an environment can support b) The amount of food available to an organism c) The capacity of an organism to reproduce d) The number of trophic levels in a food chain None In human males, the primary function of the Sertoli cells is a) Spermatogenesis b) Secretion of testosterone c) Secretion of inhibin d) Nourishment of developing sperm None In humans, fertilization usually occurs in the a) Ovaries b) Uterus c) Fallopian tubes d) Cervix None The first genetically modified (GM) crop was a) Cotton b) Rice c) Tomato d) Maize None Which of the following techniques is used to amplify specific DNA sequences? a) PCR (Polymerase Chain Reaction) b) Gel electrophoresis c) DNA fingerprinting d) Restriction enzyme analysis None In recombinant DNA technology, the vector used to transfer genes into plant cells is typically a) Plasmids b) Viruses c) Agrobacterium d) All of the above None The causative agent of tuberculosis (TB) is a) Mycobacterium tuberculosis b) Streptococcus pneumoniae c) Staphylococcus aureus d) Escherichia coli None Which of the following vaccines is used to prevent the disease caused by the bacterium Clostridium tetani? a) MMR vaccine b) DTP vaccine c) BCG vaccine d) HPV vaccine None Which of the following cell organelles contains its own DNA and is responsible for cellular respiration? a) Mitochondria b) Nucleus c) Ribosome d) Chloroplast None In a dihybrid cross between two heterozygous individuals, what will be the phenotypic ratio of the offspring? a) 1:1 b) 9:3:3:1 c) 3:1 d) 1:2:1 None Which part of the brain regulates the autonomic nervous system, including heart rate and blood pressure? a) Cerebrum b) Cerebellum c) Hypothalamus d) Medulla oblongata None In C4 plants, carbon dioxide is initially fixed into a 4-carbon compound in the a) Mesophyll cells b) Bundle sheath cells c) Xylem d) Phloem None Which of the following biomes is characterized by cold winters and short summers with low precipitation? a) Tropical rainforest b) Tundra c) Desert d) Grassland None Which of the following is used as a vector for gene transfer in plants? a) Plasmids b) Agrobacterium c) Viruses d) Both b and c None Which of the following is NOT caused by a virus? a) Smallpox b) Influenza c) Tuberculosis d) Measles None Which part of the nervous system is responsible for voluntary muscle movements? a) Sympathetic nervous system b) Parasympathetic nervous system c) Somatic nervous system d) Autonomic nervous system None A cross between a homozygous dominant individual and a homozygous recessive individual results in the following F1 generation: Aa. What is the expected phenotypic ratio of the F2 generation? a) 3:1 b) 1:1 c) 1:2:1 d) 4:0 None In C3 plants, the enzyme responsible for the fixation of carbon dioxide in the Calvin cycle is a) RuBisCO b) PEP carboxylase c) NADP reductase d) ATP synthase None In the trophic levels of an ecosystem, the energy transfer efficiency between each level is generally a) 100% b) 50% c) 10% d) 1% None Which of the following biogeochemical cycles is driven by bacterial processes? a) Nitrogen cycle b) Water cycle c) Carbon cycle d) Oxygen cycle None In a test cross, a heterozygous tall plant is crossed with a homozygous recessive short plant. The expected phenotypic ratio of the offspring is a) 3:1 b) 1:1 c) 4:0 d) 2:2 None Which of the following is the primary function of the nephron in the kidney? a) Secretion of insulin b) Filtration of blood to form urine c) Regulation of body temperature d) Storage of urine None The heart sounds (lub-dub) are caused by the a) Contraction of the ventricles b) Closing of the atrioventricular and semilunar valves c) Opening of the atrioventricular and semilunar valves d) Flow of blood through the coronary arteries None Which of the following structures is involved in the formation of the blastocyst in humans? a) Zygote b) Morula c) Blastula d) Gastrula None Which technique is used to separate DNA fragments based on their size? a) Gel electrophoresis b) PCR c) DNA hybridization d) Southern blotting None Which of the following viruses is primarily responsible for causing the disease known as acquired immunodeficiency syndrome (AIDS)? a) Hepatitis B virus b) Human papillomavirus c) Human immunodeficiency virus d) Influenza virus None In a case of incomplete dominance, the phenotype of the heterozygous offspring will be a) The same as the dominant allele b) The same as the recessive allele c) A blend of the two alleles d) A mixture of both homozygous phenotypes None Which structure in the human heart prevents the backflow of blood from the right ventricle into the right atrium? a) Tricuspid valve b) Pulmonary valve c) Aortic valve d) Mitral valve None In which part of the human digestive system does the majority of nutrient absorption occur? a) Mouth b) Stomach c) Small intestine d) Large intestine None The pressure-flow hypothesis explains the movement of a) Water through the plant b) Sugars in the phloem c) Ions across cell membranes d) Oxygen in the xylem None A keystone species is defined as a species that a) Has the highest population in an ecosystem b) Plays a critical role in maintaining the structure of an ecosystem c) Is the top predator in the food chain d) Is the most abundant species in an ecosystem None The enzyme responsible for synthesizing the RNA primer in DNA replication is a) DNA polymerase I b) RNA polymerase c) Primase d) Ligase None Which of the following immunoglobulins is the first to be produced in response to an infection? a) IgG b) IgM c) IgA d) IgE None Which of the following cells are primarily responsible for initiating an adaptive immune response? a) Macrophages b) B-cells c) T-helper cells d) Cytotoxic T-cells None The primary function of aldosterone is to a) Increase blood glucose levels b) Regulate calcium metabolism c) Increase sodium reabsorption in the kidneys d) Stimulate protein synthesis None Which neurotransmitter is primarily associated with muscle contraction at the neuromuscular junction? a) Dopamine b) Acetylcholine c) Serotonin d) GABA None In cellular respiration, the final electron acceptor in the electron transport chain is a) ATP b) Oxygen c) NAD+ d) FADH2 None Which of the following hormones is responsible for maintaining the corpus luteum after ovulation? a) Estrogen b) FSH c) LH d) Progesterone None The causative agent of tuberculosis is a) Plasmodium b) Mycobacterium tuberculosis c) Salmonella d) Streptococcus None The removal of introns and joining of exons during mRNA processing is called a) Splicing b) Capping c) Translation d) Transcription None Which type of MHC (Major Histocompatibility Complex) is found on all nucleated cells? a) MHC I b) MHC II c) MHC III d) T-cell Receptor None Which ion is primarily responsible for repolarization during an action potential? a) Sodium (Na⁺) b) Calcium (Ca²⁺) c) Potassium (K⁺) d) Chloride (Cl⁻) None The first stable product of the Hatch-Slack (C4) pathway is a) PGA b) Malate c) Oxaloacetic acid d) RuBP None Which of the following steps in the carbon cycle is primarily carried out by decomposers? a) Photosynthesis b) Carbon fixation c) Respiration d) Decomposition None Which of the following is the site of fertilization in humans? a) Ovary b) Uterus c) Cervix d) Fallopian Tube None Which of the following best describes the Founder Effect in evolution? a) A sudden decrease in population size due to a natural disaster b) Genetic variation decreases due to selective breeding c) A small group from a population establishes a new colony, leading to reduced genetic diversity d) The emergence of new traits due to beneficial mutations None Which of the following processes releases sulfur into the atmosphere in the form of hydrogen sulfide (H₂S)? a) Nitrification b) Sulfate reduction c) Decomposition d) Sulfur assimilation None Which viral vector is commonly used for gene therapy applications due to its ability to integrate into the host genome? a) Adenovirus b) Retrovirus c) Lentivirus d) Baculovirus None Which factor is primarily responsible for initiating the cardiac action potential? a) Atrioventricular (AV) node b) Purkinje fibers c) Sinoatrial (SA) node d) Bundle of His None Which of the following secondary metabolites plays a key role in plant defense against herbivores? a) Gibberellins b) Alkaloids c) Cytokinins d) Flavonoids None Which of the following secondary metabolites plays a key role in plant defense against herbivores? a) Gibberellins b) Alkaloids c) Cytokinins d) Flavonoids None Name Email Time's upTime is Up!
