Biology MCQs: Here are 100 Multiple Choice Questions (MCQs) about Biology, divided into categories such as Cell Biology, Human Body, Genetics, Ecology, and more. The correct answers are marked with (Correct).
🧬 Cell Biology
-
Which organelle is known as the “powerhouse of the cell”?
a) Nucleus
b) Mitochondria (Correct)
c) Ribosome
d) Golgi apparatus -
The basic unit of life is:
a) Atom
b) Molecule
c) Cell (Correct)
d) Organelle -
Which structure controls what enters and leaves the cell?
a) Nucleus
b) Cell membrane (Correct)
c) Cytoplasm
d) Mitochondria -
Which organelle is responsible for protein synthesis?
a) Ribosome (Correct)
b) Lysosome
c) Golgi body
d) Endoplasmic reticulum -
The jelly-like substance inside the cell is called:
a) Nucleoplasm
b) Cytoplasm (Correct)
c) Mitochondria
d) Vacuole
🧠 Human Body and Physiology
-
What is the largest organ in the human body?
a) Heart
b) Liver
c) Skin (Correct)
d) Brain -
The functional unit of the kidney is:
a) Alveoli
b) Nephron (Correct)
c) Neuron
d) Glomerulus -
Which blood cells help in clotting?
a) RBCs
b) WBCs
c) Platelets (Correct)
d) Plasma -
Which system is responsible for transporting blood?
a) Respiratory system
b) Circulatory system (Correct)
c) Digestive system
d) Nervous system -
The part of the brain responsible for balance is:
a) Cerebrum
b) Medulla
c) Cerebellum (Correct)
d) Hypothalamus
🌱 Botany
-
The process of converting light energy into chemical energy in plants is:
a) Respiration
b) Transpiration
c) Photosynthesis (Correct)
d) Digestion -
The green pigment in plants is called:
a) Hemoglobin
b) Chlorophyll (Correct)
c) Xanthophyll
d) Melanin -
Which part of the plant absorbs water and nutrients?
a) Stem
b) Leaves
c) Roots (Correct)
d) Flowers -
What is the reproductive part of the plant?
a) Root
b) Leaf
c) Flower (Correct)
d) Stem -
Plants make their food in the:
a) Roots
b) Stem
c) Leaves (Correct)
d) Flowers
🧬 Genetics
-
Genes are located on:
a) Ribosomes
b) Chromosomes (Correct)
c) Cytoplasm
d) Mitochondria -
The father of genetics is:
a) Charles Darwin
b) Alexander Fleming
c) Gregor Mendel (Correct)
d) Louis Pasteur -
DNA stands for:
a) Deoxyribonucleic acid (Correct)
b) Dinucleic acid
c) Dinitrogen acid
d) Deoxyribose acid -
The shape of DNA is:
a) Straight line
b) Double helix (Correct)
c) Spiral square
d) Circle -
Mutation is a:
a) Normal reproduction
b) Change in DNA sequence (Correct)
c) Cell division
d) Protein synthesis
🦠 Microbiology
-
Microorganisms can be seen with the help of:
a) Naked eye
b) Telescope
c) Microscope (Correct)
d) Spectacles -
Which of these causes tuberculosis?
a) Virus
b) Fungus
c) Bacteria (Correct)
d) Protozoa -
Louis Pasteur is known for discovering:
a) Evolution
b) Pasteurization (Correct)
c) Vaccination
d) Penicillin -
Penicillin was discovered by:
a) Gregor Mendel
b) Alexander Fleming (Correct)
c) Louis Pasteur
d) Robert Koch -
HIV is a type of:
a) Bacteria
b) Virus (Correct)
c) Fungus
d) Protozoa
🧫 Cell Division
-
The type of cell division in somatic cells is:
a) Meiosis
b) Binary fission
c) Mitosis (Correct)
d) Budding -
Meiosis occurs in:
a) Liver cells
b) Kidney cells
c) Reproductive cells (Correct)
d) Skin cells -
Mitosis results in:
a) 2 identical cells (Correct)
b) 4 different cells
c) 1 half cell
d) 1 mutated cell -
Crossing over occurs in:
a) Mitosis
b) Meiosis I (Correct)
c) Meiosis II
d) Cytokinesis -
The longest phase of the cell cycle is:
a) Anaphase
b) Telophase
c) Interphase (Correct)
d) Metaphase
🌍 Ecology and Environment
-
Which gas do plants absorb from the atmosphere?
a) Oxygen
b) Carbon dioxide (Correct)
c) Nitrogen
d) Helium -
The ozone layer protects us from:
a) Acid rain
b) UV radiation (Correct)
c) Dust
d) Sound pollution -
Deforestation leads to:
a) Increase in rainfall
b) Global warming (Correct)
c) More oxygen
d) Cleaner air -
A food chain always starts with:
a) Herbivore
b) Carnivore
c) Decomposer
d) Producer (Correct) -
Organisms that break down dead material are called:
a) Producers
b) Consumers
c) Decomposers (Correct)
d) Herbivores
🧠 Nervous System and Senses
-
The brain and spinal cord make up the:
a) Peripheral nervous system
b) Central nervous system (Correct)
c) Somatic nervous system
d) Sympathetic nervous system -
The largest part of the human brain is:
a) Cerebellum
b) Medulla
c) Cerebrum (Correct)
d) Thalamus -
The sense organ for hearing is:
a) Eye
b) Nose
c) Tongue
d) Ear (Correct) -
Which part of the eye controls the amount of light entering?
a) Retina
b) Iris (Correct)
c) Cornea
d) Lens -
Reflex actions are controlled by the:
a) Brain
b) Spinal cord (Correct)
c) Eyes
d) Nerves
🧃 Nutrition and Digestion
-
The process of breaking down food is called:
a) Respiration
b) Digestion (Correct)
c) Circulation
d) Absorption -
The enzyme that digests starch is:
a) Lipase
b) Amylase (Correct)
c) Pepsin
d) Trypsin -
Bile is produced in the:
a) Pancreas
b) Liver (Correct)
c) Stomach
d) Gallbladder -
The main site for absorption of nutrients is:
a) Stomach
b) Small intestine (Correct)
c) Large intestine
d) Esophagus -
Which vitamin is made in the skin when exposed to sunlight?
a) Vitamin A
b) Vitamin C
c) Vitamin D (Correct)
d) Vitamin K
🦴 Skeletal and Muscular System
-
The human body has how many bones?
a) 206 (Correct)
b) 208
c) 210
d) 200 -
The longest bone in the body is:
a) Tibia
b) Humerus
c) Femur (Correct)
d) Radius -
The smallest bone is found in the:
a) Nose
b) Ear (Correct)
c) Toe
d) Hand -
Muscles are attached to bones by:
a) Ligaments
b) Tendons (Correct)
c) Cartilage
d) Nerves -
Which mineral is most important for bones?
a) Iron
b) Sodium
c) Potassium
d) Calcium (Correct)
🧬 Reproduction and Development
-
The union of sperm and egg is called:
a) Fertilization (Correct)
b) Ovulation
c) Menstruation
d) Reproduction -
The organ where a baby develops in the mother is the:
a) Ovary
b) Uterus (Correct)
c) Vagina
d) Fallopian tube -
In humans, fertilization normally takes place in the:
a) Ovary
b) Uterus
c) Fallopian tube (Correct)
d) Cervix -
The male reproductive cell is called:
a) Egg
b) Zygote
c) Sperm (Correct)
d) Embryo -
Asexual reproduction involves:
a) Two parents
b) One parent (Correct)
c) Gametes
d) Fertilization
🧪 Biomolecules
-
Proteins are made up of:
a) Sugars
b) Fatty acids
c) Amino acids (Correct)
d) Nucleotides -
The main source of energy for the human body is:
a) Proteins
b) Carbohydrates (Correct)
c) Fats
d) Vitamins -
Enzymes act as:
a) Hormones
b) Catalysts (Correct)
c) Pigments
d) Acids -
The building blocks of DNA are:
a) Sugars
b) Bases
c) Nucleotides (Correct)
d) Peptides -
Fats are also known as:
a) Lipids (Correct)
b) Amino acids
c) Nucleic acids
d) Starches
🌾 Classification and Taxonomy
-
The science of classification is called:
a) Ecology
b) Taxonomy (Correct)
c) Anatomy
d) Cytology -
The largest taxonomic category is:
a) Genus
b) Family
c) Kingdom (Correct)
d) Order -
Humans belong to which kingdom?
a) Plantae
b) Animalia (Correct)
c) Fungi
d) Protista -
Binomial nomenclature uses:
a) One name
b) Two names (Correct)
c) Three names
d) Latin symbols -
The first part of the scientific name is the:
a) Species
b) Family
c) Genus (Correct)
d) Order
🐠 Evolution and Adaptation
-
The theory of natural selection was proposed by:
a) Mendel
b) Darwin (Correct)
c) Pasteur
d) Lamarck -
Evolution is the change in organisms over:
a) A few years
b) Generations (Correct)
c) Days
d) Months -
The evidence of evolution is found in:
a) Bones
b) Fossils (Correct)
c) Muscles
d) Nerves -
The wings of a bat and the wings of a bird are:
a) Analogous structures (Correct)
b) Homologous structures
c) Identical structures
d) Evolved from insects -
Giraffes having long necks is an example of:
a) Adaptation (Correct)
b) Mutation
c) Fossilization
d) Inheritance
🌡️ Health and Diseases
-
Malaria is caused by:
a) Bacteria
b) Virus
c) Protozoa (Correct)
d) Fungus -
Which vitamin prevents rickets?
a) Vitamin A
b) Vitamin C
c) Vitamin D (Correct)
d) Vitamin K -
Diabetes is caused due to lack of:
a) Insulin (Correct)
b) Glucose
c) Hemoglobin
d) Vitamin C -
The disease AIDS is caused by:
a) Bacteria
b) Virus (Correct)
c) Protozoa
d) Fungus -
Which disease is prevented by the BCG vaccine?
a) Polio
b) Measles
c) Tuberculosis (Correct)
d) Chickenpox
🌊 Biology in Everyday Life
-
Which of these is biodegradable?
a) Plastic
b) Glass
c) Banana peel (Correct)
d) Metal -
Which organism is used in alcohol production?
a) Amoeba
b) Yeast (Correct)
c) Fungi
d) Bacteria -
Insulin is produced in the:
a) Liver
b) Pancreas (Correct)
c) Kidney
d) Brain -
Photosynthesis occurs in:
a) Animals
b) Humans
c) Plants (Correct)
d) Fungi -
Blood is a:
a) Tissue
b) Organ
c) Fluid connective tissue (Correct)
d) Enzyme
🐦 Animal Biology and Behavior
-
Birds have:
a) Scales
b) Gills
c) Feathers (Correct)
d) Hair -
The breathing organ of fish is:
a) Nose
b) Lungs
c) Gills (Correct)
d) Skin -
The largest mammal is the:
a) Elephant
b) Blue whale (Correct)
c) Giraffe
d) Tiger -
A baby frog is called a:
a) Cub
b) Tadpole (Correct)
c) Calf
d) Nymph -
Animals that eat only plants are called:
a) Carnivores
b) Omnivores
c) Herbivores (Correct)
d) Scavengers
📊 Miscellaneous
-
The study of life is called:
a) Chemistry
b) Biology (Correct)
c) Physics
d) Botany -
Blood is red due to:
a) Plasma
b) Hemoglobin (Correct)
c) White blood cells
d) Platelets -
Which part of the plant conducts photosynthesis?
a) Root
b) Leaf (Correct)
c) Stem
d) Flower -
Human beings have how many chromosomes in total?
a) 23
b) 46 (Correct)
c) 24
d) 48 -
The process by which cells become specialized is called:
a) Division
b) Differentiation (Correct)
c) Diffusion
d) Replication -
The smallest unit of heredity is:
a) Chromosome
b) DNA
c) Gene (Correct)
d) Cell -
What causes rusting in plants?
a) Fungi (Correct)
b) Bacteria
c) Virus
d) Algae -
Which part of the brain controls heartbeat and breathing?
a) Cerebrum
b) Cerebellum
c) Medulla (Correct)
d) Thalamus -
An organism that feeds on dead material is a:
a) Herbivore
b) Scavenger (Correct)
c) Predator
d) Omnivore -
Insects breathe through:
a) Lungs
b) Gills
c) Spiracles (Correct)
d) Nose -
Which vitamin is essential for blood clotting?
a) A
b) C
c) D
d) K (Correct) -
Which gland produces adrenaline?
a) Pituitary
b) Thyroid
c) Adrenal (Correct)
d) Pancreas -
Which blood group is called the universal donor?
a) A
b) B
c) AB
d) O (Correct) -
Who proposed the binomial nomenclature system?
a) Darwin
b) Linnaeus (Correct)
c) Mendel
d) Lamarck -
The structural and functional unit of the nervous system is:
a) Brain
b) Neuron (Correct)
c) Muscle
d) Gland
