List of Biology Vocabulary words and definitions. It covers a large range of biological concepts from cells and organisms to genetics and ecosystems. It is best for students, educators, and anyone interested in understanding basic biological concepts.
Table of Contents
ToggleBiology Vocabulary Words List A-Z
Here is the list of biology vocabulary words from A to Z with definitions:
A
Adaptation: A trait that helps an organism survive in its environment
Amino acid: The building blocks of proteins
Antibody: A protein produced by the immune system to fight pathogens
ATP: Adenosine triphosphate, the energy currency of cells
Autotroph: An organism that can produce its food
B
Bacteria: Single-celled microorganisms without a nucleus
Biodiversity: The variety of life in a particular habitat or ecosystem
Biome: A large naturally occurring community of flora and fauna
Biotechnology: The use of living systems and organisms to develop products
Botany: The scientific study of plants
C
Cell: The basic structural and functional unit of all living organisms
Chromosome: A structure of nucleic acids and protein found in the nucleus of most living cells
Cytoplasm: The material within a living cell, excluding the nucleus
Chlorophyll: Green pigment in plants that absorbs light for photosynthesis
Commensalism: A relationship between two organisms where one benefits and the other is unaffected
D
DNA: The molecule that carries genetic instructions in all living things
Digestion: The process of breaking down food into smaller parts the body can use
Dominant: A trait that shows up even if only one copy of the gene is present
Dormancy: A period when an organism’s growth and development slow down or stop
Decomposer: An organism that breaks down dead plant and animal matter
E
Ecosystem: A community of living things and their environment
Endocrine system: The body system that uses hormones to control various functions
Evolution: The process by which living things change over time
Experiment: A scientific test to study what happens under certain conditions
Enzyme: A protein that speeds up chemical reactions in living things
F
Fertilization: The joining of male and female sex cells
Food chain: A series of organisms each dependent on the next for food
Fossil: The remains or impression of a prehistoric plant or animal
Fungi: A group of living things that are not plants or animals, like mushrooms
Fermentation: A process where sugars are broken down without oxygen
G
Gene: A part of DNA that controls a specific trait
Genetics: The study of how traits are passed from parents to offspring
Glucose: A simple sugar that is an important energy source for living things
Growth: An increase in size or amount
Gamete: A reproductive cell (egg or sperm)
H
Habitat: The natural home or environment of an animal, plant, or other organism
Heredity: The passing of traits from parents to their offspring
Homeostasis: The ability to maintain a stable internal environment
Hormone: A chemical messenger in the body
Host: An organism that provides food or shelter for another organism
I
Immunity: The body’s ability to resist diseases
Inheritance: The passing of genetic information from parent to offspring
Invertebrate: An animal without a backbone
Ion: An atom or molecule with an electric charge
Instinct: A natural behavior that an animal is born with
J
Juvenile: A young animal that has not reached adulthood
Joint: A place where two bones meet in the body
Jelly: A clear, thick liquid found in some animal cells
K
Kidney: An organ that filters blood and removes waste from the body
Kingdom: The highest rank used to classify living things
Karyotype: A picture of an organism’s chromosomes
L
Life cycle: The stages through which an organism passes during its lifetime
Lipid: A type of molecule that includes fats and oils
Lymph: A clear fluid that carries white blood cells through the body
Larva: An immature form of some animals before they change into adults
Leaf: The main part of a plant that makes food through photosynthesis
M
Metabolism: All the chemical reactions that happen in a living thing
Mitosis: The process of cell division
Mutation: A change in DNA
Microorganism: A living thing too small to see without a microscope
Molecule: A group of atoms bonded together
N
Neuron: A nerve cell that sends and receives messages in the body
Nucleus: The control center of a cell
Nutrient: A substance that provides nourishment for growth
Natural selection: The process by which organisms better adapted to their environment tend to survive
Niche: The role an organism plays in its ecosystem
O
Organ: A part of the body with a specific function
Osmosis: The movement of water through a membrane
Offspring: The young of an animal or plant
Oxygen: A gas needed by most living things to survive
Organelle: A tiny structure inside a cell with a specific job
P
Photosynthesis: The process by which plants make food using sunlight
Predator: An animal that hunts and eats other animals
Protein: A large molecule made of amino acids, important for body structure and function
Parasite: An organism that lives on or in another organism and harms it
Pollen: Tiny grains produced by plants for reproduction
Q
Quadruped: An animal that walks on four legs
Qualitative: Based on qualities rather than quantities
Quantitative: Based on amounts or numbers
R
Reproduction: The process by which living things make more of their own kind
Respiration: The process of taking in oxygen and releasing carbon dioxide
RNA: A molecule similar to DNA that helps make proteins
Recessive: A trait that only shows up if both copies of the gene are present
Root: The part of a plant that grows underground and absorbs water and nutrients
S
Species: A group of living things that can reproduce with each other
Stimulus: Something that causes a response in an organism
Symbiosis: A close relationship between two different species
Stem: The main support of a plant, which carries water and nutrients
Spore: A small reproductive body produced by some plants and fungi
T
Tissue: A group of similar cells working together
Taxonomy: The science of naming and classifying living things
Trait: A characteristic of an organism
Toxin: A poisonous substance produced by living things
Transpiration: The process of water movement through a plant and its evaporation from leaves
U
Unicellular: Made of only one cell
Umbilical cord: The cord connecting a fetus to the placenta
UV radiation: Invisible light rays from the sun that can damage skin
V
Vacuole: A space or bubble in a cell used for storage
Vertebrate: An animal with a backbone
Virus: A tiny particle that can infect living cells
Vein: A blood vessel that carries blood back to the heart
Vitamin: A nutrient needed in small amounts for good health
W
White blood cell: A cell in the blood that helps fight disease
Water cycle: The continuous movement of water on Earth
Waste: Unwanted or unused material produced by living things
X
X-ray: A type of radiation used to see inside the body
Xylem: Plant tissue that carries water and nutrients upward from the roots
Y
Yeast: A tiny fungus used in baking and brewing
Y chromosome: The chromosome that determines male sex in many animals
Z
Zygote: A fertilized egg cell
Zoology: The study of animals
Zonation: The distribution of plants and animals in distinct zones or areas