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Biology Dictionary
Learn
Concepts
Cell
Biochemistry
Human
Genetics
Zoology
Botany
Ecology
Anatomy & Physiology
Molecular
Microbiology
Neuroscience
Animal Kingdom
Trending Topics
Study Guides
High School
Middle School (coming soon!)
Elementary School (coming soon!)
News & Stories
Latest News
Editors’ Pick
Weekly Digest
Fun
Quotes
Teaching Resources
Cell Biology
Abiogenesis
January 31, 2017
Abiotic Factors
October 18, 2016
Active Immunity
November 18, 2016
Active Site
October 20, 2016
Active Transport
October 20, 2016
Adenosine Triphosphate (ATP)
January 20, 2017
Adhesion
October 23, 2016
Aerobic Respiration
October 23, 2016
Agonist
May 15, 2017
Aldosterone
June 18, 2019
Allele
December 4, 2016
Allele Frequency
December 4, 2016
Amino Acids
January 9, 2020
Amnion
June 2, 2017
Amoeba
May 5, 2017
Anabolism
February 13, 2017
Anaerobic Organism
June 9, 2017
Anaerobic Respiration
October 27, 2016
Anaphase
December 21, 2016
Anaphase I
May 29, 2019
Anaplasia
November 12, 2016
Animal Cell
April 4, 2017
Antibody
April 22, 2018
Anticodon
October 30, 2016
Antioxidant
May 2, 2017
Apoptosis
June 6, 2017
Archaebacteria
November 5, 2016
Articular Cartilage
April 26, 2019
ATP Synthase
February 22, 2017
Autophagy
June 8, 2017
Autosomes
November 5, 2016
Autotroph
November 8, 2016
Bacteria
March 19, 2017
Barr Body
March 19, 2017
Base Pair
May 16, 2017
Beta Oxidation
June 2, 2017
Bile Salts
November 20, 2019
Bilirubin
April 1, 2018
Binary Fission
January 11, 2017
Biochemistry
May 2, 2017
Biophysics
July 30, 2017
Biopsy
May 26, 2017
Biotic Factors
November 8, 2016
Blastocyst
June 14, 2017
Calmodulin
June 25, 2017
Calvin Cycle
November 10, 2016
CAM Plants
November 11, 2016
Carbonyl Group
April 5, 2017
Carboxyl Group
February 21, 2017
Carcinoma
June 12, 2017
Cardiac Muscle
December 8, 2017
Carrier Protein
November 15, 2016
Cartilage
April 25, 2019
Catabolism
January 11, 2017
Cell
November 15, 2016
Cell Culture
May 7, 2017
Cell Cycle
May 30, 2017
Cell Differentiation
June 20, 2018
Cell Division
December 15, 2016
Cell Membrane
March 13, 2017
Cell Nucleus
July 30, 2017
Cell Plate
November 17, 2016
Cell Signaling
May 4, 2017
Cell Theory
December 15, 2016
Cell Wall
March 19, 2017
Cellular Respiration
November 17, 2016
Cellular Senescence
May 26, 2017
Central Vacuole
April 5, 2017
Centriole
January 27, 2017
Centromere
November 26, 2016
Centrosome
January 14, 2017
Channel Protein
June 20, 2018
Chemical Biology
April 27, 2017
Chemiosmosis
February 13, 2017
Chemoautotroph
December 10, 2016
Chemoheterotroph
December 16, 2016
Chemokines
July 4, 2017
Chemosynthesis
March 20, 2017
Chitin
January 13, 2017
Chlorophyll
December 10, 2016
Chloroplast
March 19, 2017
Chromatid
December 16, 2016
Chromosome
December 13, 2016
Cilium
June 25, 2017
Cleavage Furrow
December 20, 2016
Coenzyme
November 15, 2016
Cofactor
February 21, 2017
Compact Bone
February 27, 2017
Concentration Gradient
January 10, 2017
Condensation
February 28, 2017
Control Group
December 15, 2016
Controlled Experiment
February 12, 2017
Creatine Kinase
May 13, 2018
Crenation
November 12, 2016
Cricoid Cartilage
April 26, 2019
CRISPR
April 27, 2017
Cristae
November 23, 2016
Crossing Over
December 6, 2016
Curare
February 20, 2017
Cytokinesis
December 21, 2016
Cytolysis
December 13, 2016
Cytoplasm
December 13, 2016
Cytoskeleton
April 5, 2017
Cytosol
March 20, 2017
Daughter Cells
October 25, 2018
Dehydration Synthesis
December 17, 2016
Deletion Mutation
February 20, 2017
Denature
December 18, 2016
Dendrite
June 3, 2017
Deoxyribose
February 9, 2017
Desmosomes
April 14, 2017
Deuterostome
April 14, 2017
Diatom
January 21, 2018
Diffusion
April 27, 2017
Diploid
January 7, 2018
Disaccharide
January 10, 2017
DNA
May 27, 2017
DNA Sequencing
June 23, 2017
Domain
April 17, 2019
Dominant Allele
December 6, 2016
Dynamic Equilibrium
February 9, 2017
Ectoderm
June 9, 2017
Ectotherm
February 26, 2018
Elastic Cartilage
April 26, 2019
Electron Transport Chain
November 10, 2016
Embryo
July 4, 2017
Embryonic Stem Cells
March 15, 2018
Emulsify
November 24, 2016
Endergonic Reaction
May 2, 2017
Endocytosis
November 15, 2016
Endoderm
June 9, 2017
Endoplasmic Reticulum
January 27, 2017
Endosymbiotic Theory
February 10, 2017
Enzyme Substrate Complex
December 4, 2016
Epistasis
November 22, 2016
Epithelial Tissue
December 25, 2016
Equilibrium Constant
February 21, 2017
Eubacteria
November 25, 2016
Euchromatin
June 13, 2017
Eukaryote
December 13, 2016
Eukaryotic Cell
December 6, 2016
Exergonic Reaction
May 2, 2017
Exocrine Glands
April 27, 2017
Exon
August 6, 2017
Experimental Group
December 21, 2016
External Respiration
February 12, 2017
Extracellular Fluid
February 14, 2017
Extracellular Matrix
September 8, 2017
Facilitated Diffusion
April 5, 2017
Facultative Anaerobe
October 7, 2018
Fat
May 7, 2017
Fatty Acids
May 5, 2017
Feedback Inhibition
February 12, 2017
Fertilization
December 4, 2016
Filtration
March 3, 2017
Flagellum
March 24, 2017
Flow Cytometry
May 14, 2017
Fluid Mosaic Model
April 5, 2017
Food Vacuole
April 27, 2017
Frameshift Mutation
April 12, 2017
Fungi
March 19, 2017
Gamete
April 12, 2017
Gametophyte
February 21, 2017
Gap Junction
April 14, 2017
Gardnerella Vaginalis
January 13, 2020
Gastrulation
January 25, 2017
Gene
May 21, 2019
Genetic Recombination
November 18, 2016
Genotype
December 4, 2016
Germ Theory
May 15, 2017
Gibberellin
May 20, 2018
Gland
June 24, 2017
Gluconeogenesis
May 7, 2017
Glycerol
June 23, 2017
Glycogen
June 9, 2017
Glycogenesis
April 17, 2019
Glycogenolysis
February 13, 2017
Golgi Apparatus
November 18, 2016
Gonad
November 12, 2016
Granulation Tissue
January 25, 2017
Haploid
January 7, 2018
Hematopoiesis
June 12, 2017
Heme
March 15, 2018
Heredity
December 21, 2016
Hermaphrodite
December 9, 2016
Heterochromatin
June 14, 2017
Heterozygous
December 6, 2016
Histology
January 23, 2018
Homeostasis
October 29, 2016
Homologous Chromosomes
November 8, 2016
Hormone
January 23, 2018
Hyaline Cartilage
January 20, 2017
Hydrolyze
November 18, 2016
Hydrophilic
December 17, 2016
Hydrophobic
December 15, 2016
Hydroxyl Group
April 5, 2017
Hyperosmotic
December 23, 2016
Hyperplasia
July 4, 2017
Hypertonic
December 29, 2016
Hypertonic Solution
January 20, 2017
Hyphae
January 21, 2018
Hypotonic
December 23, 2016
Hypotonic Solution
January 20, 2017
Independent Assortment
December 29, 2016
Integral Protein
August 25, 2018
Internal Respiration
February 12, 2017
Interphase
December 17, 2016
Interstitial Fluid
February 12, 2017
Intracellular Fluid
February 14, 2017
Intron
August 6, 2017
Isotonic
January 12, 2017
Isotonic Solution
February 9, 2017
Ketone Bodies
February 26, 2018
Krebs Cycle
January 12, 2017
Lac Operon
February 21, 2017
Lactase
February 28, 2017
Lactate Dehydrogenase
April 8, 2018
Lamina Propria
March 15, 2018
Law of Segregation
January 27, 2017
Leaf Cell
August 24, 2018
Ligand
April 22, 2018
Linked Genes
June 14, 2017
Lipid Bilayer
April 17, 2019
Lipolysis
September 17, 2018
Lymph
April 17, 2019
Lyse
November 14, 2016
Lysogenic Cycle
November 18, 2016
Lysosome
March 19, 2017
Lytic Cycle
October 7, 2018
Macromolecule
January 26, 2017
Meiosis
December 9, 2016
Mesoderm
June 13, 2017
Metaphase
December 21, 2016
Metaphase I
June 18, 2019
Metastasize
January 27, 2017
Microbiology
May 15, 2017
Microfilament
April 14, 2017
Microorganism
April 27, 2017
Microtubule
April 5, 2017
Missense Mutation
August 15, 2018
Mitochondria
March 3, 2017
Mitochondrion
September 7, 2017
Mitosis
December 9, 2016
Molecule
December 15, 2016
Monera
March 19, 2017
Monohybrid Cross
January 26, 2017
Monomer
February 13, 2017
Monosaccharide
January 11, 2017
Monosomy
March 3, 2017
Motility
March 3, 2017
mRNA
November 25, 2016
Mucous Membrane
January 31, 2017
Multicellular
November 22, 2016
Multiple Alleles
December 6, 2016
Muscle
December 8, 2017
Muscle Cell
December 8, 2017
Muscle Tissue
December 8, 2017
Mutation
April 5, 2017
Mycology
January 23, 2018
Myelin Sheath
February 10, 2017
Myofibril
May 18, 2017
NADP+
February 14, 2017
NADPH
February 14, 2017
Negative Feedback
July 30, 2017
Nephron
February 10, 2017
Nervous Tissue
February 28, 2017
Neurogenesis
May 14, 2017
Nitrogenous Base
October 7, 2018
NMDA Receptor
June 13, 2017
Nondisjunction
October 27, 2016
Nonsense Mutation
August 26, 2018
Notochord
March 15, 2018
Nuclear Membrane
October 27, 2016
Nucleic Acid
September 7, 2017
Nucleoid
December 23, 2016
Nucleotide
October 30, 2016
Obligate Anaerobes
October 7, 2018
Oncology
June 23, 2017
Operon
September 7, 2017
Organelle
January 20, 2017
Organism
December 6, 2016
Osmosis
November 1, 2016
Osmotic Pressure
March 20, 2017
Oxidative Phosphorylation
January 27, 2017
Oxidizing Agent
June 23, 2017
Parenchyma Cells
June 20, 2018
Passive Immunity
November 17, 2016
Passive Transport
October 27, 2016
Pathology
April 27, 2017
Peptide Bond
January 11, 2017
Peptide Hormones
August 21, 2018
Peptidoglycan
February 22, 2017
Peripheral Proteins
August 15, 2018
Peroxisome
April 5, 2017
Phagocytosis
April 5, 2017
Phenotype
November 28, 2016
Phloem
February 13, 2017
Phosphate Group
November 4, 2016
Phospholipid
November 8, 2016
Photosynthesis
July 30, 2017
Phototropism
March 13, 2017
Physiology
May 15, 2017
Phytoplankton
January 21, 2018
Pinocytosis
November 12, 2016
Plant Cell
April 5, 2017
Plant Hormones
August 21, 2018
Plant Tissue
August 25, 2018
Plasma Membrane
November 13, 2016
Plasmid
November 16, 2016
Plasmolysis
November 18, 2016
Point Mutation
November 22, 2016
Polar Molecule
February 27, 2017
Polysaccharide
January 20, 2017
Porphyrin
March 15, 2018
Positive Feedback
November 26, 2016
Prokaryote
December 15, 2016
Prokaryotic Cell
December 18, 2016
Prometaphase
December 17, 2016
Prophase
December 17, 2016
Prophase I
May 29, 2019
Prophase II
June 18, 2019
Proteolysis
August 6, 2017
Protist
October 29, 2016
Protoplasm
December 27, 2016
Protostome
April 5, 2017
Protozoa
January 13, 2017
Pseudopod
November 13, 2016
Pseudostratified Columnar Epithelium
January 6, 2017
Pyruvate
January 27, 2017
Receptor
February 27, 2018
Recessive Allele
December 4, 2016
Recombinant DNA
January 20, 2017
Ribosomal RNA
November 10, 2016
Ribosome
January 12, 2017
RNA Polymerase
November 10, 2016
Rough Endoplasmic Reticulum
January 31, 2017
Sarcolemma
March 1, 2017
Sarcomere
June 24, 2017
Scientific Method
March 3, 2017
Seashell
June 5, 2017
Secretion
June 2, 2017
Selective Permeability
November 12, 2016
Semipermeable Membrane
February 14, 2017
Serous Membrane
July 4, 2017
Serratia Marcescens
March 16, 2020
Sex Chromosomes
November 16, 2016
Sex Linked Genes
June 24, 2017
Sexual Reproduction
November 12, 2016
Signal Transduction
March 12, 2018
Silent Mutation
June 20, 2018
Simple Columnar Epithelium
January 14, 2017
Simple Cuboidal Epithelium
January 12, 2017
Simple Diffusion
February 10, 2017
Simple Squamous Epithelium
December 27, 2016
Sister Chromatids
November 17, 2016
Skeletal Muscle
December 8, 2017
Smooth Endoplasmic Reticulum
January 31, 2017
Smooth Muscle
December 8, 2017
Solute
December 13, 2016
Solution
December 13, 2016
Solvent
December 13, 2016
Somatic Cells
January 4, 2017
Spindle Fibers
September 17, 2018
Spirochete
April 14, 2017
Sporangium
May 18, 2017
Start Codon
March 19, 2017
Stratified Cuboidal Epithelium
October 25, 2018
Stratified Squamous Epithelium
January 3, 2017
Stroma
November 18, 2016
Submandibular Gland
November 20, 2019
Substitution Mutation
June 20, 2018
Substrate
December 4, 2016
Suprachiasmatic Nucleus
March 15, 2018
Synapsis
February 9, 2017
Telomerase
July 25, 2017
Telophase
December 21, 2016
Tertiary Structure
April 12, 2017
Test Cross
August 25, 2018
Thymine
March 12, 2017
Tight Junctions
April 14, 2017
Tissue
December 4, 2016
Tonicity
February 10, 2017
Transcription
November 22, 2016
Transcription Factor
May 17, 2017
Transferrin
September 17, 2018
Transitional Epithelium
January 12, 2017
Translation
November 23, 2016
Transpiration
January 31, 2017
Transport Protein
April 27, 2017
Trisomy 21 (Down Syndrome)
January 20, 2017
tRNA
November 29, 2016
Tropism
February 9, 2017
Turgid
January 11, 2017
Turgor Pressure
February 10, 2017
Unicellular
November 22, 2016
Vacuole
December 17, 2016
Vascular Tissue
May 20, 2018
Vasodilation
January 10, 2017
Vesicle
December 4, 2016
Virus
August 25, 2018
Water Potential
March 19, 2017
Xylem
November 28, 2016
Zygote
December 6, 2016
