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Biology Dictionary: A

Search or browse the dictionary for the definition of biology terms starting with the letter “A”.

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Dictionary > A
AllA

A

  • A Band
  • A chain
  • A layer
  • A posteriori
  • A-v
  • Abdomen
  • Abdominal cavity
  • Abdominal raphe
  • Abdominal reflex
  • Abdominopelvic cavity
  • Abduction
  • Aberrant regeneration
  • Ability
  • Abiogenesis
  • Abiotic
  • Abiotic factor
  • Abiotic Fixation
  • Abiotic resource
  • Abiotic stress
  • Abnormal
  • Abo blood group
  • Abortion
  • Abortive transduction
  • Abscisic acid
  • Abscissa
  • Abscission
  • Absolute fitness
  • Absolute Refractory Period
  • Absorbance
  • Absorption
  • Absorption cell
  • Absorption chromatography
  • Absorption Spectrum
  • Absorptive cells of intestine
  • Abtropfung
  • Abundance
  • Acceptor
  • Accessories
  • Accessory Chromosome
  • Accessory fruit
  • Accessory organs
  • Accessory pigment
  • Accidental host
  • Acclimation
  • Accole forms
  • Accommodation
  • Accommodation of nerve
  • Accommodation reflex
  • Accretions
  • Accumulation
  • Acellular
  • Acetabulum
  • Acetobacter
  • Acetyl Coenzyme A
  • Acetylcholine
  • Achenes
  • Achilles reflex
  • Achlorhydria
  • Achromatic
  • Achromia parasitica
  • Achromotrichia
  • Acid
  • Acid dye
  • Acid indicator
  • Acid Precipitation
  • Acidic
  • Acidophile
  • Acidosis
  • Acinetobacter lwoffii
  • Acoelomate
  • Acorn
  • Acquired
  • Acquired sensitivity
  • Acquired trait
  • Acroarthritis
  • Acrobrachycephaly
  • Acrocentric chromosome
  • Acromegaly
  • Actinopterygian
  • Actinozoa
  • Action potential
  • Activation
  • Activation energy
  • Activator
  • Active agglutination
  • Active centre
  • Active dry yeast
  • Active principle
  • Active site
  • Active transport
  • Activity
  • Actual resource
  • Acute febrile illness
  • Adair-koshland-nemethy-filmer model
  • Adansonian classification
  • Adaptation
  • Adaptive behaviour
  • Adaptive evolution
  • Adaptive radiation
  • Adaptive trait
  • Adaptive zone
  • Adder
  • Addition
  • Additive effect
  • Additive genes
  • Adduction
  • Adductor muscle
  • Adenine
  • Adenine nucleotide
  • Adenofibrosis
  • Adenosine
  • Adenosine diphosphate
  • Adenosine monophosphate
  • Adenosine triphosphate
  • Adfluvial
  • Adhering junction
  • Adhesion
  • Adipocyte
  • Adipose tissue
  • Adjuvant
  • Administration
  • Adrenaline
  • Adsorption
  • Adultery
  • Adventitious bud
  • Adventitious embryony
  • Adventitious root
  • Adverse effects
  • Aeration
  • Aerial
  • Aerial mycelium
  • Aerial Respiration
  • Aerial root
  • Aerobe
  • Aerobic
  • Aerobic bacteria
  • Aerobic process
  • Aerobic respiration
  • Aerosol
  • Aerotolerant
  • Aerotropism
  • Aestivation
  • Aetiolated
  • Aetiology
  • Af
  • Afferent Nerve
  • Afferent neuron
  • Affinity
  • Affinity chromatography
  • Afrotropical realm
  • Agar
  • Agarose
  • Age distribution
  • Age groups
  • Agent
  • Agglutination
  • Agglutinin
  • Agglutinogen
  • Agglutinophilic
  • Aggregate
  • Aggregate fruit
  • Aggregated lymphatic follicles
  • Aggregated lymphatic nodules
  • Aggressin
  • Aggression
  • Agitation
  • Agnathan
  • Agonal rhythm
  • Agonist
  • Agonist muscle
  • Agony
  • Agretope
  • Agriculture
  • Ailment
  • Air
  • Air bladder
  • Air cell
  • Air conduction
  • Air Pollution
  • Air pressure
  • Airway
  • Airy disk
  • Akinetes
  • Ala minor
  • Ala orbitalis
  • Alanine
  • Albinism
  • Albino
  • Albumin
  • Alcohol
  • Alcoholic Fermentation
  • Aldohexoses
  • Aldose
  • Aldosterone
  • Aldotriose
  • Algae
  • Algal bloom
  • Algology
  • Aliment
  • Alimentary canal
  • Alimentary glycosuria
  • Aliphatic
  • Aliphatic acids
  • Aliquot
  • Alive
  • Alkadienes
  • Alkaline
  • Alkaline reaction
  • Alkaliphile
  • All-Or-None-Law
  • Allantois
  • Allee effect
  • Allele
  • Allele frequency
  • Allelic exclusion
  • Allelism
  • Allergy
  • Alligator
  • Allogamy
  • Alloimmunity
  • Allometric Growth
  • Allopatric speciation
  • Allopatry
  • Allopolyploidy
  • Allose
  • Allosteric Inhibitors
  • Allotetraploid
  • Alpaca
  • Alpha-helix
  • Alphaproteobacteria
  • Alt
  • Alternative hypothesis
  • Altitude
  • Altrose
  • Alveolalgia
  • Alveolar cell
  • Alveolar duct
  • Alveolar gland
  • Alveolus
  • Amastigote
  • Amaurotic pupil
  • Ambient
  • Ambiguous codon
  • Amelanism
  • Ametaboly
  • Ami
  • Amino acid
  • Amino acid sequence
  • Amino sugar
  • Amitosis
  • Ammonia
  • Ammonification
  • Ammonotelism
  • Amnion
  • Amniote
  • Amniotic Cavity
  • Amniotic fluid
  • Amniotic sac
  • Amoeba
  • Amoebic dysentery
  • Amoebocyte
  • Amoeboid
  • Amoeboid movement
  • Amoebozoa
  • Amorphic mutation
  • Amorphous
  • Amphimixis
  • Amphipathic
  • Amphoteric
  • Amplification
  • Amplifier host
  • Amplitude
  • Amylase
  • Amyloglucosidase
  • Amylopectin
  • Amyloplast
  • Amylose
  • Anabolic pathway
  • Anabolic steroid
  • Anabolism
  • Anaerobe
  • Anaerobic
  • Anaerobic bacteria
  • Anaerobic exercise
  • Anaerobic process
  • Anaerobic respiration
  • Anaesthetic
  • Analgesic
  • Analog
  • Analogous
  • Analogous structures
  • Analogy
  • Anamniote
  • Anaphase
  • Anaphase I
  • Anaphase II
  • Anaphylactic shock
  • Anarthropoda
  • Anastomoses
  • Anastomosis
  • Anatomical
  • Anatomical plane
  • Anatomy
  • Ancestors
  • Anchor
  • Anchorage
  • Anchorage independence
  • Anchorage-independent cell
  • Anchoring junction
  • Ancylostoma
  • Ancylostoma duodenale
  • Androecium
  • Androsterone
  • Anemia
  • Aneuploidy
  • Angiosperm
  • Angiostenosis
  • Angiotensinogen
  • Angiotomy
  • Angulation
  • Angulus sphenoidalis ossis parietalis
  • Anhidrosis
  • Animal
  • Animal cell
  • Animal cell culture
  • Animal Kingdom
  • Animal testing
  • Animals
  • Annealing
  • Annelida
  • Annotated Diagram
  • Annular band
  • Annular lipid
  • Anodal opening contraction
  • Anoderm
  • Anomaly
  • Anomer
  • Anomeric carbon
  • Anoxia
  • Ant
  • Antagonism
  • Antagonist
  • Antagonistic effect
  • Antagonistic Muscle
  • Antarctic realm
  • Antebrachium
  • Antecardium
  • Antecubital fossa
  • Antecubital space
  • Antelope
  • Antemortem thrombus
  • Antenna
  • Antennapedia
  • Anterior
  • Anterior extremity
  • Anterior funiculus
  • Anterior primary division
  • Anterolateral
  • Anterolateral system
  • Anther
  • Anther culture
  • Anthozoan
  • Anthropography
  • Anthropoids
  • Anthroponosis
  • Anthropophilia
  • Anthropophilic
  • Antibacterial
  • Antibiotic
  • Antibody
  • Antibody diversity
  • Antibody-forming cell
  • Anticipatory control
  • Anticoagulant
  • Anticodon
  • Antifungal
  • Antifungicide
  • Antigen
  • Antigen-antibody complex
  • Antigenic variation
  • Antigenicity
  • Antimorphic mutation
  • Antioxidants
  • Antisepalous
  • Antiserum
  • Antitoxin
  • Antivitamin
  • Anus
  • Ape
  • Ape hand
  • Apertura mediana ventriculi quarti
  • Apertura thoracis superior
  • Aperture
  • Apetalous
  • Apex
  • Apex of head of fibula
  • Apical bud
  • Apical complex
  • Apical Dominance
  • Apical Meristem
  • Apical meristem
  • Apicomplexa
  • Aplanospore
  • Aplasia
  • Apocarpous gynoecium
  • Apocrine gland
  • Apoenzyme
  • Apolar
  • Apomixis
  • Apomorphy
  • Aponeurorrhaphy
  • Apoplast
  • Apoptosis
  • Apparatus
  • Apparent competition
  • Appearance
  • Appendage
  • Appendages
  • Appendages of eye
  • Appendix
  • Apple
  • Application
  • Applied science
  • Appositional growth
  • Approach-approach conflict
  • Approach-avoidance conflict
  • Apractagnosia
  • Apteria
  • Aquatic
  • Aquatic Respiration
  • Aquatic root
  • Aqueous humor
  • Aqueous solution
  • Arachnology
  • Arboreal
  • Arboreal locomotion
  • Archaea
  • Archaean
  • Archaebacteria
  • Archaellum
  • Archaeplastida
  • Archamoebae
  • Archeocerebellum
  • Archetype
  • Arcus venosus palmaris superficialis
  • Arcus vertebrae
  • Area
  • Areal cover
  • Areola
  • Areolar gland
  • Areolar tissue
  • Areole
  • Argipressin
  • Aristotle
  • Arm
  • Armadillidiidae
  • Aroma
  • Arrector pili muscles
  • Arrectores pilorum
  • Arrest
  • Arrested tuberculosis
  • Arrhenotoky
  • Arrow poison
  • Artefact
  • Arteriolar sclerosis
  • Arteriole
  • Arthritis
  • Arthrology
  • Arthropod
  • Arthropodology
  • Article
  • Articular surface
  • Articulata
  • Articulate
  • Articulatio radiocarpea
  • Articulatio tarsi transversa
  • Articulatio trochoidea
  • Articulation
  • Articulationes membri superioris liberi
  • Artificial active immunity
  • Artificial passive immunity
  • Ascaris
  • Ascaris lumbricoides
  • Ascendant
  • Ascidians
  • Asexual reproduction
  • Asian Glossy Starling
  • Asp
  • Asparagus
  • Aspartame
  • Aspartate
  • Aspergillus
  • Aspermia
  • Aspidium
  • Aspirate
  • Ass
  • Assay
  • Assimilation
  • Association
  • Association constant
  • Assumption
  • Asteatosis
  • Aster
  • Asteraceae
  • Asthenic personality disorder
  • Astomia
  • Astragalus
  • Asymmetry
  • Asymptomatic
  • Atavism
  • Atmospherization
  • Atom
  • Atomic mass
  • Atomic weight
  • ATP synthase
  • Atria
  • Atrial natriuretic hormone
  • Atrial syncytium
  • Atriotomy
  • Atrioventricular sulcus
  • Atrioventricular valve
  • Atrium
  • Atrophy
  • Attraction
  • Austin disease
  • Australasia realm
  • Autecology
  • Authority figure
  • Autoantigen
  • Autocrine signaling
  • Autogenous
  • Autoimmune disease
  • Autoimmunity
  • Automixis
  • Autonomous
  • Autophagy
  • Autophosphorylation
  • Autophytic Plant
  • Autopolyploidy
  • Autosome
  • Autotomy
  • Autotroph
  • Auxanographic method
  • Auxetic growth
  • Auxin
  • Auxotyping
  • Avascular
  • Average
  • Aves
  • Avidity
  • Avoidance conditioning
  • Avoidance-avoidance conflict
  • Axenic culture
  • Axial ametropia
  • Axial projection
  • Axils
  • Axis
  • Axon
  • Axon hillock
  • Axon terminal
  • Axoneme
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