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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
  • A Band
  • A chain
  • A granules
  • A layer
  • A posteriori
  • A priori
  • A-v
  • A1-acid glycoprotein
  • Abandon
  • Abbreviations
  • Abdomen
  • Abdominal cavity
  • Abdominal raphe
  • Abdominopelvic cavity
  • Abdominopelvic splanchnic nerves
  • Abduction
  • Aberrant
  • Aberrant regeneration
  • Aberration
  • Abhorrent
  • Abilities
  • Ability
  • Abiogenesis
  • Abiotic
  • Abiotic factor
  • Abiotic factors
  • Abiotic Fixation
  • Abiotic resource
  • Abiotic stress
  • Ablation
  • Ablutomania
  • Abnormal
  • Abnormality
  • Abo blood group
  • Abolish
  • Aboral
  • Abortion
  • Abortive transduction
  • Abp
  • Abrams heart reflex
  • Abrasion
  • Abrasive
  • Abscisic acid
  • Abscissa
  • Abscission
  • Absence
  • Absent
  • Absolute fitness
  • Absolute Refractory Period
  • Absolution
  • Absorbance
  • Absorbent
  • Absorption cell
  • Absorption chromatography
  • Absorption Spectrum
  • Absorptive cells of intestine
  • Abstinence
  • Abstract
  • Abstraction
  • Abundance
  • Abundant
  • Abuse
  • Abyss
  • Abyssal
  • Acanthion
  • Acaulescent
  • Accelerate
  • Acceleration
  • Acceleration phase
  • Accelerator nerves
  • Accelerin
  • Accent
  • Accentuation
  • Acceptor
  • Access
  • Accessible
  • Accession
  • Accessories
  • Accessory
  • Accessory Chromosome
  • Accessory fruit
  • Accessory organs
  • Accessory pancreatic duct
  • Accessory pigment
  • Accessory symptom
  • Accident
  • Accidental host
  • Acclimation
  • Acclimatization
  • Accole forms
  • Accommodation
  • Accommodation reflex
  • Accounting
  • Accretion
  • Accretions
  • Accumulation
  • Accumulator Register
  • Accuracy
  • Ace
  • Acellular
  • Acentric Chromosome
  • Acentric fragment
  • Acephala
  • Acetabulum
  • Acetaldehyde
  • Acetate
  • Acetic acid
  • Acetobacter
  • Acetyl
  • Acetyl Coenzyme A
  • Acetyl-coa
  • Acetylcholine
  • Achenes
  • Achilles reflex
  • Achlorhydria
  • Achromatic
  • Achromia parasitica
  • Achromotrichia
  • Achylia pancreatica
  • Acid
  • Acid dye
  • Acid indicator
  • Acid Precipitation
  • Acid Rain
  • Acidic
  • Acidity
  • Acidophile
  • Acidosis
  • Acinar cells
  • Acinetobacter guillouiae
  • Acinetobacter junii
  • Acinetobacter lwoffii
  • Acme
  • Acoelomate
  • Acorn
  • Acp
  • Acquired
  • Acquired sensitivity
  • Acquired trait
  • Acquisition
  • Acrid
  • Acroarthritis
  • Acrobrachycephaly
  • Acrocentric chromosome
  • Acroesthesia
  • Acromegaly
  • Acromicria
  • Acrosome
  • Actin
  • Actinopterygian
  • Actinozoa
  • Action
  • Action potential
  • Action Spectrum
  • Activation
  • Activation energy
  • Activator
  • Active
  • Active Absorption
  • Active acetate
  • Active agglutination
  • Active centre
  • Active dry yeast
  • Active immunity
  • Active Ingredient
  • Active methionine
  • Active principle
  • Active site
  • Active transport
  • Activity
  • Acts
  • Actual resource
  • Acuity
  • Acusection
  • Acute
  • Acute febrile illness
  • Acyanogenic
  • Ad
  • Adair-koshland-nemethy-filmer model
  • Adaptation
  • Adaptations
  • Adaptive
  • Adaptive behaviour
  • Adaptive evolution
  • Adaptive radiation
  • Adaptive trait
  • Adaptive zone
  • Adder
  • Addiction
  • Addisons clinical planes
  • Addition
  • Addition compound
  • Additions
  • Additive
  • Additive effect
  • Additive genes
  • Address
  • Adduction
  • Adductor muscle
  • Ade
  • Adenine
  • Adenine nucleotide
  • Adenofibrosis
  • Adenosine
  • Adenosine diphosphate
  • Adenosine monophosphate
  • Adenosine triphosphate
  • Adenylate
  • Adequate
  • Adequate stimulus
  • Adfluvial
  • Adherence
  • Adherent
  • Adhering junction
  • Adhesion
  • Adhesive
  • Adient behaviour
  • Adipectomy
  • Adipocyte
  • Adipose tissue
  • Aditus laryngis
  • Adjacent
  • Adjunct
  • Adjust
  • Adjustment
  • Adjutant
  • Adjuvant
  • Administer
  • Administration
  • Adnexa oculi
  • Adnexum
  • Adolescence
  • Adoption
  • Adrenaline
  • Adsorption
  • Adult
  • Adultery
  • Advance
  • Advent
  • Adventitious
  • Adventitious bud
  • Adventitious embryony
  • Adventitious root
  • Adverse effects
  • Advocate
  • Aerate
  • Aeration
  • Aerial
  • Aerial mycelium
  • Aerial Respiration
  • Aerial root
  • Aero-
  • Aerobe
  • Aerobic
  • Aerobic bacteria
  • Aerobic exercise
  • Aerobic organism
  • Aerobic process
  • Aerobic respiration
  • Aerosol
  • Aerotolerant
  • Aerotropism
  • Aestivation
  • Aetiolated
  • Aetiological
  • Aetiology
  • Af
  • Affect
  • Affected
  • Affection
  • Afferent
  • Afferent Nerve
  • Afferent neuron
  • Affinity
  • Affinity chromatography
  • Affirmation
  • Affix
  • Affluent
  • Afrotropical realm
  • Ag
  • Agar
  • Agar-agar
  • Agarose
  • Agave
  • Age distribution
  • Age groups
  • Age-class
  • Agent
  • Agents
  • Agglutination
  • Agglutinin
  • Agglutinogen
  • Aggravation
  • Aggregate fruit
  • Aggregated lymphatic follicles
  • Aggregated lymphatic nodules
  • Aggregation
  • Aggressin
  • Aggression
  • Agitation
  • Agnathan
  • Agonal rhythm
  • Agonal thrombus
  • Agonism
  • Agonist
  • Agonist muscle
  • Agony
  • Agranular endoplasmic reticulum
  • Agranular leukocyte
  • Agranulocyte
  • Agretope
  • Agriculture
  • Ahaustral
  • Ahf
  • Aid
  • Aids
  • Ail
  • Ailment
  • Air
  • Air bladder
  • Air cell
  • Air chamber
  • Air conduction
  • Air Pollution
  • Air pressure
  • Air sac
  • Air Space
  • Airway
  • Airy disk
  • Aitiology
  • Akin
  • Akinetes
  • Al
  • Ala
  • Ala minor
  • Ala orbitalis
  • Ala ossis ilii
  • Alanine
  • Alar chest
  • Alarmone
  • Alb
  • Alba
  • Albers-Schonberg disease
  • Albinism
  • Albino
  • Albumen
  • Albumin
  • Albuminoids
  • Albuminous
  • Albuminous cell
  • Alcohol
  • Alcoholic
  • Alcoholic beverages
  • Alcoholic Fermentation
  • Aldehyde
  • Aldohexoses
  • Aldose
  • Aldosterone
  • Aldotriose
  • Alethiology
  • Aleurone Layer
  • Alfilaria
  • Algae
  • Algal bloom
  • Algology
  • Algopsychalia
  • Algorithm
  • Alienation
  • Aliment
  • Alimentary canal
  • Alimentary glycosuria
  • Alimentary tract
  • Aliphatic
  • Aliphatic acids
  • Aliphatic compound
  • Aliquot
  • Alive
  • Alizarin
  • Alkadienes
  • Alkali
  • Alkaline
  • Alkaline reaction
  • Alkalinity
  • Alkaliphile
  • Alkaloid
  • Alkalosis
  • All-Or-None-Law
  • Allantois
  • Allee effect
  • Allele
  • Allele frequency
  • Allelic exclusion
  • Allelism
  • Allelopathy
  • Allergen
  • Allergy
  • Allies
  • Alligator
  • Alliteration
  • Allium
  • Allogamy
  • Allogeneic
  • Alloimmunity
  • Allometric Growth
  • Allomone
  • Allomorph
  • Allopatric speciation
  • Allopatry
  • Allopolyploidy
  • Allose
  • Allosteric
  • Allosteric Enzyme
  • Allosteric Inhibitors
  • Allotetraploid
  • Allotropy
  • Alloy
  • Allozyme
  • Alluvial Soil
  • Alpaca
  • Alpha hemolysis
  • Alpha-amino acids
  • Alpha-amylase
  • Alpha-helix
  • Alphaproteobacteria
  • Alpine
  • Alt
  • Alteration
  • Alternate
  • Alternative
  • Alternative hypothesis
  • Altitude
  • Alto
  • Altrose
  • Altruism
  • Alum-haematoxylin
  • Alveolalgia
  • Alveolar air
  • Alveolar cell
  • Alveolar duct
  • Alveolar gland
  • Alveolar osteitis
  • Alveolotomy
  • Alveolus
  • Amalgam
  • Amalgamate
  • Amalgamation
  • Amaroidal
  • Amastigote
  • Amaurotic pupil
  • Amber
  • Ambient
  • Ambiguity
  • Ambiguous
  • Ambiguous codon
  • Ambulacral
  • Amelanism
  • Amenable
  • Ametabolism
  • Ametaboly
  • Amharic
  • Ami
  • Amiable
  • Amidase
  • Amide
  • Amide linkages
  • Amination
  • Amine
  • Amino acid
  • Amino acid sequence
  • Amino group
  • Amino sugar
  • Amitosis
  • Ammonia
  • Ammonia assimilation
  • Ammonification
  • Ammonite
  • Ammonium
  • Ammonotelism
  • Ammotherapy
  • Amnion
  • Amniote
  • Amniotic Cavity
  • Amniotic fluid
  • Amniotic sac
  • Amoeba
  • Amoebic dysentery
  • Amoebocyte
  • Amoeboid
  • Amoeboid movement
  • Amorph
  • Amorphia
  • Amorphic mutation
  • Amorphous
  • Amount
  • Amphiaster
  • Amphibia
  • Amphibian
  • Amphibious
  • Amphimixis
  • Amphipathic
  • Amphiphile
  • Amphoteric
  • Amphotonia
  • Ampicillin resistance
  • Ample
  • Amplification
  • Amplifier
  • Amplifier host
  • Amplify
  • Amplitude
  • Ampulla
  • Amsterdam syndrome
  • Amu
  • Amyl
  • Amyl valerate
  • Amyloglucosidase
  • Amyloplast
  • Amylopsin
  • Amylose
  • Anabiosis
  • Anabolic pathway
  • Anabolic steroid
  • Anabolism
  • Anadromous
  • Anadromous fish
  • Anaemia
  • Anaerobe
  • Anaerobic
  • Anaerobic bacteria
  • Anaerobic exercise
  • Anaerobic process
  • Anaerobic respiration
  • Anaesthesia
  • Anaesthetic
  • Anagenesis
  • Anal
  • Anal orifice
  • Anal pit
  • Anal pore
  • Analgesic
  • Analog
  • Analogous
  • Analogous structures
  • Analogue
  • Analogy
  • Analysis
  • Analyte
  • Analytical
  • Analyze
  • Anamniote
  • Anaphase I
  • Anaphase II
  • Anaphylactic shock
  • Anaplasia
  • Anarthropoda
  • Anas
  • Anastomoses
  • Anastomosis
  • Anathema
  • Anatomical
  • Anatomical plane
  • Anatomy
  • Ancestors
  • Ancestral
  • Ancestry
  • Anchor
  • Anchor splint
  • Anchorage
  • Anchorage independence
  • Anchorage-independent cell
  • Anchoring junction
  • Anchors
  • Ancillary
  • Ancylostoma
  • Ancylostoma duodenale
  • Ancylostomiasis
  • Andro-
  • Androecium
  • Androgen
  • Androsterone
  • Anemia
  • Aneuploidy
  • Anger
  • Angiosperm
  • Angiostenosis
  • Angiotensinogen
  • Angiotomy
  • Angle
  • Angle of mouth
  • Angular
  • Angular aperture
  • Angulation
  • Angulus sphenoidalis ossis parietalis
  • Anhidrosis
  • Animal
  • Animal cell culture
  • Animal Kingdom
  • Animal pole
  • Animal protein factor
  • Animal testing
  • Animalia
  • Animals
  • Animals suckling
  • Animate
  • Anion
  • Anisogamy
  • Anisotropic
  • Anneal
  • Annealing
  • Annelida
  • Annotated Diagram
  • Annual
  • Annual Ring
  • Annular band
  • Annular cartilage
  • Annular lipid
  • Annular Thickening
  • Annulospiral ending
  • Anodal opening contraction
  • Anode rays
  • Anoderm
  • Anomalies
  • Anomalous
  • Anomalous trichromatism
  • Anomaly
  • Anomer
  • Anomeric carbon
  • Anoxia
  • Anoxic
  • Anoxygenic
  • Answer
  • Ant
  • Ant thrushes
  • Antagonism
  • Antagonist
  • Antagonistic effect
  • Antagonistic Muscle
  • Antarctic realm
  • Ante cibum
  • Antebrachium
  • Antecardium
  • Antecedent
  • Antecubital fossa
  • Antecubital space
  • Antelope
  • Antemortem thrombus
  • Antenna
  • Antennapedia
  • Anterior
  • Anterior crural nerve
  • Anterior extremity
  • Anterior funiculus
  • Anterior nasal spine
  • Anterior part
  • Anterior pituitary
  • Anterior primary division
  • Anterior surface
  • Anterolateral
  • Anterolateral central arteries
  • Anterolateral fontanel
  • Anterolateral system
  • Anthema
  • Anther
  • Anther cap
  • Anther culture
  • Antheridium
  • Anthology
  • Anthophore
  • Anthozoan
  • Anthracite
  • Anthracosis
  • Anthropogenic
  • Anthropography
  • Anthropoids
  • Anthroponosis
  • Anthropophilia
  • Anthropophilic
  • Antibacterial
  • Antibiotic
  • Antibody
  • Antibody diversity
  • Antibody-forming cell
  • Anticoagulant
  • Anticodon
  • Antifungal
  • Antifungicide
  • Antigen
  • Antigen-antibody complex
  • Antigenic
  • Antigenic variation
  • Antigenicity
  • Antihistamines
  • Antimicrobial
  • Antimorphic mutation
  • Antioxidants
  • Antiport
  • Antisense strand
  • Antisepalous
  • Antiseptic
  • Antiserum
  • Antitoxin
  • Antiviral
  • Antivitamin
  • Antrum
  • Antrum of Highmore
  • Anucleate
  • Anus
  • Anvil
  • Aorta
  • Apara
  • Apathy
  • Ape
  • Apertura mediana ventriculi quarti
  • Apertura pelvis superior
  • Apertura thoracis superior
  • Aperture
  • Aperture function
  • Apetalous
  • Apex
  • Apex of head of fibula
  • Aphotic Zone
  • Apical
  • Apical bud
  • Apical complex
  • Apical Dominance
  • Apical Growth
  • Apical Meristem
  • Apical meristem
  • Apical plasma membrane
  • Apicomplexa
  • Apicomplexan
  • Aplanospore
  • Aplasia
  • Apocarpous gynoecium
  • Apocrine gland
  • Apodous
  • Apoenzyme
  • Apolar
  • Apomixis
  • Apomorphy
  • Aponeurorrhaphy
  • Aponeurosis
  • Apoplast
  • Apoplectic cyst
  • Apoptosis
  • Aporepressor
  • Apostate
  • Apothegm
  • Apparatus
  • Apparent
  • Apparent competition
  • Apparent viscosity
  • Apparition
  • Appeal
  • Appearance
  • Appendage
  • Appendages
  • Appendages of eye
  • Appendicular
  • Appendix
  • Appetitive behaviour
  • Apple
  • Apple jelly nodules
  • Apple oil
  • Application
  • Applications
  • Applied anatomy
  • Applied science
  • Apposition
  • Appositional growth
  • Approach-approach conflict
  • Approach-avoidance conflict
  • Approximation
  • Apractagnosia
  • Apragmatism
  • Apron
  • Aprophoria
  • Aps
  • Apt
  • Apt test
  • Apteria
  • Aquaporin
  • Aquarium
  • Aquatic
  • Aquatic locomotion
  • Aquatic plant
  • Aquatic plants
  • Aquatic Respiration
  • Aquatic root
  • Aqueduct
  • Aqueous
  • Aqueous humor
  • Aqueous solution
  • Ara
  • Arabinose
  • Arable Farming
  • Arachidonic acid
  • Arachnida
  • Arachnology
  • Arbor
  • Arboreal
  • Arboreal locomotion
  • Arch
  • Archaea
  • Archaean
  • Archaebacteria
  • Archaellum
  • Archaeocyte
  • Archaeopteryx
  • Archaeplastida
  • Archaic
  • Archamoebae
  • Archegonium
  • Archenteron
  • Archeocerebellum
  • Arches
  • Archetype
  • Architecture
  • Architeuthis
  • Arctic
  • Arcus venosus palmaris superficialis
  • Arcus vertebrae
  • Area
  • Areal cover
  • Arena
  • Areola
  • Areolar gland
  • Areolar tissue
  • Areole
  • Arg
  • Arginine
  • Argipressin
  • Argument
  • Arguments
  • Argyrophilic cell
  • Ariel gazelle
  • Aries
  • Arise
  • Aristotle
  • Arm
  • Armadillidiidae
  • Armature
  • Aroma
  • Aromatase
  • Aromatic compound
  • Arousal
  • Arrangement
  • Arrangements
  • Arrector pili muscles
  • Arrectores pilorum
  • Arrest
  • Arrested tuberculosis
  • Arrhenotoky
  • Arrow poison
  • Artefact
  • Arterial embolism
  • Arteriolar sclerosis
  • Arteriole
  • Arteriovenous shunt
  • Artery
  • Arthritis
  • Arthrolithiasis
  • Arthrology
  • Arthropod
  • Arthropodology
  • Article
  • Articular circumference of radius
  • Articular facet
  • Articular processes
  • Articular surface
  • Articulata
  • Articulate
  • Articulated skeleton
  • Articulatio complexa
  • Articulatio composita
  • Articulatio radiocarpea
  • Articulatio tarsi transversa
  • Articulatio trochoidea
  • Articulation
  • Articulationes membri superioris liberi
  • Artifact
  • Artifactual
  • Artificial
  • Artificial active immunity
  • Artificial passive immunity
  • Artificial respiration
  • Artificial Selection
  • Artificially acquired active immunity
  • Artificially acquired passive immunity
  • Artiodactyla
  • Asbestos
  • Ascaricide
  • Ascaris
  • Ascaris lumbricoides
  • Ascendant
  • Ascending
  • Ascending process
  • Ascension
  • Ascetic
  • Ascidians
  • Ascomycetes
  • Ascospore
  • Aseptic
  • Asexual
  • Ash
  • Asialoglycoprotein
  • Asian Glossy Starling
  • Asn
  • Asp
  • Asparagine
  • Asparagus
  • Aspartame
  • Aspartate
  • Aspect
  • Aspect ratio
  • Aspergillus
  • Aspermia
  • Aspidium
  • Aspirate
  • Aspiration
  • Aspire
  • Ass
  • Assam fever
  • Assay
  • Assert
  • Assessment
  • Assimilate
  • Assimilation
  • Assimilation pelvis
  • Assist
  • Associate
  • Associates
  • Association
  • Association constant
  • Association fibres
  • Assortative mating
  • Assortment
  • Assumption
  • Assumptions
  • Ast
  • Asteatosis
  • Aster
  • Asteraceae
  • Asteroid
  • Asteroids
  • Asthenic personality
  • Asthenic personality disorder
  • Astomia
  • Astragalus
  • Astral microtubule
  • Astrosphere
  • Asymmetry
  • Asymptomatic
  • Atavism
  • Athlete
  • Atl
  • Atmolysis
  • Atmolyzation
  • Atmos
  • Atmosphere
  • Atmospheric
  • Atmospheric pressure
  • Atmospherization
  • Atom
  • Atomic mass
  • Atomic number
  • Atomic theory
  • Atomic weight
  • Atomism
  • Atomy
  • Atopognosia
  • ATP
  • ATP synthase
  • ATPase
  • Atria
  • Atrial natriuretic hormone
  • Atrial syncytium
  • Atrial systole
  • Atriotomy
  • Atrioventricular sulcus
  • Atrioventricular valve
  • Atrium
  • Atrophy
  • Att site
  • Attachment
  • Attachment sites
  • Attenuated
  • Attenuation factor
  • Attract
  • Attractant
  • Attraction
  • Attrition
  • Atypical
  • Au
  • Audit
  • Audition
  • Auditory
  • Auger
  • Augmentation
  • Aureole
  • Auricle
  • Auricula
  • Auricular standstill
  • Austin disease
  • Australasia realm
  • Autecology
  • Authority figure
  • Autism
  • Auto-
  • Autoactivation
  • Autoantigen
  • Autochthonous
  • Autocrine
  • Autogenous
  • Autograph
  • Autoimmune disease
  • Autoimmunity
  • Autolysis
  • Automatic
  • Automation
  • Automixis
  • Autonomic
  • Autonomic nervous system
  • Autonomous
  • Autophagy
  • Autophosphorylation
  • Autophytic Plant
  • Autopolyploidy
  • Autopsy
  • Autosomal
  • Autosomal Inheritance
  • Autosome
  • Autospore
  • Autotomy
  • Autotroph
  • Autotrophy
  • Autotype
  • Auxanographic method
  • Auxanology
  • Auxetic growth
  • Auxiliary
  • Auxin
  • Auxochrome
  • Auxotrophic mutant
  • Auxotyping
  • Avascular
  • Avenue
  • Average
  • Aves
  • Avian
  • Avicennia germinans
  • Avicula
  • Avidity
  • Avocation
  • Avoidance Behaviour
  • Avoidance conditioning
  • Avoidance training
  • Avoidance-avoidance conflict
  • Ax
  • Axenic culture
  • Axes
  • Axial
  • Axial ametropia
  • Axial angle
  • Axial projection
  • Axillary
  • Axillary bud
  • Axils
  • Axis
  • Axon
  • Axon hillock
  • Axon terminal
  • Axoneme
  • Axonogenesis
  • Azoospermia
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