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