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Biology Dictionary: R

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

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Dictionary > R
AllC

R

  • R factor
  • R loop
  • R plasmid
  • Ra
  • Rac
  • Race
  • Racemose
  • Rachis
  • Rachischisis
  • Rachischisis partialis
  • Rack
  • Rad
  • Radial
  • Radial immunodiffusion
  • Radial symmetry
  • Radiant
  • Radiata
  • Radiate
  • Radiates
  • Radiation
  • Radiation biophysics
  • Radiator
  • Radical
  • Radicle
  • Radiculoneuropathy
  • Radii
  • Radioactive
  • Radioactive atom
  • Radioactive decay
  • Radioactivity
  • Radiodensity
  • Radius
  • Radix ventralis
  • Radula
  • Raffinose
  • Raft
  • Rag
  • Ragged
  • Ragpickers disease
  • Ragsorters disease
  • Raillietina
  • Railroad nystagmus
  • Rain
  • Rainbow
  • Raineys corpuscles
  • Rainfall
  • Rainforest
  • Raisin
  • Raisins
  • Rake
  • Ram
  • Ramenta
  • Rami
  • Ramification
  • Ramp
  • Rampe
  • Rana
  • Ranal
  • Random allocation
  • Random Mating
  • Random sample
  • Range
  • Rank
  • Raphe
  • Rare
  • Rare species
  • Ras
  • Rascaless
  • Rasp
  • Ratchet
  • Rate
  • Ratify
  • Ratio
  • Rational
  • Rational drug design
  • Rationalization
  • Rations
  • Raw
  • Ray
  • Rayleigh criterion
  • Razor
  • Rb
  • Rda
  • RDNA
  • Reabsorption
  • React
  • Reactant
  • Reactants
  • Reaction
  • Reaction center
  • Reaction centre
  • Reaction of degeneration
  • Reactive oxygen species
  • Reactivity
  • Read
  • Reading frame
  • Reagent
  • Reaginic antibody
  • Real
  • Realized niche
  • Reannealing
  • Rear
  • Reason
  • Rebel
  • Rebound
  • Rebound phenomenon
  • Rebuck skin window technique
  • Recalcitrant
  • Recall
  • Recapitulation theory
  • Receiver
  • Receiver cell
  • Recent single-origin hypothesis
  • Receptacle
  • Receptaculum chyli
  • Reception
  • Receptive
  • Receptor protein
  • Receptor site
  • Recess
  • Recession
  • Recessive
  • Recessive Character
  • Recessive trait
  • Recipient
  • Reciprocal
  • Reciprocation
  • Reclamation
  • Recognition sequence
  • Recoil
  • Recoil atom
  • Recombinant
  • Recombinant DNA
  • Recombination
  • recombination DNA repair
  • Recombination nodule
  • Recon
  • Reconciliation Behavior
  • Reconstitution
  • Reconstruction
  • Record of decision
  • Recourse
  • Recover
  • Recovery
  • Recreation
  • Recruit
  • Recruitment
  • Rectangles
  • Rectification
  • Rectify
  • Rector
  • Rectouterine pouch
  • Rectovesical septum
  • Rectum
  • Recumbent
  • Recycling
  • Red algae
  • Red blood cell
  • Red drop effect
  • Redd
  • Redia
  • Redox reaction
  • Reduce
  • Reduced enamel epithelium
  • Reduced penetrance
  • Reducer
  • Reducing
  • Reducing agent
  • Reducing enzyme
  • Reducing sugar
  • Reductant
  • Reductase
  • Reduction
  • Reduction Division
  • Reduction en masse
  • Reductive Division
  • Redundancy
  • Redundancy Hypothesis
  • Redundant
  • Rees-ecker fluid
  • Reference method
  • References
  • Referral
  • Refine
  • Reflect
  • Reflected light
  • Reflected ray
  • Reflection
  • Reflectors
  • Reflex
  • Reflex arc
  • Reformation
  • Refract
  • Refractile
  • Refraction
  • Refractive index
  • Refractory
  • Refractory Period
  • Refrigeration
  • Refuse disposal
  • Refute
  • Regard
  • Regelation
  • Regeneration
  • Regime
  • Regimen
  • Regio inguinalis
  • Regio lumbalis
  • Regio mentalis
  • Regio zygomatica
  • Region
  • Regional anatomy
  • Regional continuity model
  • Regions
  • Register
  • Regma
  • Regression
  • Regression of the mean
  • Regular
  • Regulation
  • Regulator
  • Regulatory gene
  • Regulatory site
  • Regurgitation
  • Rehabilitation
  • Reids base line
  • Reign
  • Reinforcement
  • Reins
  • Relationship
  • Relative
  • Relative fitness
  • Relative value scales
  • Relative viscosity
  • Relax
  • Relaxation
  • Relaxed dna
  • Relaxed plasmid
  • Relay
  • Relay neuron
  • Release
  • Release phenomenon
  • Releases
  • Relevant
  • Reliability
  • Reliability coefficient
  • Relief
  • Relief area
  • Remainder
  • Remedies
  • Remission
  • Remit
  • Remittent fever
  • Remnant
  • Remnants
  • Remodeling
  • Remote
  • Remove
  • Renal calyses
  • Renal calyx
  • Renal column
  • Renal cortex
  • Renal medulla
  • Renal pelvis
  • Renal pyramid
  • Renal vein
  • Renewable resource
  • Rennase
  • Rennin
  • Renogastric
  • Repair
  • Repeated sequences
  • Repel
  • Repellent
  • Repent
  • Repetition
  • Repetitive DNA
  • Replacement
  • Replacement bone
  • Replacement model
  • Replenish
  • Repletion
  • Replica
  • Replica plating
  • Replicase
  • Replicate
  • Replication
  • Replication fork
  • Replication origin
  • Replicative form
  • Repolarization
  • Repolarize
  • Represent
  • Representative
  • Representatives
  • Repressible enzyme
  • Repression
  • Repression-sensitization
  • Repressor
  • Repressor protein
  • Reproduction
  • Reproductive adaptation
  • Reproductive bud
  • Reproductive Cell
  • Reproductive isolation
  • Reproductive system
  • Reptiles
  • Reptilia
  • Repulsion
  • RER
  • RES
  • Rescue
  • Research design
  • Research personnel
  • Research support
  • Resection
  • Reservation
  • Reserve
  • Reserves
  • Reservoir
  • Reservoir host
  • Resident
  • Resident fish
  • Residual
  • Residual air
  • Residual volume
  • Residue
  • Residuum
  • Resilience
  • Resin
  • Resistance
  • Resistance factor
  • Resistors
  • Resolution
  • Resolution acuity
  • Resolvase
  • Resolve
  • Resolving power
  • Resonance
  • Resonance energy transfer
  • Resorption
  • Resorption lacunae
  • Resource
  • Resources
  • Respect
  • Respiration
  • Respiration rate
  • Respiratory chain
  • Respiratory metabolism
  • Respiratory substrate
  • Respiratory system
  • Respire
  • Respirometer
  • Respond
  • Respondent conditioning
  • Response
  • Response hierarchy
  • Rest
  • Rest bite
  • Rest nitrogen
  • Rest position
  • Resting cells
  • Resting potential
  • Resting tidal volume
  • Restoration
  • Restraints
  • Restriction
  • Restriction endonuclease
  • Restriction enzyme
  • Restriction fragments
  • Restriction point
  • Restriction site
  • Restrictions
  • Restrictive temperature
  • Rests of serres
  • Result
  • Resultant
  • Results
  • Resurrection
  • Resuscitation
  • Retard
  • Retardation
  • Retards
  • Rete testis
  • Retention
  • Retention cyst
  • Retention form
  • Reticul-
  • Reticular activating system
  • Reticular fiber
  • Reticular lamina
  • Reticulated
  • Reticuloendothelial cell
  • Reticuloendothelial system
  • Retina
  • Retinal
  • Retinol
  • Retort
  • Retract
  • Retraction
  • Retreat
  • Retrieval
  • Retrograde
  • Retrograde axonal transport
  • Retrospective
  • Retrotransposon
  • Retrovirus
  • Rev
  • Revelation
  • Reverberating circuit
  • Reversal
  • Reversal learning
  • Reverse
  • Reverse banding
  • Reverse passive agglutination
  • Reverse transcriptase
  • Reverse transcription
  • Reversible
  • Reversion
  • Revertant
  • Revision
  • Revolution
  • Rh factor
  • Rheotaxis
  • Rheotropism
  • Rhese projection
  • Rhinalgia
  • Rhinarium
  • Rhizobium leguminosarum
  • Rhizoids
  • Rhizome
  • Rhizophora
  • Rhizopoda
  • Rhodopsin
  • Rib
  • Ribbon
  • Ribes ganglion
  • Ribonuclease
  • Ribonucleic acid
  • Ribonucleoprotein
  • Ribonucleoside
  • Ribonucleotide
  • Ribose
  • Ribosomal DNA
  • Ribosomal ribonucleic acid
  • Ribozyme
  • Rice
  • Rice-water stool
  • Rich
  • Rid
  • Rider
  • Riders bone
  • Ridge
  • Ridges
  • Riffle
  • Right fibrous trigone
  • Right sagittal fissure
  • Rigidity
  • Rigor
  • Rim
  • Ring
  • Ring test
  • Rings
  • Riot
  • Riparian buffer
  • Ripe
  • Ripening
  • Ripple
  • Risk
  • Risk factor
  • Risk factors
  • Ritual
  • Ritualistic behaviour
  • River
  • Rivet Hypothesis
  • Rmp
  • Rmv
  • RNA polymerase
  • Rna splicing
  • RNA virus
  • RNA-dependent DNA polymerase
  • Roach clasp
  • Roan
  • Roast
  • Robison ester
  • Robust
  • Rochelle salt
  • Rochers sign
  • Rock
  • Rod
  • Rods
  • Roe
  • Rogue
  • Role
  • Roll sulfur
  • Roller
  • Rollers nucleus
  • Rolling
  • Rolling circle mechanism
  • Ronnes nasal step
  • Roof of mouth
  • Room temperature
  • Roost
  • Root
  • Root apex
  • Root cap
  • Root cutting
  • Root filaments
  • Root Hair
  • Root pressure
  • Root sprout
  • Root System
  • Root tip
  • Rooted
  • Ropes test
  • Rosacea
  • Rosales
  • Rose
  • Roser-nelaton line
  • Roses position
  • Rosette
  • Rosette formation
  • Rostral
  • Rostrum
  • Rostrum sphenoidale
  • Rotary joint
  • Rotate
  • Rotation
  • Rotatoria
  • Rotten
  • Rough endoplasmic reticulum
  • Rough line
  • Roughage
  • Rouleaux formation
  • Round
  • Round heart
  • Rovsings sign
  • Row
  • ROY G. BIV
  • Rub
  • Rubies
  • Rubisco
  • Rudiment
  • Rudimentary
  • Rudiments
  • Rue
  • Ruffle
  • Rule of nines
  • Rumen
  • Ruminant
  • Rumination
  • Rummel tourniquet
  • Run
  • Rung
  • Runner
  • Runt disease
  • Rupture
  • Ruptures
  • Rural
  • Rush
  • Rushes
  • Rushton bodies
  • Rust
  • Rut
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