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Biology Dictionary: P

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

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Dictionary > P
AllC

-

  • -plasia

P

  • P face
  • P1
  • P680
  • Pace
  • Pacemaker
  • Pachynema
  • Pachytene
  • Pacinian corpuscles
  • Packaging
  • Packed cell volume
  • Pain
  • Pair
  • Pair-rule gene
  • Palaearctic realm
  • Palaeobotany
  • Paleoneurology
  • Paleozoic
  • Palm
  • Palma manus
  • Palmar crease
  • Palmar surface
  • Palmate
  • Palmitic acid
  • Palmitin
  • Palp
  • Pancreas
  • Pancreatic juice
  • Pancreatic lipase
  • Pandemic
  • Pangenesis
  • Pant
  • Pantherinae
  • Paper chromatography
  • Papilionaceous
  • Papilla incisiva
  • Papillary dermis
  • Papovaviridae
  • Papyraceous scars
  • Paracentric inversion
  • Paracrine
  • Paracrine signaling
  • Paracystitis
  • Paradenitis
  • Parallax
  • Parallel evolution
  • Paralogy
  • Parameter
  • Paramorphism
  • Paramural body
  • Parapatric speciation
  • Paraphyletic
  • Parasagittal
  • Parasagittal plane
  • Parasegment
  • Parasite
  • Parasitism
  • Parasitoid
  • Parasitoidism
  • Parasitology
  • Parasymbiosis
  • Parasympathetic nervous system
  • Paratenic host
  • Parazoa
  • Parchment skin
  • Parenchyma
  • Parent
  • Parent cell
  • Parental generation
  • Parenteral
  • Parenthesome
  • Parietal cell
  • Parietes
  • Paroxysmal cerebral dysrhythmia
  • Pars basilaris ossis occipitalis
  • Parthenogenesis
  • Partial pressure
  • Partially-permeable membrane
  • Particle
  • Particulate inheritance
  • Parvorder
  • Paschen bodies
  • Passive agglutination
  • Passive immunity
  • Passive transport
  • Passive vasodilation
  • Past-pointing
  • Pasteur effect
  • Patau syndrome
  • Patella
  • Patellar reflex
  • Patent
  • Paternity
  • Pathogen
  • Pathogenicity
  • Pathologic
  • Pathophysiology
  • Pathotoxin
  • Pattern formation
  • Pawn
  • PBI test
  • Pea
  • Peach
  • Peak plasma drug concentration
  • Peanut
  • Pearl
  • Pectinase
  • Pedal
  • Pedicel
  • Pedicle
  • Pedigree
  • Pedigree analysis
  • Pedipalp
  • Pedunculated
  • Peg-and-socket joint
  • Pellets
  • Pelvic axis
  • Pelvic brim
  • Pelvic cavity
  • Pelvic girdle
  • Pelvic inlet
  • Pelviperitonitis
  • Pelvis
  • Pendular movement
  • Penetrance
  • Penetration
  • Penile spine
  • Penis
  • Penis erection of the
  • Pennate muscle
  • Penniform muscle
  • Pentadactyl Limb
  • Pentapeptide
  • Pentose
  • Pentose phosphate pathway
  • PEP carboxylase
  • PEPC
  • Pepo
  • Peptic ulcer
  • Peptide
  • Peptide bond
  • Peptide hormone
  • Peptidoglycan
  • Peptone
  • Perception
  • Perceptual closure
  • Perceptual distortion
  • Perch
  • Perennation
  • Perennial
  • Perfect flower
  • Perfect fungi
  • Perforations
  • Perfusion
  • Pericardium
  • Pericarp
  • Pericentric inversion
  • Periderm
  • Perimysium
  • Perineum
  • Perineurium
  • Perinuclear space
  • Periocular
  • Period
  • Periosteum
  • Peripatric speciation
  • Peripheral
  • Peripheral membrane protein
  • Peripheral nervous system
  • Periphery
  • Periphyton
  • Perisinusoidal space
  • Peristalsis
  • Peristolic
  • Peritoneoscopy
  • Peritoneum
  • Peritonism
  • Peritonitis
  • Permeability
  • Permeable
  • Permease
  • Permutation
  • Peroxidase
  • Peroxisome
  • Perpendicular fasciculus
  • Perpetuating factors
  • Persistence
  • Person-years
  • Perspiration
  • Pes
  • Pes valgus
  • Pes varus
  • Pest
  • Petal
  • Petaloid
  • Petiolate
  • Petiolate plant
  • Petiole
  • Petri dish
  • Petrotympanic fissure
  • PGA
  • PH Scale
  • Phagedenic ulcer
  • Phagocyte
  • Phagocytosis
  • Phagolysosome
  • Phagosome
  • Phagotrophy
  • Phalanges
  • Phantom
  • Pharmaceutical preparations
  • Pharmacology
  • Pharynx
  • Phasic
  • Phelloderm
  • Phenol
  • Phenol coefficient
  • Phenolase
  • Phenotype
  • Phenotype frequency
  • Phenotypic percentage
  • Phenotypic ratio
  • Phenylalanine
  • Pheomelanin
  • Pheromone
  • Phialides
  • Philippine tarsier
  • Phloem
  • Phloem fiber
  • Phloem parenchyma
  • Phloem sclerenchyma
  • Phobias
  • Phosphatase
  • Phosphate
  • Phosphate group
  • Phosphodiester bond
  • Phosphoenolpyruvate
  • Phospholipid
  • Phospholipid bilayer
  • Phosphorescence
  • Phosphoric Acid
  • Phosphorylation
  • Photic Zone
  • Photoautotroph
  • photobiology
  • Photodecomposition
  • Photoheterotroph
  • Photolithotrophic autotroph
  • Photolysis
  • photomedicine
  • Photometers
  • Photon
  • Photoperiodism
  • Photophobic
  • Photoreceptor
  • Photorespiration
  • Photosynthesis
  • Photosystem
  • Photosystem I
  • Photosystem II
  • Phototaxis
  • Phototroph
  • Phototropism
  • Phycobilin
  • Phycology
  • Phyletic gradualism
  • Phyletic lineage
  • Phyllode
  • Phylogenetic tree
  • Phylogenetics
  • Phylogeny
  • Phylum
  • Physalia physalis
  • Physical containment
  • Physical endurance
  • Physical fitness
  • Physical science
  • Physicology
  • Physiological
  • Physiological adaptation
  • Physiological processes
  • Physiology
  • Phytochrome
  • Phytoflagellate
  • Phytohemagglutinin
  • Phytohormones
  • Phytomastigophora
  • Phytoplankton
  • Pial-glial membrane
  • Pictograph
  • Pigment
  • Piles
  • Pili
  • Pillar cells
  • Pills
  • Pine
  • Pineal gland
  • Pinealocyte
  • Pinocytosis
  • Pinworm
  • Pioneer plant
  • Pioneer species
  • Piscivore
  • Pistillate
  • Pit
  • Pitcher
  • Pith
  • Pituicyte
  • Pituitary gland
  • Pivot
  • Placenta
  • Placental mammal
  • Placentalia
  • Planar chromatography
  • Planaria
  • Plane
  • Plane suture
  • Plankton
  • Plant
  • Plant association
  • Plant cell
  • Plant extracts
  • Plantae
  • Plantar
  • Plantations
  • Plantigrade
  • Plants edible
  • Plaque assay
  • Plaque-forming unit
  • Plaques
  • Plasma
  • Plasma B cell
  • Plasma volume
  • Plasmablast
  • Plasmid
  • Plasmodesmata
  • Plasmodium
  • Plasmolysis
  • Plaster of paris disease
  • Plastic embedding
  • Plastid
  • Platelet
  • Platyrrhine
  • Pleiotropy
  • Pleocytosis
  • Pleomorphic
  • Plica caecalis vascularis
  • Plica vestibularis
  • Ploidy
  • Plp
  • Plumage
  • Plume
  • Plumes
  • Plums
  • Plumule
  • Plural pregnancy
  • Pluripotent
  • Pneumatophore
  • Pneumomycosis
  • Poa
  • Pod
  • Poietin
  • Poikilotherm
  • Point mutation
  • Poison
  • Pol gene
  • Polar
  • Polar body
  • Polar compound
  • Polar molecule
  • Polar solvents
  • Polarity
  • Polarization
  • Polarized light
  • Polenske number
  • Poles
  • Pollen Grain
  • Pollex
  • Pollutant
  • Pollution
  • Pollux
  • Poly
  • Poly a tail
  • Polyadenylation
  • Polycythemia
  • Polygamy
  • Polygene
  • Polygenic disease
  • Polygenic inheritance
  • Polygenic trait
  • Polymenorrhoea
  • Polymer
  • Polymerase
  • Polymerization
  • Polymorph
  • Polymorphism
  • Polynucleotide
  • Polyol
  • Polyp
  • Polypeptide
  • Polyphyletic
  • Polyploid
  • Polyploidy
  • Polypoid
  • Polyprotein
  • Polysaccharide
  • Polysomy
  • Polyspermia
  • Polyspermy
  • Polytene chromosome
  • Polytomous key
  • Polyunsaturated fatty acid
  • Polyvalent
  • Pomes
  • Pomology
  • Pondweed
  • Pons
  • Pooled serum
  • Poorly drained soil
  • Popliteal line
  • Population
  • Population characteristics
  • Population density
  • Population genetics
  • Population pyramid
  • Pores
  • Port
  • Portal caval system
  • Portal vein
  • Portal-systemic anastomoses
  • Porter
  • Portio minor nervi trigemini
  • Positional cloning
  • Positive feedback
  • Postanal gut
  • Postencephalon
  • Posterior
  • Posterior tympanic artery
  • Postmortem
  • Postsynaptic
  • Postsynaptic cell
  • Postulate
  • Potato
  • Potato nose
  • Potato tumour of neck
  • Potency
  • Potential energy
  • Potential resource
  • Potentiality
  • Pouch of douglas
  • Pouches
  • Pp
  • Pre-ejaculate
  • Preadaptation
  • Preauricular
  • Prechiasmatic sulcus
  • Precipitate
  • Precipitating factors
  • Precursor
  • Precursor mRNA
  • Predation
  • Predator
  • Predator-prey relationship
  • Predisposing factors
  • Pregnancy
  • Prehensile
  • Prehensile tail
  • Prehension
  • Premature contact
  • Premaxillary suture
  • Preoral gut
  • Prepuce
  • Preputium clitoridis
  • Prescription
  • Preservation
  • Presynaptic
  • Presynaptic cell
  • Presynaptic terminals
  • Prevalent
  • Prey
  • Prezone
  • Pribnow box
  • Prickles
  • Primary cell wall
  • Primary consumer
  • Primary Growth
  • Primary meristem
  • Primary oocyte
  • Primary phloem
  • Primary producers
  • Primary productivity
  • Primary structure
  • Primary succession
  • Primary transcript
  • Primary xylem
  • Primase
  • Primate
  • Primer
  • Primer extension
  • Primiparity
  • Primiparous
  • Primitive
  • Primordial
  • Prion
  • Prions
  • Private blood group
  • Pro-
  • Probability
  • Probe
  • Probiosis
  • Problem
  • Proboscis
  • Procambium
  • Process
  • Prochordal plate
  • Procollagen peptidase
  • Prodromal period
  • Prodromal stage
  • Producer
  • Product
  • Proerythroblast
  • Profusion
  • Progenitor
  • Progenitor cell
  • Progeny
  • Progesterone
  • Progestogen
  • Prognathous
  • Prohormone
  • Projections
  • Prokaryote
  • Prokaryotic cell
  • Prolactin
  • Prolactin-releasing hormone
  • Prolamellar body
  • Proliferation
  • Proliferative inflammation
  • Promastigote
  • Promegakaryocyte
  • Prometaphase
  • Promoter
  • Promoter gene
  • Promoter insertion
  • Pronation
  • Pronucleus
  • Propagate
  • Propagated thrombus
  • Propepsin
  • Prophase
  • Prophase I
  • Prophase II
  • Proplastid
  • Proportion
  • Proprioception
  • Proprioceptor
  • Prosimian
  • Prostacyclin
  • Prostaglandin
  • Prostaglandin F2-alpha
  • Prosthetic group
  • Protective factors
  • Protein
  • Protein coat
  • Protein domain
  • Protein pump
  • Protein synthesis
  • Proteinoplast
  • Proteobacteria
  • Proteoglycan
  • Proteolytic Enzyme
  • Proteome
  • Prothorax
  • Prothrombin
  • Protist
  • Protista
  • Protistology
  • Proto-oncogene
  • Protocell
  • Protoderm
  • Protomer
  • Proton
  • Proton donor
  • Proton gradient
  • Proton-motive force
  • Protonema
  • Protonophore
  • Protophloem
  • Protoplasm
  • Protoplast
  • Protoscience
  • Prototherian mammal
  • Protoxylem
  • Protozoa
  • Protozoan cyst
  • Protozoology
  • Protrusions
  • Protuberance
  • Provacuole
  • Providencia alcalifaciens
  • Providencia rettgeri
  • Provirus
  • Provisional denture
  • Provitamin d3
  • Proximal
  • Prune
  • Pseudocoelomate
  • Pseudodominance
  • Pseudogamy
  • Pseudopodia
  • Pseudostratified columnar epithelium
  • Pseudostratified epithelium
  • Pseudovitamin b12
  • Pseudoxanthoma cell
  • Psychic determinism
  • Psychological techniques
  • Psychrometer
  • Psychrophile
  • Pteron
  • Pterygomandibular raphe
  • Pterygomaxillary notch
  • Ptyalin
  • Pubic
  • Pubic region
  • Pubis
  • Puffball
  • Pulmonary circulation
  • Pulmonary hypostasis
  • Pulmonary valve
  • Pulmonary ventilation
  • Pulmonary venule
  • Pulsatile flow
  • Pulse
  • Pulse deficit
  • Pulse-chase experiment
  • Pulsus magnus
  • Pulsus parvus et tardus
  • Pulvinus
  • Pump
  • Pumpkin
  • Punctate
  • Punctuated equilibrium
  • Punctum caecum
  • Punctum proximum
  • Punnett Square
  • Pupil
  • Pupillary light reflex
  • Pure science
  • Purebred
  • Purine
  • Purulence
  • Purulent
  • Purulent exudate
  • Pus
  • Pus cell
  • Pus corpuscle
  • Pussy
  • Putative
  • Putnam-dana syndrome
  • Putrefaction
  • Pyramid of Numbers
  • Pyramid of Productivity
  • Pyriform
  • Pyrimidine
  • Pyrogen
  • Pyrophosphate
  • Pyruvate
  • Pyruvic acid
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