Biology

Articles about living organisms, life processes and biological research.

Articles in this category: 1554 Updated: April 29, 2026 Page 21 / 33

Neurodegeneration

Neuroethology

Neuroethology: the neural basis of natural animal behavior

Neuron

Neuron

Neuroscience

Neuroscience — the scientific study of the nervous system and brain function

Neurosecretion

Neurotoxin

Neutrophil

Neutrophil: frontline white blood cell in innate immunity

Niacin

Nicotinamide adenine dinucleotide phosphate

NADP and NADPH: cellular reducing coenzymes in biosynthesis and antioxidant defense

Nidovirales

Nidovirales: biology, families, and significance

Nipple

Nipple (mammary nipple)

Nitrogen cycle

Nitrogen cycle: processes, organisms, and environmental significance

Nomascus

Nomascus — the crested gibbons

Nomen dubium

Nomen dubium (doubtful name)

Non-coding DNA

Non-coding DNA: functions, types and scientific significance

Non-coding RNA

Non-coding RNA (ncRNA): types, roles and history

Nose

Nose: structure, function, health, and evolutionary context

Nostril

Notochord

Notochord: embryonic axial structure and evolutionary role

Novolac

Novolac (phenol–formaldehyde resin)

Nuclear DNA

Nuclear DNA: structure, inheritance, and role in eukaryotic cells

Nuclear membrane

Nuclear membrane (nuclear envelope)

Nuclease

Nuclease (enzyme that cleaves nucleic acids)

Nucleic acid

Nucleic acids: structure, function, and biological significance

Nucleobase

Nucleobase — fundamental bases of DNA and RNA

Nucleoid

Nucleoid (prokaryotic genetic region)

Nucleolus

Nucleolus: structure, function and role in ribosome production

Nucleosome

Nucleotide

Nucleus

Nucleus: central structures in cells, atoms, comets, and brains

Nucleus (brain)

Nucleus (brain structure)

Nutrient

Nutrient (biology)

Nutrition

Obazoa

Obazoa: a proposed eukaryote clade linking opisthokonts, apusomonads and breviates

Occipital bone

Occipital lobe

Octocorallia

Oestradiol

Oestradiol (E2): roles, biology, and clinical significance

Oestrogen

Oestrone

Oestrous cycle

Olfactory bulb

Olfactory system

Olfactory system: structure, function, and role in vertebrate behavior

Oligotroph

Oligotroph: organisms adapted to nutrient-poor environments

Omnivore

Omnivore

On the Origin of Species

On the Origin of Species — Charles Darwin's 1859 work

Oncogene

Oncogene: genes that promote uncontrolled cell growth

Online Mendelian Inheritance in Man

Online Mendelian Inheritance in Man (OMIM): a concise reference for human genes and phenotypes