biology

Table of Contents

Introduction & Top Questions
Basic concepts of biology
- Biological principles
  - Homeostasis
  - Unity
  - Evolution
  - Diversity
  - Behaviour and interrelationships
  - Continuity
- The study of structure
  - Cells and their constituents
  - Tissues and organs
The history of biology
- The early heritage
  - Earliest biological records
    - Biological practices among Assyrians and Babylonians
    - Biological knowledge of Egyptians, Chinese, and Indians
  - The Greco-Roman world
    - Theories about humankind and the origin of life
    - Aristotelian concepts
    - Botanical investigations
    - Post-Grecian biological studies
  - The Arab world and the European Middle Ages
    - Arab domination of biology
    - Development of botany and zoology
    - Revitalization of anatomy
  - The Renaissance
    - Resurgence of biology
    - Advances in botany
    - Advances in anatomy
- Advances to the 20th century
  - The discovery of the circulation of blood
  - The establishment of scientific societies
  - The development of the microscope
    - Malpighi’s animal and plant studies
    - The discovery of “animalcules”
    - Swammerdam’s innovative techniques
    - Grew’s anatomical studies of plants
    - The discovery of cells
  - The development of taxonomic principles
    - The use of structure for classifying organisms
    - Reorganization of groups of organisms
  - The development of comparative biological studies
  - The study of the origin of life
    - Spontaneous generation
    - The death of spontaneous generation
    - The origin of primordial life
  - Biological expeditions
  - The development of cell theory
  - The theory of evolution
  - The study of the reproduction and development of organisms
    - Preformation versus epigenesis
    - The fertilization process
  - The study of heredity
    - Pre-Mendelian theories of heredity
    - Mendelian laws of heredity
    - Elucidation of the hereditary mechanism
- Biology in the 20th and 21st centuries
  - Important conceptual and technological developments
  - Intradisciplinary and interdisciplinary work
  - Changing social and scientific values
  - Coping with problems of the future

References & Edit History Related Topics

Images & Videos

biology; microscope

types of natural selection

Yersinia enterocolitica

Learn how Austrian Catholic monk and botanist Gregor Mendel observed properties of heredity

date palm; biology

Library of Alexandria

For Students

biology summary

Read Next

Endoplasmic reticulum. cell biology

6 Cell Organelles

Science studient dissecting frog

Pro and Con: Animal Dissection

H1N1 influenza virus particles. Colorized transmission electron micrograph. Surface proteins on surface of the virus particles shown in black. Influenza flu

10 Ways of Looking at Cells

Japanese spider crab

10 Animals With Evolutionary Traits Plucked Straight Out of a Nightmare

Spiral Galaxy type Sa-Sb or Sa/Sb in the constellation Virgo. The majestic Sombrero Galaxy Messier 104 (M104) or NGC 4594. The team took six pictures of the galaxy, stitched them together to create the final composite image. Photo from May-June 2003

9 Britannica Articles That Explain the Meaning of Life

Discover

Artist interpretation of a Space meteoroid impact. Meteor impact. Asteroid, End of the world, danger, destruction, dinosaur extinct, Judgement Day, Planet Earth, Doomsday Predictions, comet

10 Failed Doomsday Predictions

Periodical Cicada, Adult, Magicicada spp. Requires 17 years to complete development. Nymph splits its skin, and transforms into an adult. Feeds on sap of tree roots. Northern Illinois Brood. This brood is the largest emergence of cicadas anywhere

Why Do Some Cicadas Appear Only Every 17 Years?

Vietnam War. U.S. President Lyndon B. Johnson awards the Distinguished Service Cross to First Lieutenant Marty A. Hammer, during a visit to military personnel, Cam Ranh Bay, South Vietnam, October 26, 1966. President Johnson

Vietnam War Timeline

earthquake. Heavily damaged school in the town of Yingxiu after a major earthquake struck China's Sichuan Province on May 12, 2008.

The 6 Deadliest Earthquakes Since 1950

Adolf Hitler (Nazi, nazism, German leader).

9 Things You Might Not Know About Adolf Hitler

Queen Elizabeth II addresses at opening of Parliament. (Date unknown on photo, but may be 1958, the first time the opening of Parliament was filmed.)

All 119 References in “We Didn’t Start the Fire,” Explained

Black widow spider

9 of the World’s Deadliest Spiders

biology: Media

Videos

Learn how Austrian Catholic monk and botanist Gregor Mendel observed properties of heredity

Learn how Austrian Catholic monk and botanist Gregor Mendel observed properties of heredity

An introduction to Austrian botanist, teacher, and Augustinian prelate Gregor Mendel's...

Video: Encyclopædia Britannica, Inc.

biologist

biologist

Job description of a biologist.

Video: CandidCareer.com (A Britannica Publishing Partner)

Images

biology; microscope

biology; microscope

A researcher using a microscope to examine a specimen in the laboratory.

© Radu Razvan/Fotolia

cells

cells

Animal cells and plant cells contain membrane-bound organelles, including a distinct...

Encyclopædia Britannica, Inc.

types of natural selection

types of natural selection

Three types of natural selection, showing the effects of each on the distribution...

Encyclopædia Britannica, Inc.

Yersinia enterocolitica

Yersinia enterocolitica

Photomicrograph of Gram stain of Yersinia enterocolitica, the causative...

Centers for Disease Control and Prevention (CDC)(Image Number: 2153)

date palm; biology

date palm; biology

The Babylonians knew of the separate sexes of the date palm (Phoenix dactylifera)...

Grant Heilman/Encyclopædia Britannica, Inc.

Ebers papyrus

Ebers papyrus

Ebers papyrus prescription for asthma treatment.

U.S. National Library of Medicine/National Institutes of Health

Hippocrates

Hippocrates

Hippocrates, undated bust.

World History Archive/Alamy

Theophrastus

Theophrastus

Theophrastus, statue in the Botanic Garden, Palermo, Italy.

Esculapio

Library of Alexandria

Library of Alexandria

Illustration of the ancient Library of Alexandria, Egypt.

Fine Art Images/Heritage-Images/age fotostock

Saint Albertus Magnus

Saint Albertus Magnus

Saint Albertus Magnus, who worked to meld theology and Aristotelianism and was probably...

© Photos.com/Thinkstock

Vesalius, Andreas; anatomy

Vesalius, Andreas; anatomy

Woodcut depicting Renaissance physician Andreas Vesalius teaching anatomy, from the...

Photos.com/Thinkstock

microscope by Antonie van Leeuwenhoek

microscope by Antonie van Leeuwenhoek

Microscope made by Antonie van Leeuwenhoek.

Photos.com/Thinkstock

drawing of a female gnat by Robert Hooke

drawing of a female gnat by Robert Hooke

Drawing of a female gnat by Robert Hooke, from Micrographia (1665).

From Micrographia, by Robert Hooke, 1665

experiments disproving spontaneous generation

experiments disproving spontaneous generation

The hypothesis of spontaneous generation posited that living organisms develop from...

Encyclopædia Britannica, Inc.

anthrax protein

anthrax protein

This computerized image of anthrax shows the various structural relationships of...

University of Oxford/Getty Images

gene knockout

gene knockout

In gene knockout, a functional gene is replaced by an inactivated gene that is created...

Encyclopædia Britannica, Inc.

scale in ecological studies

scale in ecological studies

A forest patch nested within a landscape mosaic.

Encyclopædia Britannica, Inc.

VIEW MORE in these related Britannica articles: