living things

References

Images & Videos

This infographic compares the relative biomass in gigatons of carbon among major kingdoms of life, showing plants with the greatest biomass, followed by bacteria, fungi, archaea, protists, animals, and viruses. A detailed breakdown highlights that among animals, arthropods and fish have the highest biomass, with much smaller contributions from annelids, mollusks, livestock, humans, wild mammals, wild birds, nematodes, and cnidarians. Simple illustrations represent each group.

Diagram of the tree of life based on the three-domain system, showing Archaea, Bacteria, and Eukaryota branching into four kingdoms: Plants, Animals, Fungi, and Protista, with illustrations of representative organisms for each group.

See a survey comparing the largest known single living organisms on Earth: from the animal, plant, and fungal kingdoms

Eukaryotic vs. Prokaryotic Cells: Key Differences Explained

living things

Also known as: organism

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chemical compound
Organic compounds
…that can be described as living have a crucial dependence on organic compounds. Foodstuffs—namely, fats, proteins, and carbohydrates—are organic compounds, as are such vital substances as hemoglobin, chlorophyll, enzymes, hormones, and vitamins.
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…that can be described as living have a crucial dependence on organic compounds. Foodstuffs—namely, fats, proteins, and carbohydrates—are organic compounds, as are such vital substances as hemoglobin, chlorophyll, enzymes, hormones, and vitamins.
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genetic code
…to diverge slightly in certain organisms and in the mitochondria of some eukaryotes. Nevertheless, these differences are rare, and the genetic code is identical in almost all species, with the same codons specifying the same amino acids. The deciphering of the genetic code was accomplished by American biochemists Marshall W.…
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…to diverge slightly in certain organisms and in the mitochondria of some eukaryotes. Nevertheless, these differences are rare, and the genetic code is identical in almost all species, with the same codons specifying the same amino acids. The deciphering of the genetic code was accomplished by American biochemists Marshall W.…
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How Does Carbon Dating Work?
Step 2: Organisms take in carbon
Carbon enters living things as part of the compound CO₂. Plants absorb CO₂ as part of photosynthesis. Animals then eat the plants—or, in the case of carnivores, other animals that consumed plants—and thus take in the carbon.
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Carbon enters living things as part of the compound CO₂. Plants absorb CO₂ as part of photosynthesis. Animals then eat the plants—or, in the case of carnivores, other animals that consumed plants—and thus take in the carbon.
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vitamin
Requirements in living things
Vitamin requirements vary according to species, and the amount of a vitamin required by a specific organism is difficult to determine because of the numerous factors (e.g., genetic variation, relative proportions of other dietary constituents, environmental stresses). Although there is not uniform agreement…
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Vitamin requirements vary according to species, and the amount of a vitamin required by a specific organism is difficult to determine because of the numerous factors (e.g., genetic variation, relative proportions of other dietary constituents, environmental stresses). Although there is not uniform agreement…
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