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· An explanation grounded in the cited sources

Spruce needles

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How it works

Needles provide an accessible starting point for exploring a spruce. Picea abies typically has four-sided needles about 1–2.5 cm long.

[1]
Evidence for this statement

Source-based explanation

These dimensions belong to the Picea abies account in the European Atlas of Forest Tree Species. They should not be assigned to every spruce or used as the sole identification character.

[1]
Evidence for this statement

Source-based explanation

Connected concepts

Leaf

A leaf is an organ of a vascular plant. Its structure can be explored from the whole leaf to tissue, cell and chloroplast.

[2] [3]
Evidence for this statement

Source-based explanation

Photosynthesis

Photosynthesis synthesises organic compounds, including carbohydrates, from carbon dioxide using light energy. Gene Ontology identifies it as the biological process GO:0015979.

[4] [5]
Evidence for this statement

Source-based explanation

Continue with an organism

The photographs and molecular record come from separate source materials.

Norway spruce →Arabidopsis thaliana →

Your research question

Save the article to return to your question and this source version.

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Sources and versions

An explanation grounded in the cited sources

  1. Caudullo, Tinner & de Rigo · Picea abies in Europe · p.114

    2026-09-06 · Reuse permission unverified

    Provenance and original
    Source version
    2016
  2. Plant Ontology · 2026-01-09

    2026-09-04 · CC-BY-4.0

    Provenance and original
    Source version
    2026-01-09 / f5e2a95d88fe08af22f49e522cc78481d990a0b0
  3. Arabidopsis thaliana basal leaf; photographed 14 April 2021

    Retrieval date unknown · CC BY-SA 4.0

    Provenance and original
    Original SHA-256
    4c0da1e60a566728712e6443d8dfa11d4f4cd0084a0ef454d1262a3cdf05fa39
    Processing
    Resized and encoded as WebP; original 5 mm scale retained.
  4. GO:0015979 · photosynthesis

    2026-09-09T01:17:01.233038+00:00 · CC-BY-4.0

    Provenance and original
    Original SHA-256
    8649763135938e40bdb112c62e870749510eea1b750ff5d230a3061be5a3e017
    Processing
    Unmodified provider response; article text is an attributed educational summary.
    Version details
    QuickGO response did not supply a native ontology release; retrieval time and exact response hash retained.

    View original JSON · Download original

  5. GO:0009523 · photosystem II

    2026-09-09T01:17:35.068503+00:00 · CC-BY-4.0

    Provenance and original
    Original SHA-256
    56537702684f4e6949eb9b16430a8830740bc9fd3369b21e7b5a9b711a341b4f
    Processing
    Unmodified provider response; article text is an attributed educational summary.
    Version details
    QuickGO response did not supply a native ontology release; retrieval time and exact response hash retained.

    View original JSON · Download original

Inspect structured data
Content version
8788d7f3998f0f563e8d0782fce18f5bd3b27c2daae3f84d4aef511b155b2d5c
Source version
knowledge-20260909.1
Updated
2026-09-09