Difference between revisions of "SHELL"
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| − | + | <font size="3">| [[Shell size|size]] | [[composition]] | [[morphogenesis]] | [[shell architecture]] | [[functional morphology]] | |
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| + | {| width="80%" bgcolor="#fff4f4" id="toc" | ||
| + | !align="left" colspan="1"| [[Image:Bulbobaculites.jpg|thumb|right|122px|]] | ||
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| + | Most foraminifers construct tests (shells) covering the cell body. Composition of tests varies from organic, through agglutinated (cemented foreign grains) to calcareous secreted from calcium carbonate. | ||
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| + | The size of the test is associated with amount of the cytoplasm. "Feeding adds to the bulk of the cytoplasm" (Armstrong & Brasier 2005), therefore, the test has to enlarge. Foraminifera have developed several strategies for test enlargement during ontogeny (after Armstrong & Brasier 2005): | ||
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| + | - contained growth (see [[unilocular tests]] forms) | ||
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| + | - continuous growth (see [[unilocular tests|unilocular]] or [[bilocular tests]]) | ||
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| + | - simple septate growth (see [[simple multilocular tests]]) | ||
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| + | - complex septate growth (see [[complex multilocular tests]]) | ||
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| + | These growth patterns result in a very diverse variety of [[shell architecture|test morphologies]]. | ||
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| + | "The test is thought to reduce biological, physical and chemical stress" (Armstrong & Brasier 2005). See [[Function of the test]]. | ||
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| + | |} | ||
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[http://oceanworld.tamu.edu/students/forams/forams_test_construction.htm Foram test (shell) construction] | [http://oceanworld.tamu.edu/students/forams/forams_test_construction.htm Foram test (shell) construction] | ||
