septum

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septum

tissue

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July 13, 2026

Quick Summary

A septum is a dividing wall or membrane, particularly one that separates bodily spaces or masses of soft tissue. In the human body, a notable example is the nasal septum, which divides the nasal cavity into left and right passages.12

Septa also play a crucial role in the heart. An atrial septal defect is a congenital opening between the two upper chambers (atria) of the heart, allowing blood to flow from the left to the right atrium. Similarly, a ventricular septal defect is an opening between the lower chambers (ventricles). These defects can lead to various cardiovascular issues, with surgical closure often being the recommended treatment for significant openings.34

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aggressive behaviour
Neuroendocrine influences
…of the limbic system—specifically the septum, which lies above the hypothalamus and has an inhibitory effect on aggression, and the amygdala, found deep in the temporal lobes and having the opposite effect.
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…of the limbic system—specifically the septum, which lies above the hypothalamus and has an inhibitory effect on aggression, and the amygdala, found deep in the temporal lobes and having the opposite effect.
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moss animal
Budding
…of the colony are called septa. The growth and budding zones of the colony are found at its outer edges. Cells from the surface epithelium push inward to produce the polypide, and the septa create a chamber around it. The walled portion of a zooid is called the cystid.
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…of the colony are called septa. The growth and budding zones of the colony are found at its outer edges. Cells from the surface epithelium push inward to produce the polypide, and the septa create a chamber around it. The walled portion of a zooid is called the cystid.
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respiratory system
The lung
…subdivided by incomplete walls (septa), and between the larger septa are secondary septa that surround the air spaces where gas exchange occurs. The diameter of these air spaces (alveoli) in lower vertebrates is larger than in mammals: The alveolus in the frog is about 10 times the diameter of…
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…subdivided by incomplete walls (septa), and between the larger septa are secondary septa that surround the air spaces where gas exchange occurs. The diameter of these air spaces (alveoli) in lower vertebrates is larger than in mammals: The alveolus in the frog is about 10 times the diameter of…
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circulatory system
Amphibians
…salamanders, however, have no atrial septum, and one small and unfamiliar group, the caecilians, has signs of a septum in the ventricle. It is not known whether the original amphibians had septa in both atrium and ventricle. They may have, and the absence of septa in many modern forms may…
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…salamanders, however, have no atrial septum, and one small and unfamiliar group, the caecilians, has signs of a septum in the ventricle. It is not known whether the original amphibians had septa in both atrium and ventricle. They may have, and the absence of septa in many modern forms may…
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