MCQ
Antigens are present.
- AInside the nucleus.
- BOn cell surface.
- CInside the cytoplasm.
- DOn nuclear membrane.
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Aplysia, Asterias, Antedon, Echinus
$II.$ It comprises dead elements
$III.$ It comprises highly lignified cell wall
$IV.$ It is the peripheral part
$V.$ It is dark and tough
Which of the above property doesn't belongs to heart wood?