Question

the mid ribs of leaves are primary composed of​

Answer 1

Explanation:

the mid ribs of leaves are primarily composed ofThe central or principal vein of a leaf. The central vein, or rib, of a leaf, usually running from the stem to the apex. The central or main vein of a leaf, as in eudicots, magnoliids, and ferns.

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Answer 2

Answer:

The central or principal vein of a leaf. The central vein, or rib, of a leaf, usually running from the stem to the apex. The central or main vein of a leaf, as in eudicots, magnoliids, and ferns.