If leaf, there is usually a middle prominent vein, which is known as the

The laryngeal prominence is usually more prominent in

A leaf that possesses more than one porminenet vein

Petiole part of the leaf is known as

Petiole part of the leaf is known as

Petiole part of the leaf is known as

Among various leaf factors, such as leaf age, leaf angle and leaf orientation, which has the most prominent effect on photosynthesis?