imagination - the formation of a mental image of something that is not perceived as real and is not present to the senses; popular imagination created a world of demons; imagination reveals what the world could be. imaginativeness, vision. creative thinking, creativeness, creativity - the ability to create.
Definition of the Cortex. Let's explore the cortex layer in more detail. The cortex is defined as root and stem tissue found between the epidermis and vascular tissue of a plant. When you eat potatoes or carrots you are actually eating the root of a plant's cortex.
A leaf is an organ of a vascular plant and is the principal lateral appendage of the stem. The leaves and stem together form the shoot.Foliage is a mass noun that refers to leaves collectively. Typically a leaf is a thin, dorsiventrally flattened organ, borne above ground and specialized for photosynthesis.n ferns and most flowering plants, the mesophyll is divided into two layers: 1  An upper palisade layer of vertically elongated cells, one to two cells thick, directly beneath the adaxial epidermis, with intercellular air spaces between them. 2  Beneath the palisade layer is the spongy layer.