Anatomy of Flowering Plants

Flashcards covering the internal structure, tissue systems, and anatomical differences between monocot and dicot plants based on lecture notes.

Epidermal Tissue System

The outermost layer of the plant body comprising the epidermis, stomata, and epidermal appendages like root hairs and trichomes.

Epidermis

The outermost, continuous layer of cells with no intercellular spaces (ICs) that often has a waxy cuticle to prevent $H_2O$ loss.

Stomata

Structures in the epidermis composed of a stomatal pore, guard cells, and subsidiary cells that regulate gas exchange ($CO_2$) and transpiration ($H_2O$ vapor).

Guard Cells

Cells that regulate the opening and closing of stomata; they are kidney-shaped in dicots and dumb bell-shaped in monocots.

Trichomes

Multicellular epidermal appendages found on stems that are secretory in nature and help protect the plant from pathogens and prevent water loss.

Root Hairs

Unicellular outgrowths of the epiblema responsible for the absorption of $H_2O$ and minerals from the soil.

Ground Tissue System

All tissues except epidermal and vascular tissues, including the cortex, pericycle, pith, and medullary rays, made of parenchyma, collenchyma, and sclerenchyma.

Mesophyll

The ground tissue in leaves containing chloroplasts and chlorophyll pigment, responsible for photosynthesis.

Cambium

A lateral meristem located beneath the bark region that helps in rapid cell division and responsible for the secondary growth of the plant.

Open Vascular Bundle

A type of vascular bundle where cambium is present between the xylem and phloem, allowing for secondary growth; characteristic of dicot stems.

Closed Vascular Bundle

A vascular bundle where cambium is absent, meaning no secondary growth occurs; characteristic of monocot stems and monocot roots.

Radial Arrangement

The arrangement of vascular bundles where xylem and phloem occur on different radii in an alternating manner, typical of roots.

Conjoint Arrangement

The arrangement of vascular bundles where xylem and phloem are situated on the same radius, typical of stems and leaves.

Epiblema

The outermost layer of the dicot root, also referred to as the piliferous layer.

Polyarch Condition

A condition in monocot roots where the number of xylem and phloem bundles is more than 6.

Dorsiventral Leaf

A dicot leaf characterized by stomata being absent or less abundant on the upper side and a mesophyll differentiated into palisade and spongy parenchyma.

Isobilateral Leaf

A monocot leaf where stomata are equally distributed on both sides and the mesophyll is undifferentiated.

Casparian Stripes

Thickenings found in the endodermis of roots; they are less prominent in dicot roots but highly thickened in young monocot roots.

Pith

The central region of the stem or root; it is absent or very small in dicot roots but well developed in monocot roots.