LectureTopic21-Plant-Structure

Developmental plasticity

The ability to alter form in response to its environment.

Roots

Multicellular organs crucial for anchoring the plant, absorbing minerals and water, and storing organic nutrients.

Taproot system

A root system consisting of one main vertical root that gives rise to lateral roots.

Adventitious roots

Roots that arise from stems or leaves, not from the root system.

Fibrous root system

Characterized by thin lateral roots with no main root, common in seedless vascular plants and monocots.

Xylem

The vascular tissue that conveys water and dissolved minerals upward from roots into the shoots.

Phloem

The vascular tissue that transports organic nutrients from where they are made to roots and growth sites.

Parenchyma cells

Thin and flexible cells that perform most metabolic functions and retain the ability to divide and differentiate.

Collenchyma cells

Cells that support young parts of the plant shoot, providing flexible support without restraining growth.

Sclerenchyma cells

Highly specialized cells for mechanical rigidity, often dead at maturity and used for support.

Simple leaf

A leaf with a single undivided blade, sometimes deeply lobed.

Compound leaf

A leaf with multiple leaflets arising from the petiole.

Doubly compound leaf

A leaf where leaflets are divided again into smaller leaflets.

Stems

Organs that consist of nodes and internodes, facilitating the attachment of leaves and the support of the plant.

Apical dominance

The phenomenon where the apical bud suppresses the growth of axillary buds to control the plant's growth.

Root hairs

Tiny extensions of root cells that increase the surface area for water and nutrient uptake.

Modified roots

Adaptations such as prop roots, storage roots, and buttress roots to serve specific functions.

Modified stems

Adaptations like rhizomes, bulbs, and stolons that allow for asexual reproduction and storage.

Modified leaves

Adaptations such as tendrils, spines, and bracts that serve special roles in support, protection, and reproduction.