Plant Biology Chapter: The Stem

The stem, alongside leaves and other aerial parts, forms the shoot system of plants.
Primary functions include providing support and facilitating water and solute transport between roots and leaves.
Some stems have modifications for specialized functions, e.g., photosynthesis, storage, and asexual reproduction.

Plant specimens: monocot & dicot stem terminal portions, specialized stems (potato, banana, ginger, bougainvillea, cactus, common lawn grass, and Cucurbitaceae).
Compound microscope.
Prepared cross-section slides of monocot and young dicot stems.
Prepared slide of dicot stem with secondary growth.

Examine terminal portions of monocot and dicot stems and identify parts: terminal bud, node, internode, leaf axil.
Analyze specialized stems and illustrate their functions.

Examine prepared slides of monocot and dicot stem cross-sections (Low Power Objective - LPO) to identify: pith, vascular bundle, xylem, phloem, sclerenchyma cells, cortex, and epidermis.
Assess vascular bundles in detail (High Power Objective - HPO), drawing them with labels such as bundle sheath cells, xylem, phloem, air space, fiber cap.
Analyze a prepared slide of a dicot stem with secondary growth, identifying parts: primary xylem, secondary xylem, xylem ray, vascular cambium, secondary phloem, phloem ray, periderm, bark, and lenticel.

Compare external features of monocot and dicot stems, highlighting distinctions between stems and roots.
Define axillary buds, their location, and functions.
Explain phyllotaxy and differentiate between types: spiral, distichous, opposite, decussate, and whorl.
Define cladodes or cladophylls and provide examples of two plant species.
Create a comparison table for: vascular cambium vs. cork cambium, ray initials vs. fusiform initials, softwood vs. hardwood, heartwood vs. sapwood, lenticels vs. stomata.
Enumerate the three tissues of the periderm.
Define bark and identify its included tissues.
Differentiate between observed steles in the activity.

Common names and scientific names for both types of stems are to be recorded.
Assess specialized stems from various plants and identify their functions, emphasizing the types and scientific names.