Topic 9: Plant Science. Modified from S. Taylor, S. Frander and L. Ferguson. 9.1.2 Outline 3 differences between the structures of dicotyledonous plants and monocotyledonous plants.
Modified from S. Taylor, S. Frander and L. Ferguson
Distribution of Tissues in Stem and Leaf of
Surface view of a spiderwort
(Tradescantia) leaf (LM)
(a) Cutaway drawing of leaf tissues
Cross section of a lilac
(Syringa)) leaf (LM)
9.1.3 Explain the relationship between the distribution of tissues in the leaf and the functions of these tissues.Absorption of light—parenchyma chloroplasts (ground tissue)Gas exchange stomata in epidermis--(controlled by epidermis guard cells) (dermal)Water conservation--cuticle produced by epidermis (and guard cells ) (dermal) Transport of water—xylem (vascular tissue)Transport of products of photosynthesis—phloem (vascular tissue)
Bulbs are vertical, underground shoots consisting mostly of the swollen bases of leaves that store food
Stem tubers are the swollen ends of underground stems that are specialized for storing food.
Storage roots are taproots that store food. The plant consumes this food during flowering and fruit production.
Tendrils modified stems or leaves as seen in climbing plants; provide flexible support
Meristem—plant tissue that remains embryonic for the life of the plant, allowing for growth throughout life, since they divide by mitosis.
9.1.6 Compare growth due to apical and lateral meristems in dicotyledonous plants.
Apical –primary (vertical) growth
--enables plant to reach light
Lateral--secondary (lateral) growth; form from cambium
--replaces epidermis with bark
--adds new vascular rings each year
Primary growth in stems
Shoot tip (shoot
and young leaves)
Secondary growth in stems
Proteins calledphototropinsabsorb light and bind to receptors that stimulate transcription of (growth)elongation genes in the cells, with the most auxin produced in the shaded cells.