The Parts of a Plant

What Plant Part Is It? Stem, Leaf, Root, Flower, Fruit, Seed? Fruit/Vegetable Part of Plant Broccoli Cabbage Carrot Celery Stalk Corn Kernel Onion Potato Tomato Zucchini

A) SHOOTS AND ROOTS The resources that a terrestrial plant needs are in two different places: Sunlight, CO 2 and O 2 are above ground water and minerals are in the soil Plant parts are specialized for acquiring these different resources

Plants have two main organ systems Shoot system Root system

1) The shoot system is above ground and includes organs such as leaves, buds, stems, flowers (if the plant has any), and fruits (if the plant has any) blade petiole lateral bud stem vascular tissue apical bud leaf Shoot system Root system

Leaves absorb sunlight and gases (CO 2, O 2 ) provide food (sugar) for the entire plant through photosynthesis

Stomata (singular: stoma) are openings in the underside of the leaf that allow gases (CO 2 and O 2 ) to enter and leave. They also allow water evapouration Guard cells Stoma

2) The root system includes those parts of the plant below ground, such as the roots, tubers, and rhizomes apical bud blade petiole lateral bud stem vascular tissue primary root lateral root root hairs leaf Shoot system Root system

Roots absorb water and minerals from the soil.

root hairs increase surface area for absorption

roots also anchor the plant to the “substrate” (ground)

B) PLANT TISSUES Plant organs are made up of 3 types of tissues: 1) Dermal tissue 2) Ground tissue 3) Vascular tissue

1) Dermal Tissue covers the outer surface of herbaceous plants Made up of epidermal cells in stems and leaves, covered by a cuticle, a waxy layer that prevents water loss

2) Ground Tissue most of the interior of the plant functions in synthesis of sugars, storage and support

3) Vascular tissue a system of tubes that distribute water, minerals, hormones and sugars throughout the plant

xylem tubes bring water and minerals from the roots up to the leaves (“water the xylem”)

xylem tubes also have strong walls that also function to support plants and hold them upright

phloem tubes distribute sugars from the leaves to the rest of the plant (“feed the phloem”)

A look at the vascular system of a pine tree:

take a cross-section of the trunk

A cross-section of a trunk or stem of a pine tree: wood inner bark outer bark

A cross-section of a trunk or stem of a pine tree: wood = xylem inner bark = phloem outer bark

a closer look: wood = xylem inner bark = phloem outer bark

C) PLANT GROWTH Plant growth occurs in areas called meristems Cells in these areas are undergoing mitotic division

Apical Meristem located at tips of roots and shoots allows increase in height/length Lateral Meristem located in cylinders within the plant body allows increase in width