Photo Unit 1: The Plant Body

PHOTO UNIT 1: THE PLANT BODY

OBJECTIVES:

1. Recognize the major organs of the plant body.

2. Compare mature embryos of several species to show likenesses and differences.

3. Identify differences in embryonic development in photo series of representative species.

Why study plant anatomy?

Anatomy, etymologically speaking means ‘to cut up’. It is a way of studying the structure of the various organs to determine the nature of their internal parts, and gives us an opportunity to see how the various cell and tissue types perform to give structure to the plant body. From this we can draw inferences regarding the function on the basis of the structure.

One should take care to realize that the living plant body is an integration of all the organs working in unison. There are several series of photographs of developmental anatomy of various organs to help to understand the dynamic nature of plant growth from an anatomical viewpoint.

The organs of the plant.

The plant body consists of the shoot, which includes the stem, leaf, flower, fruit, seed. The stem serves primarily as a supporting organ for the leaf, and flower. The leaf is the primary photosynthetic organ. The flower is the reproductive unit of the plant. The fruit contains the seed(s). The seed assures the next generation of the plant. It also has a root, functioning as an anchoring agent as well as a nutrient and water absorbing organ. Early in the seedling development, cotyledon(s) are the first appendages of the stem, and the hypocotyl is that part of the shoot axis between the root and the stem.

In the beginning…

Your first opportunity to view photographs of anatomical structures include 3 series of embryonic development in barley, palm, and corn. Following this series, you will enter into the wonderful world of plant anatomy viewing photos, with accompanying descriptive and investigative narrative. We will study the anatomy on the cellular level and the tissue level for each of the major organs of the plant during its primary development (growth in length) and its secondary development (growth in diameter).

Photos for this study:

These photos represent stages in the development of three species of seed plants. See if you can follow the development of the various organs of the plant body as they differentiate at subsequent stages.

**Click on a picture to view a larger image**

1-1: Hordeum (Barley) Young embryo LP