1.0 Introduction

"Gymnosperms" include all seed plants other than the angiosperms, or flowering plants. The absence of an enclosing structure is believed to be primitive, thus the first seed plants were "gymnosperms." The seeds of "gymnosperms" are borne exposed in open structures, such as cones or leaves. The derivation of the word "gymnosperm" means naked seeds and is from the Greek wordsgymnomeaning naked or bare andspermmeaning seed. Fossil records indicate "gymnosperms" originated in the Paleozoic Era, during the middle Devonian Period about 390 million years ago, and reached their greatest diversity during the Mesozoic Era, between 60 to 225 million years ago. Although the "gymnosperms" were at one time treated as one closely allied group, many modern workers recognize several major groups, which include the commonly known conifers, cycads, and ginkgos, and the lesser known gnetopsids group, extinct progymnosperms, and extinct seed ferns. (Hilton, et.al., 2008).

The angiosperms, or flowering plants, are one of the major groups of extant seed plants and arguably the most diverse major extant plant group on the planet, with at least 260,000 living species classified in 453 families (Judd et al., 2002; APG II, 2003; Soltis et al., 2005). They occupy every habitat on Earth except extreme environments such as the highest mountaintops, the regions immediately surrounding the poles, and the deepest oceans. They live as epiphytes (i.e., living on other plants), as floating and rooted aquatics in both freshwater and marine habitats, and as terrestrial plants that vary tremendously in size, longevity, and overall form. They can be small herbs, parasitic plants, shrubs, vines, lianas, or giant trees. There is a huge amount of diversity in chemistry (often as a defense against herbivores), reproductive morphology, and genome size and organization that is unparalleled in other members of the Plant Kingdom. Furthermore, angiosperms are crucial for human existence; the vast majority of the world's crops are angiosperms, as are most natural clothing fibers. Angiosperms are also sources for other important resources such as medicine and timber. (Cole, et.al., 2009).

Objectives of this experiment are to describe the features of seed plant life cycle and the concept of the dominant generation, to describe the life histories and related reproductive structures of gymnosperms and angiosperms, to summarize the features that distinguish gymnosperm and angiosperm, and to discuss the advantages of seed plants to dominate land and their evolutionary adaptations of land.

2.0 Materials2.1 Gymnosperm 2.1.1 Living specimens of gymnosperm2.1.2 Compound microscope2.1.3 Dissecting microscope2.1.4 Slide and coverslip2.1.5 Forceps2.1.6 Distilled water

2.2 Angiosperm2.2.1 Living specimens of angiosperm :2.2.1.1 Dicots and monocots with rots, stems, leaves, flowers, fruits and seeds2.2.2 Compound microscope2.2.3 Dissecting microscope2.2.4 Slide and coverslip2.2.5 Forceps2.2.6 Distilled water

3.0 Procedure3.1 Gymnosperm3.1.1 Pine 3.1.1.1 Differentiate between male and female cone of Pinus sp.3.1.1.2 Longitudinal section of female and male cone examined. Megasporopyll, microsporophyll, megasporangia, microsporangia, ovule and pollen grains.3.1.1.3 Examined the fertilization occurred.3.1.1.4 Mature seed cone obtained. 3.1.1.5 Anotomy of pine leaf examined. Epidermis, stoma, photosynthetic mesophyll, endodermis, phloem, xylem, and resin duct identified.

3.2 Angiosperm3.2.1 Leaves3.2.1.1 Morphology of leaf arrangements and leaf venation.3.2.1.2 Structure of the leaves studied. Common features such as cuticle, air space, lower epidermis, upper epidermis, palisade mesophyll, spongy mesophyll, and vascular bundle.

3.2.2 Flowers3.2.2.1 Longitudinal section of some flowers observed. Parts of the flower named such as stigma, pistil, style, ovary, sepal, receptacle, peduncle, petal, filament stamen, and anther.

3.2.3 Fruits and Seeds3.2.3.1 Fruit wall, cotyledon, plumule of embryo, embryo, radical, cotyledon, seed coat, pericarp, mesocarp,endocarp, locule, and placenta identified.

4.0 Results

4.1 Gymnosperm

Pine

4.2 Angiosperm4.2.1 Leaves

4.2.2 Flowers

HibiscusAllamanda

4.2.3 Fruits and seeds

JackfruitLangsat

AppleBanana

Pineapple Orange

CornGuava

5.0 Post Lab Questions5.1 How to distinguish between a male and female cone of pine?The Male cone will form at the bottom of the tree and is muchsmaller than the female and the male produces the pollenand the female, produces the ovul and forms at the top of the tree.

5.2 Explain the characteristics of gymnosperm seeds to aid in dispersal.Unlike animals, plants are limited in their ability to seek out favorable conditions for life and growth. As a result, plants have evolved many ways todispersetheir offspring by dispersing their seeds (see alsovegetative reproduction). A seed must somehow "arrive" at a location and be there at a time favorable for germination and growth. When the fruits open and release their seeds in a regular way, it is calleddehiscent, which is often distinctive for related groups of plants; these fruits include capsules, follicles, legumes, silicles and siliques. When fruits do not open and release their seeds in a regular fashion, they are called indehiscent, which include the fruits achenes, caryopsis, nuts, samaras, and utricles. Seed dispersal is seen most obviously in fruits; however, many seeds aid in their own dispersal. Some kinds of seeds are dispersed while still inside afruitorcone, which later opens or disintegrates to release the seeds. Other seeds are expelled or released from the fruit prior to dispersal. For example,milkweedsproduce a fruit type, known as afollicle,that splits open along one side to release the seeds.Iriscapsulessplit into three "valves" to release their seeds

5.3 List the common characteristics of seed plants.All seed plants share two characteristics. They have vascular tissue and use seeds to reproduce. In addition, they all have body plans that include leaves, stems, and roots. Most seed plants live on land. Seed plants face many challenges, including standing upright and supplying all their cells with water and food. They meet these two challenges with vascular tissue. The thick walls of the cells in the vascular tissue help support the plants. In addition, water, food, and nutrients are transported throughout the plants in vascular tissue.There are two types of vascular tissue.Phloemis the vascular tissue through which food moves. When food is made in the plant's leaves, it enters the phloem and travels to the plant's stems and roots. Water and nutrients, on the other hand, travel in the vascular tissue calledxylem.The plant's roots absorb water and nutrients from the soil. These materials enter the root's xylem and move upward into the plant's stems and leaves. Seeds are structures that contain a young plant inside a protective coating. One reason why seed plants are so numerous is that they produce seeds. Seed plants do not need water in their environment to reproduce like seedless plants do. Even though different kinds of seeds look different from each other, they all have a similar structure. A seed has three important parts: an embryo, stored food, and a seed coat.

5.4 Contrast between dicots and monocots, the two classes of flowering plant.A dicot seed will look like a bean with two parts. Monocots haveparallel venation, fibrous root systems, lack true woody growth, flower parts come in multiples of threes, stems have scattered vascular bundles, pollen has one spore. Example : Palm trees, grasses, banana plants, orchids, bamboo, bromeliads. Dicots have net venation, taproot system, ma have woody growth, vascular bundels are in a ring, pollen has 3 spores, flowers in parts of 4 or 5. Example :Oak trees, tomato, lettuce, hibiscus, roses, apple tree.

5.5 Discuss the features of plant flowering fruits and seeds.Seedsdevelop from ovules in the ovary, and at maturity consist of anembryoand a reserve food supply surrounded by a protective covering, theseed coat. The diversity of flowering plants assures diversity among their seeds, but, unlike fruits, which have numerous variations, structural plans for seeds are few. The reserve food can be stored either in or out of the embryo and thecotyledon(s)the seed leavescan remain either below ground or be elevated above the surface when germination occurs. Fruits are ripened ovaries containing seeds with sometimes additional flower or inflorescence tissues associated with them. Only angiosperms produce flowers and fruits. From a botanical viewpoint, many of the foods we eat as vegetables are fruits, e.g. tomatoes, green beans, squash, eggplant, and peppers. Fruits apparently arose as a means not only of protecting the seeds, but as a way to ensure their dispersal.

6.0 Conclusion

7.0 References