Introduction
Plants are autotrophs which make their own, organic nutrients, to sustain themselves, through a complex process known as photosynthesis. The plant kingdom is diverse and is made of plants of different biological diversity (Raven et al. 2005). Cryptograms or Seedless plants are vascular plants that do not produce seeds for dispersal but reproduce by windblown spores. In seedless plants the gametophyte and sporophyte are both independent phases in the plant’s life cycle. Like all vascular plants, cryptograms have true roots, stems and leaves. The sperm are flagellated and require water for reproduction. These plants are therefore limited to moist areas. It is hypothesized that many of the seedless vascular plants were once tree-sized at a point in time ("Lycopodium" September 28, 2012).
Table 1: Various plants within the plantae kingdom and their key characteristic/s.
Cryptograms and Vascular Tissue
The word vascular is synonymous with the word transport. Vascular tissue is the complex network of transport present within plants that help transport water and organic nutrients throughout the plants body. With vascular plants approximately 93% of their tissue is vascular. There are two main types of vascular tissue, the phloem and the xylem (Gregory).
Xylem
The xylem is composed of two types of elongated water-conducting cells. Tracheids along with fibres and parenchyma cells make up the xylem. The xylem’s function in the plant is to transport water and salts through the plant ("Vascular Tissues in Plants" 2004).
Phloem
The phloem unlike the xylem consist of living tissue called sieve tube elements, which consist of the sieve tube and a companion cell. The sieve tube elements along with sclereids and parenchyma make...
... middle of paper ...
...n Trinidad and Tobago. I would strongly recommend a checklist be done as soon as possible by the National Herbarium of Trinidad and Tobago. The limitations in this research are numerous
Works Cited
Peter Raven, Ray Evert, and Susan Eichhorn. 2005. “Biology of Plants.” New York: Freeman and Company.
Palaeos.org, "Lycopodium." Last modified September 28, 2012. Accessed November 19, 2013. http://www.palaeos.org/Lycopodium.
Gregory, Michael. The Biology Web, "Seedless Plants." Accessed November 19, 2013. http://faculty.clintoncc.suny.edu/faculty/michael.gregory/files/bio 102/bio 102 lectures/seedless plants/seedless plants.htm.
"Vascular Tissues in Plants," National Biology Support Service (NBSS) (2004): 1-2,
Radboud University Nijmegen, "Lycophyta (Lycopodium, Selaginella)." Accessed November 20, 2013. http://www.vcbio.science.ru.nl/en/virtuallessons/lycophyta/.
Many variations and species of plants can be found all around the world and in different habitats. These variations and characteristics are due to their adaptations to the natural habitat surrounding them. In three of many climatic zones, the arid, tropical and temperate zone, plants that vary greatly from each other are found in these locations. In this experiment, we’ll be observing the connection between the adaptations of the plants to their environment at the Fullerton Arboretum. The arboretum is a space containing numerous plants from different environments. The plants are carefully looked after and organized into their specific habitat. Therefore, we’ll be able to take a look at the plants within multiple
This cell membrane plays an important part in Diffusion. Cell membrane and Diffusion Diffusion is the movement of the molecules of gas or liquids from a higher concentrated region to a lower concentration through the partially permeable cell membrane along a concentraion gradient. This explanation is in the diagram shown below: [IMAGE] Turgor When a plant cell is placed in a dilute solution or a less concentrated solution then the water particles pass through the partially permeable membrane and fill the cell up with water. The cell then becomes Turgor or hard. An example of this is a strong well-watered plant.
As a result of these factors, the flora has adapted to these conditions in a variety of ways including their shape, leaf type, root system, and color. One of the most prominent adapt...
This gave rise to nonvascular plants like, mosses, liverworts, and hornworts. The second period of plant evolution began 425 million years ago was the diversification of plants with vascular tissue allowing plants to grow much taller and rise above the ground. The next period of plant evolution is the origin of seeds, about 360 million years ago. Seeds are embryos packed along with food in a protective covering. Last is flowering plants about 140 million years ago, which is seeds within protective chambers called ovaries. Animal evolution begins when an animals egg and sperm fuse, producing a zygote. The zygote splits by mitosis and forms an blastula, which usually is a hollow ball of cells. One side of the blastula folds in forming a gastrula, which develops into an embryo with a two-layered wall and an opening on one end. After the gastrula stage animals develop into
Schumann, Gail L., and Cleora J. D'Arcy. Hungry Planet: Stories of Plant Diseases. St. Paul: American Phytopathological Society, 2012. Print.
Janick. J. (2011). Center for New Crops & Plant Products - Department of Horticulture and
...hroughout the Eelgrass. Excess water in the form of vapor is disposed of through stomata on the leaves. The gas exchange, root, and shoot systems are used in this exchange because the stomata release the excess water in the form of water vapor, which was first absorbed by the roots in the root system, then transported through the xylem in the shoot system throughout the eelgrass. Another exchange that goes on in Eelgrass is nutrients to plant cells. Again the gas exchange, root, and shoot systems are used. Nutrients are absorbed by the roots and made through photosynthesis; stomata take in carbon dioxide which is used along with light, water, and other nutrients previously stored to make more. Nutrients are carried throughout the plant to plant cells by the phloem. Homeostasis is the balance of systems in organisms and it’s very important to keep them in balance.
Colgan, Wes III, Ramsey, Linda, White, James D., and Spaulding, Jim. Explorations in Biology. 6th ed. Boston: Pearson, 2010. 33-36. Print.
Plant defences are those mechanisms employed by plants in response to herbivory and parasitism. According to Hanley et al. (2007), “the tissues of virtually all terrestrial, freshwater, and marine plants have qualities that to some degree reduce herbivory, including low nitrogen concentration, low moisture content, toxins or digestibility-reducing compounds”. The type of chemical defence may be species specific (Scott 2008). The defences that plants possess may be in the form of chemical production or in the form of physical defences such as thorns or spikes and even through reinforced, rigid leaves. “The compounds that are produced in response to herbivory can either have a direct effect on the attacker itself (e.g. toxins or digestibility reducers), or serve as indirect defenses by attracting the natural enemies of the herbivores” (Bezemer & van Dam 2005). This essay will focus on chemical plant defences and in particular the effects of terpenes, phenolics, nitrogen-based defences as well as allelopathy in plants.
The plants that we know today as terrestrial organisms were not always on land. The land plants of today can be linked back to aquatic organisms that existed millions of years ago. In fact, early fossil evidence shows that the earliest land plants could have arisen some 450 million years ago (Weng & Chappie 2010). Plants that used to reside strictly in water were able to adapt in ways that allowed them to move onto land. It is speculated the need for plants to move onto land was created by water drying up, causing plants to have less room and pushing them to move onto land. Although the exact cause of plant’s need to move to a terrestrial environment is unclear, it is known that plants had to undergo several adaptations to be able to live on land. These adaptations include: lignin, cellulose, suberin, and changes to plant’s surface, including the formation of a waxy cuticle.
own roots (not just the plant kind), this meant they needed a structure that was different than
"Home | American Society of Agronomy." Home | American Society of Agronomy. N.p., n.d. Web. 25 Mar. 2014. .
Asexual propagation is the process through which reproduction without passage through the seed cycle occurs. The advantages of asexual propagation are that it preserves genetic makeup, propagates seedless plants, disease control, rapid production, the plants are identical, cheaper, faster and easier reducing or avoiding juvenility. The disadvantages of asexual propagation are that it increases disease and insect susceptibility, plants are bulky, and the mother plants could become contaminated. The goal of this experiment was to determine the development of adventitious roots and shoots, and observe these plants over a period of five weeks. Due to auxin being produced in the tip, tip cuttings should root faster than any other cuttings. Auxin is a plant hormone that is responsible for cell elongation and enlargement, root formation, and growth. There are two forms of auxins; phototropism, which is produced in the tip and moves downward on the side away from the light and gravitropism, which is where plant roots grow downward and plant shoots grow upward.(Plant Auxin 201...
Osmosis is the passage of water molecules from a weaker solution to a stronger solution through a partially permeable membrane. A partially permeable membrane only allows small molecules to pass through, so the larger molecules remain in the solution they originated in. Solute molecule [IMAGE] [IMAGE] Water molecule [IMAGE] The water molecules move into the more concentrated solution. When water enters a plant cell it swells up. The water pushes against the cell wall and the cell eventually contains all that it can hold.
For many years, nature has cloned organisms. When a plant sends out a stalk and it takes root, the new ...