INTRASPECIFIC COMPETION: THE RESPONSE OF THE SUNFLOWER (genus HELIANTHUS) TO INCREASING DENSITY.
INTRODUCTION
All species, including plants, are impacted by density. Plants, of course, cannot leave their habitat as animals can, so they tend to respond in different ways to density. As populations grow more dense, they compete for resources such as food and space and are more prone to disease. Less dense populations are more susceptible to predation pressure.
It is hypothesized that as plants in small spaces compete for space, the plants compensate by reducing individual stem weight and frequency of bud formation as density increases. This would be intraspecific competition. A factor is density-dependent when it kills more of a population at higher densities and less at lower densities (Stilling 2002). The factor of competition between individual plants of the same species would be considered density dependent.
METHODS
The experiment was designed to test the hypothesis by planting an increasing number of genus Helianthus (sunflower) seeds in pots to see how they respond to increased density in limited space. Two replicates each of 2, 4, 8, 16, 32, 64, and 128 seeds were planted in similar size pots containing an equal mix of potting soil and perlite. All plants were kept in greenhouse conditions exposed to similar light and temperatures settings and were watered at equivalent intervals. At the end of the time period each pot was evaluated for number of seeds that had germinated as well as number of stems with blooms. Stems and blooms were cut and weighed.
RESULTS
Table 1 shows averages of each replicate for each series of seeds relating to mortality rate/germination rate, budding rate, and mean plant weight (total, with buds, and without buds).
Figure 1 indicates an increasing mortality rate (positive slope) in plants as density increases; Figure 2 shows the corresponding germination rate reflecting the exact opposite trend. Mortality remains zero until 8 seeds are planted (6% mortality), then is reduced to zero at 16 seeds then increases to 14 percent (32 seeds), 32 percent (64 seeds), and more than half (57 %--128 seeds).
Figure 3 shows a dramatic decrease in bud formation of approximately 20 percent from four to eight seed plantings, followed by slight decreases of 3 percent of less in bud formation as significantly greater quantities of seeds are planted.
Figure 4 reflects a decreasing mean weight per plant as density of planted seeds increases-- from a high of 11.73 grams (2 seeds) decreasing gradually from between 3 to .
Two members of the group were instructed to visit the laboratory each day of the experiment to water and measure the plants (Handout 1). The measurements that were preformed were to be precise and accurate by the group by organizing a standardized way to measure the plants. The plants were measured from the level of the soil, which was flat throughout all the cups, to the tip of the apical meristems. The leaves were not considered. The watering of the plants took place nearly everyday, except for the times the lab was closed. Respective of cup label, the appropriate drop of solution was added to the plant, at the very tip of the apical meristems.
Plastic surgery is defined as a procedure done to reconstruct body parts. It doesn't necessarily mean working with plastic, because the word plastic in plastic surgery is derived from the Greek word plastikos, which means ‘to mold’. (Straightdope) Many believe that a man called Sir Harold Delf Gillies did the first modern plastic surgery in 1917. During the World War I, he met a French surgeon called Hippolyte Morestin, who greatly influenced him. After carefully observing him removing a tumor,Sir Harold performed the flap surgery on a World War I soldier who injured himself badly on his face. While Sir Harold is still considered as the Father of Modern Plastic Surgery, people assume that the Indians were the first to perform plastic surgery back in 800 B.C. With this discovery, British physicians visited India to observe the native methods of plastic surgery. (Williams) Over the years, new discoveries are made, which also means that new forms of plastic surgery are constantly performed. As of now, there are various types of plastic surgery, all done on different body parts of a human. Plastic surgery is generally divided into two, reconstructive and cosmetic. ...
Every student in a lab section planted eight seeds, two in each cell in a quad, to make sure that we had at least one plant for each week for 4 weeks. After planting the seeds we put the plants on a water mat tray to make
Each Biology 108 section planted these pots and the data from every section was to be combined for an overall data sheet. Our group in section 6 had the role of planting 5 of the experimental pots with the assigned number of wheat seeds or mustard seeds or both.
...hese days and is no longer accessible only to the rich and famous. Any person in the world can have the procedure they want done. Men, women and parents of small children are making the decision things about their bodies and looks each day. Plastic surgery can improve a person’s self esteem or can drastically change the life of a child or adult with deformities. No matter what the reason may be, plastic surgery is not something that is to be entered into lightly. It requires a long thought process, a search for a good and credible practitioner, support from loved ones, possible therapy and of course, a lot of money. The decision to undergo cosmetic or reconstructive surgery is intensely personal. People, for reasons as simple as a crooked nose, to the lessening of a serious scar, to those deformed by birth, accidents or injury have options available to them.
In today society, beauty in a woman seems to be the measured of her size, or the structure of her nose and lips. Plastic surgery has become a popular procedure for people, mostly for women, to fit in social class, race, or beauty. Most women are insecure about their body or face, wondering if they are perfect enough for the society to call the beautiful; this is when cosmetic surgery comes in. To fix what “needed” to be fixed. To begin with, there is no point in cutting your face or your body to add or remove something most people call ugly. “The Pitfalls of Plastic Surgery” explored the desire of human to become beyond perfection by the undergoing plastic surgery. The author, Camille Pagalia, took a look how now days how Americans are so obsessed
Scaffolding is a term that appears frequently in the field of psychology. It is a term that is used to describe a form of teaching. According to Firestone, it is a technique in which teachers show their students how to find a solution to a problem. The teacher then “steps back” and allows for the student to try it on their own. This process is done to teach independence in problem solving onto the students (Firestone n.d.). Through the use of scaffolding, students are able to work on problems on their own, without having to necessarily “hold hands” with their instructor or teacher. Scaffolding is worth examining in the field of psychology because it is useful to see the development in the growth and knowledge of a child. The results of scaffolding are worth examining as well in order to see what the most effective ways of teaching are. There are many different ways in which teachers or instructors can inform their students how to solve a problem. In other words, there are many different scaffolding techniques. Because of this, the question of “what is the most frequently used scaffolding technique?” arises.
Which person in the whole world didn’t wish at some point in his/her life to go back in time? Whether it was to have another chance to correct our mistakes or grab an opportunity we once let go, we all wish to travel to the past. For some people, it is totally different. They want to go back in time not only to look but to also feel young again; and luckily for these people the solution has been found. Since ancient times people seek self-improvement and plastic surgery which is the reparation, reconstruction or change of body parts using surgical procedures, has never stopped evolving and improving to help them. For the past few decades plastic surgery has been increasing more and more, which raised the debate between those who accept it and those who oppose it and want it to stop especially when it is done for cosmetic rather than reconstructive purposes. Cosmetic surgery should not be trivialized, as it has many benefits and lead to favorable consequences.
Children love to draw even if that’s drawing on the wall of their home or creating a masterpiece on the table. If they are not satisfied with their drawing they can modify it and make it better to their extent. Plastic surgery is just that. It is changing or modifying the way someone looked for different reasons. Dating back to ancient times and its most basic form, plastic surgery has been apart of the world for many centuries (Kalantar-Hormozi, 2013). Since then it has advanced enormously and in society today any part of the body can be manipulated. Plastic surgery also called cosmetic or reconstructive surgery is acceptable for bullied victims, weight loss successors and accident survivors that undergo this ancient practice to better themselves
Poorter, H, and Navas, M. 2003. Plant growth and competition at elevated CO2: on winners, losers and functional groups. New Phytologist. 157: 175-198.
have up to 3 or 4 buds. Exactly the same as plants in soil, they use
Cosmetic Surgery is a great discovery that has been around for many centuries. “The history of plastic surgery origins in the early 800 B.C. when surgeons in India restored noses to persons who had them taken off as a form of punishment.” (History of Cosmetic Surgery, 2008) Many people have used over the years cosmetic and reconstructive surgery to enhance their physical appearance weather it be for health problems associated with birth defect or problems that they have developed over the years or to even alter physical appearances for instance nose jobs and tummy tucks. There are numerous types of cosmetic surgery that can be done today in the United States, over the year’s surgeons techniques have improved dramatically. There are a number of pro’s and con’s that go along with cosmetic surgery, such as the amount of recovery time and the initial cost of surgery. Statistics also show that cosmetic surgery has grown so rapidly over the years it is phenomenal people who receive cosmetic surgery goes up by the millions every year. While there can be many related health risks due to cosmetic sugary, many times cosmetic surgery is necessary and its is made more affordable than thought to be.
"Home | American Society of Agronomy." Home | American Society of Agronomy. N.p., n.d. Web. 25 Mar. 2014. .
This lesson is designed to review and reinforce a few important concepts about plants (e.g. Needs, parts, sequence of planting) and to also guide the students through applying a few scientific inquiry (e.g. Making observations, experimentation, discussion, reflection, reporting results etc.). The students have previously planted corn and bean seeds and today’s lesson has provided the students a chance to see the results of the planted corn and bean seeds. Additionally, seeds have been planted under and growing under the following conditions: without water, and without soil. The students see the results of these seeds planted under these conditions for the past week. Two plants in particular have already been grown their growth has been
...s. There would be severe overcrowding if they just fell where the parent plant is located meaning that the seeds would not get enough sunlight, water or space to grow and develop properly. If all members of a species were to be crowded together in one area it would make them more susceptible to risks such as fire or disease. By the dispersal of the seeds covering a wider area the chance of this happening would be greatly reduced (11). There for seed dispersal is necessary to help ensure as many seeds as possible have a chance to grow and develop properly, so that they are able to then develop seeds of their own (8). The loss of herbivores such as the wild ox (bos primigenius) in the Caledonian forest has deprived that area of an important dispersal agent but there are still other herbivores such as rodents that can still help maintain the dispersal of seeds (11).