Biology : Plant And Animal Responses

Phototropism is the growth of a plant in the direction of its light source. Phototropism occurs due to a hormone called auxin which is produced at shoot tips. Auxin influences cell division, if there is light on one side then the dark side will receive more auxin and therefore more cell division will occur on that side, which will force the plant to bend towards the light therefore affecting the height of the

The green pigment involved in photosynthesis is chlorophyll. Chlorophyll is green in appearance because it absorbs red and blue light, making these colours unable to be seen. It is the reflection of the green light that reaches out eyes, giving chlorophyll a green colour. This green light that can be seen cannot be used by the plant for photosynthesis. Therefore, theoretically growth should be inhibited in the plants only exposed to green light.

They also want to preserve the water they gained so they are mostly slower growing which takes less energy therefore less food which means they do not use as much water.

Abstract: It is important to understand the consequences of elevated light on the reproductive process of kidney beans. The main objective of this research work is to determine how light affects the seed germination in plants. Through our research we concluded that the seeds that were kept in dark were more germinated than the ones that were exposed to light. On bases of p value we can say that there is a significant difference in seed germination in light and dark condition.

Introduction: Photosynthesis can be defined as a solar powered process that removes atmospheric carbon dioxide and transforms it into oxygen and carbohydrates (Harris-Haller 2014). Photosynthesis can be considered to be the most important biochemical process on Earth because it helps plants to grow its roots, leaves, and fruits, and plants serve as autotrophs which are crucial to the food chain on earth. Several factors determine the process of photosynthesis. Light is one these factors and is the main subject of this experiment. The intensity of light is a property of light that is important for photosynthesis to occur. Brighter light causes more light to touch the surface of the plant which increases the rate of photosynthesis (Speer 1997). This is why there is a tendency of higher rates of photosynthesis in climates with a lot of sunlight than areas that primarily do not get as much sunlight. Light wavelength is also a property of

Therefore, I was correct in my hypothesis that dark will have an effect on the germination of radish seeds. Also, I was very close in predicting that the seeds grown in the light will germinate twice as much as the seeds grown in the dark; the control seeds grew a little less than double the size of the experimental seeds. Ultimately, my experiment proved that light is a very important factor in the growth of any plant. However, I’ve learned that seeds grown in the dark will germinate, though slowly, as

4.) What conclusions can you draw about which color in the visible spectrum causes the most plant growth?

In my research paper, I will attempt to determine how the perception of light in phytochromes plays a role in the development of plants. Specifically, I will look at how phytochromes play a role in the growth and development of Arabidopsis thaliana. The paper will also look at how light perception plays a role in phototropism and the immune systems of a plant. Finally, my paper will explore how changing light conditions impact perception in phytochromes.

The first side of the proverbial coin is photosynthesis. Photosynthesis is an endergonic reaction, meaning that plants absorb light energy, in order to turn carbon dioxide and water into chemical energy.

Follow the steps detailed in the first experiment to test the effects of an increase in light intensity on photosynthetic rates in corn (a C4 plant).

The tobacco plant like many plants contain a cell callus. A cell callus contains somatic undifferentiated cells and can be used to differentiate into specialized tissues of the tobacco plant, or any plant used, by being induced with the addition of different types of hormones, such as cytokinin and auxin. Cytokinin and auxin are mostly used in plant tissue culture simultaneously to provoke the formation of a plantlet or callus. There is a common use of Kinetin in plant tissue culture since when added it will promote cell division to initiate shoot tissues from calluses of the plant. Kinetin is a type of cytokinin hormone. In regards to auxin related hormones, Indole-3-acetic acid (IAA) is also commonly used since it promotes the initiation of roots for the root tissue of the plant. In this

Growth and development in a plant involves multiple processes, Cell division, cell enlargement and differentiation. Plant development is from differentiation in cells, which is cells changing or splitting into other cells. The growth of plants is in the meristem tissue and found in shoots, roots and apex,

As mentioned above, the increase in the growth of hypocotyl of white radish sprout is large and most stable on red light. In addition, that on white light has no tendency and that on blue and green light are small, although larger than that on no light. This result suggests that light seems to help the gravitropism on radish, and this effect may be maximized on red light.

This data shows a strange outcome, in the hypothesis; it says that “If acid is introduced to the seed during germination, then the roots will not grow as long as the seeds that are given water”. This statement proves to be untrue, because the roots grew longer with stronger acid than weaker acid, and in some, cases, grew better with strong acid than it did in water. This may be true because of the acid growth theory. The acid growth theory states that auxins cause the elongation of stem cells by promoting wall loosening. It was determined that this wall loosening is caused by hydrogen ions. This idea and subsequent supporting data gave rise to the acid growth theory, which states that when exposed to auxins, susceptible cells excrete protons into the wall at an enhanced rate, which in turn decreases the pH in the wall. The lowered wall pH then activates the wall loosening process which is essentially doing the same thing as the auxin hormone.

One of the first plant rooting hormones found is auxin indole-3-acetic acid in the same year, Zimmerman and Wilcoxon (1935) discovered that several new synthetic auxins, among them indole-3-butyric acid also promoted rooting. It was demonstrated that auxin indole-3-butyric is very effective in promoting rooting growth in a wide variety of plants, and it is used commercially to root many plant species world-wide (Hartmann et al. 1990). Since its introduction more than 50 years ago, auxin indole-3-butyric has been the subject of hundreds of experiments and articles. Today one can still find varieties and cultivars in almost every type of plant, respond to treatment during only part of the growing season, or produce roots only in a fraction of the treated cuttings. In recent years, several attempts were made to understand the role of auxin indole-3-butyric in the rooting process in plants at the metabolic levee