All living things depend on a source of energy for their survival. These sources may vary from one species to another. For example, human’s and animal’s main source of energy is food, while plants main source of energy is sunlight. Plants lack the ability to move and look for sources of energy, runaway from predators, or avoid Abiotic stress. Instead, they have Photoreceptors such as chlorophyll found in plants’ chloroplasts which absorbs light and changes it into a cascade of electron transfer that serve as the main source of energy for plants. Moreover, different kinds of proteins regulate the plants life cycle such as phytochrome, cryptochromes, and phototropins. These proteins are mostly pigments that intercept light at different wavelengths and thus each photoreceptor is activated by different light conditions. Using their Photoreceptors, plants transform different light signals to regulate the plant’s growth, development, defense mechanisms, and stress responses. Most of the processes and mechanisms taking place in plant cells usually rely on signaling pathways. These signaling pathways depend on proteins that have different function in activating, inhibiting, or relying the signal from a protein to another. The most important proteins in these signaling pathways are kinases and phosphatases. Studies have recently shown important data that proves the interaction of these photoreceptors and some kinases and phosphatases, for example the interaction of phytochromes with PP2A phosphatases (Bissondial, 2005).
Phosphorylation and dephosphorylation can activate or deactivate a protein but changing in 3-D conformation and as a result changing the ability to interact with other proteins. Just like in Arabidopsis and other an...
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The shape of the protein chains that produce the building blocks and other structures used in life is mostly determined by weak chemical bonds that are easily broken and remade. These chains can shorten, lengthen, and change shape in response to the input or withdrawal of energy. The changes in the chains alter the shape of the protein and can also alter its function or cause it to become either active or inactive. The ATP molecule can bond to one part of a... ... middle of paper ... ...
The majority of life on Earth depends on photosynthesis for food and oxygen. Photosynthesis is the conversion of carbon dioxide and water into carbohydrates and oxygen using the sun’s light energy (Campbell, 1996). This process consists of two parts the light reactions and the Calvin cycle (Campbell, 1996). During the light reactions is when the sun’s energy is converted into ATP and NADPH, which is chemical energy (Campbell, 1996). This process occurs in the chloroplasts of plants cell. Within the chloroplasts are multiple photosynthetic pigments that absorb light from the sun (Campbell, 1996).
Plants can absorb and use light energy because they have a green pigment, chlorophyll, contained in the chloroplasts in some of their cells. Chlorophyll allows the energy in sunlight to drive chemical reactions. Chloroplasts act as a energy transducers, converting light energy into chemical energy. So as the plant has more light the chlorophyll inside the chloroplasts can react faster absorbing in more light for food and energy.
The high rate of absorbance change in blue light in the chloroplast samples (Figure 1) can be attributed to its short wavelength that provides a high potential energy. A high rate of absorbance change is also observed in red light in the chloroplast samples (Figure 1), which can be accredited to the reaction centre’s preference for a wavelength of 680nm and 700nm – both of which fall within the red light range (Halliwell, 1984). Green light showed low rates of photosynthetic activity and difference in change in absorbance at 605nm in the chloroplast samples (Figure 1) as it is only weakly absorbed by pigments, and is mostly reflected. The percentage of absorption of blue or red light by plant leaves is about 90%, in comparison to the 70–80% absorbance in green light (Terashima et al, 2009). Yet despite the high absorbance and photosynthetic activity of blue light, hypocotyl elongation was suppressed and biomass production was induced (Johkan et al, 2012), which is caused by the absorption of blue light by the accessory pigments that do not transfer the absorbed energy efficiently to the chlorophyll, instead direction some of the energy to other pathways. On the other hand, all of the red light is absorbed by chlorophyll and used efficiently, thus inducing hypocotyl elongation and the expansion in leaf area (Johkan et al, 2012).
1. In response to light, phytochrome undergoes a change in shape that leads to the activation of
photosynthesis. This is because of the temperature around the plant. raises the enzymes controlling photosynthesis inside the chloroplasts. heat up and start moving around faster, the fast moving molecules. collide with other fast-moving enzymes, causing them to react.
The green pigment in the chloroplasts are called chlorophyll and that is what absorbs light for a process called photosynthesis. Photosynthesis is a process to make “plant food” and it takes place in the chloroplasts. The process needs sunlight, water, oxygen and carbon dioxide to create sugar. The food created in photosynthesis helps the plant grow and survive, without it, the plant would not have energy or food to do simple tasks. Furthermore, the plant takes less oxygen and releases more oxygen during photosynthesis. In addition, like I said earlier chloroplasts have chlorophyll in them and the chlorophyll gives the plant the unique green color. To summarize, the chloroplasts are vital to plants because they create food from a process called
"The Species of the Secondary Protein Structure. Virtual Chembook - Elmhurst College. Retrieved July 25, 2008, from http://www.cd http://www.elmhurst.edu/chm/vchembook/566secprotein.html Silk Road Foundation. n.d. - n.d. - n.d.
Photosynthetic pigments are essential for life because they allow photosynthesis to occur by capturing sunlight which is then used alongside carbon dioxide and water to form organic compounds such as glucose and oxygen. The pigments allow the conversion of light energy to chemical energy which other organisms can benefit from. Oxygen is utilised by other organisms in aerobic respiration. The different pigments present in the chloroplasts allow a wide variety of wavelengths of light to be absorbed for efficient photosynthesis and provide colours to the plant to attract pollinators.
Distinct characteristics are not only an end result of the DNA sequence but also of the cell’s internal system of expression orchestrated by different proteins and RNAs present at a given time. DNA encodes for many possible characteristics, but different types of RNA aided by specialized proteins sometimes with external signals express the needed genes. Control of gene expression is of vital importance for an eukaryote’s survival such as the ability of switching genes on/off in accordance with the changes in the environment (Campbell and Reece, 2008). Of a cell’s entire genome, only 15% will be expressed, and in multicellular organisms the genes active will vary according to their specialization. (Fletcher, Ivor & Winter, 2007).
Photosynthesis is a process in plants that converts light energy into chemical energy, which is stored in bonds of sugar. The process occurs in the chloroplasts, using chlorophyll. Photosynthesis takes place in green leaves. Glucose is made from the raw materials, carbon dioxide, water, light energy and oxygen is given off as a waste product. In these light-dependent reactions, energy is used to split electrons from suitable substances such as water, producing oxygen. In plants, sugars are produced by a later sequence of light-independent reactions called th...
Photosynthesis is a process in which plants and other organisms convert the light energy from the sun or any other source into chemical energy that can be released to fuel an organism’s activities. During this reaction, carbon dioxide and water are converted into glucose and oxygen. This process takes place in leaf cells which contain chloroplasts and the reaction requires light energy from the sun, which is absorbed by a green substance called chlorophyll. The plants absorb the water through their roots from the earth and carbon dioxide through their leaves.
This pigment helps mediate a chemical process called photosynthesis. This converts light energy into the chemical bond energy of carbohydrate, which is utilized as cellular energy, plant growth and development. Water, carbon dioxide, nutrients and minerals are also needed for survival. In wetlands, where stagnant water contains acidic compounds and chemicals from decaying organic matter, many plants have a difficult time obtaining necessary nutrients. It is in these nutrient poor conditions that some plants evolved different ways of obtaining nutrients.
Photosynthesis is the process in which living cells from plants and other organisms use sunlight to produce nutrients from carbon dioxide and water, the image below “Diagram of photosynthesis 1,” helps show this process. Photosynthesise generally creates oxygen as a by-product through the use of the green pigment, chlorophyll, found in the plant that helps this reaction occur. “Photosynthesis provides us with most of the oxygen we need in order to breathe. We, in turn, exhale the carbon dioxide needed by plants,” (factmonster,2017). This is able to show us why photosynthesis is so greatly needed to occur through plants in order to give one another essentials needed for continuity of life. “Plants perform photosynthesis because it generates the food and energy they need for growth and cellular respiration,” (photosynthesieeducation, 2016).
In recent years it has become clear that some environmental chemicals can cause risks to the developing embryo and fetus. Evaluating the developmental toxicity of environmental chemicals is now a prominent public health concern. The suspected association between TCE and congenital cardiac malformations warrants special attention because TCE is a common drinking water contaminant that is detected in water supplies throughout the U.S. and the world. There is a lot of concern about the clean up of toxic pollutants from the environment.