Lab 4 Quiz Bank Questions
- How are petroleum deposits formed from the bodies of photosynthetic organisms?
- How is nylon made from petroleum products?
- Is there anything man-made that does not depend on the products of photosynthesis for its production? What on earth (man-made or otherwise) does not depend on photosynthesis?
- Why do some plants have red leaves, and what purpose is this hypothesized to serve?
- How did the FIRST photosynthetic organism come into existence?
- Has the process of photosynthesis evolved over time? How?
- How does red tide occur, and what about these organisms makes red tide toxic to people?
- Can you differentiate among plants based on only their chloroplasts?
- How does uv light affect photosynthesis? Are there plants that can use uv light for the light reactions of photosynthesis?
- Do pesticides affect reaction rates (specifically of photosynthesis)?
How does red tide occur, and what about these organisms makes red tide toxic to people?
ReplyDeleteRed tide blooms contain brevetoxins. This organism is fragile, so when a wave crashes on the shoreline, it is easily broken open and its toxins are released. Brevetoxins are lipid soluble, making it easy for them to pass through cell membranes, including the skin. They also ionically depolarize nerve cells by opening gated sodium channels, which leads to respiratory and cardiac malfunctions.
Brevetoxins are dangerous to marine life because the organism stops muscle coordination, paralysis, and the respiratory system. Red tide can kill up to 100 tons of fish per day. Because brevetoxin can easily travel through the air, people on the shore can inhale the organism. Inhalation of the toxin affects the respiratory system and can cause bronchoconstriction, as well as irritation of the eye. As a remedy, the patient should immediately seek an air-conditioned environment. If a person consumes an oyster infected by red tide blooms, the effect is neurotoxic shellfish poisoning (NSP), which has gastrointestinal symptoms and some neurologic symptoms.
Kirkpatrick, B. (2004). Literature review of Florida red tide: implications for human health effects. Harmful Algae, 3(2), 99-115. doi:10.1016/j.hal.2003.08.005
-Michelle Corrado
Why do some plants have red leaves, and what purpose is this hypothesized to serve?
ReplyDeleteAnthocyanins are responsible for giving plants a red/purple/blue color. Red-leafed flora is present in every plant species, whether at a particular stage or for its entire life. There are several reasons why being red can be an advantage. Some animals lack red light receptors, which serves as protection for the plant (and sometimes its fruit). Also, some insects see red and think that the leaves are inedible. Leaves rich in chlorophyll and anthocyanins appear brown or black, serving as camouflage against dead foliage and soil. Sometimes leaves receive more light than is needed for photosynthesis which can damage DNA, denature proteins, and have other harmful effects, so the anthocyanins help to reduce the severity of photosynthesis and advance photosynthetic recovery. A study exposed a red and acyanic leaf to a 30-minute white light. In this time frame, photosynthesis was reduced only 60% in the former but 100%in the latter; red leaves recovered after 80 minutes, whereas the acyanic took hours. Red leaves may also serve as a sunscreen for the plant, protecting it from UV-B radiation.
Gould, K. S. (2004). Nature’s Swiss Army Knife: The Diverse Protective Roles of Anthocyanins in Leaves. Journal of Biomedicine and Biotechnology, 2004(5), 314-320. doi: 10.1155/S1110724304406147
-Michelle Corrado
How is nylon made from petroleum products?
ReplyDeleteNylon, a synthetic man made fiber, is made in a rather complex way. In order for the nylon to be fabricated, chemicals extracted from crude petroleum, water and air collectively must be polymerized and treated to make the molecule change in shape. Lengthening of the molecule is seen. By heating the substance at a considerably high temperature allows these molecules to undergo further changes and remove excess water (hydrolysis). These monomers join. As it cools, the fiber is to be manufactured to creates a threadlike fiber. Although it is may appear thin, it is very tough.
National Research Council, Fibers as Renewable Resources for Industrial Materials. National Academy of Sciences, 1996. Print.
How does uv light affect photosynthesis? Are there plants that can use uv light for the light reactions of photosynthesis?
ReplyDeleteUV light can indeed affect photosynthesis whether it is beneficial or pose as a threat. Plants use sun as a source of light, because the sun emits UV lights, the plants must inevitably deal with the effects of UV lights. UV-B, a radiation emitted by sun has proven to show a positive correlation to plant’s sensitivity in growth and photosynthetic capacity. A considerable amount of plants tested with UV-blue radiations have shown a negative response with respect to the amount of UV-B radiations. UV-B radiations affect the overall photosynthesis process by damaging the Photosystem II and Rubsico of the plant. By damaging the photosystem II, Rubsico and functions from the stomata will lower hence the plant’s photosynthesis activity. In order to regulate growth, instead of using chemical growth regulators, few agricultural workers have exposed the plant to UV-b light. Some plant’s response to the exposure to UV-B radiations has shown changes of the structure of leaves. Some plants respond to UV light with any sort of correlation as oppose to others that don’t show any correlation.
Michelle Hwang
Teramura, Alan. (1991). Changes in growth and photosynthetic capacity of rice with increased UV-B radiation. Physiologia Plantarum. 83(3):373-380.
Do pesticides affect reaction rates (specifically of photosynthesis)?
ReplyDeletePesticides are chemicals designed to destroy or repel insects, other bugs, plant diseases, weeds, and other pests. They work because they are toxins. Pesticides have been shown to inhibit the rate of photosynthesis in multiple plant species. The exact degree and duration of this inhibition varies depending on the type of pesticide used, the species of plant, and the plant or seedling age. Each pesticide affects different functions of the plant. Many restrict stomatal openings, thereby inhibiting CO2 intake, which is a fundamental factor in photosynthesis. Others do so by causing damage to photosystem II in the chlorophyll or by inhibiting necessary enzymes. Some plants exhibit large reductions in photosynthesis while others only show small decreases. Due to the range of reactions in different plant species from different pesticides, it is too difficult to make a generalization concerning overall pesticide effect on plants and duration of the effects. However, some degree of photosynthetic inhibition is seen in the majority of cases.
Jones,V. P., Youngman, R. R., and Parrella, M. P. (1983). Effect of Selected Acaricides on Photosynthetic Rates of Lemon and Orange Leaves in California. Journal of Economic Entomology, 76(5), 1178-1180. Retrieved from http://entomology.tfrec.wsu.edu/VPJ_Lab/downloads/71.pdf.
Xia, X. J., Huang, Y. Y., Wang, L., Huang, L. F., Yu, Y. L., Zhou, Y. H., and Yu, J. Q. (2006). Pesticides-induced depression of photosynthesis was alleviated by 24-epibrassinolide pretreatment in Cucumis sativus L. Pesticide Biochemistry and Physiology, 86(1), 42 – 48. DOI: 10.1016/j.pestbp.2006.01.005.
--Dallas Joiner
How are petroleum deposits formed from the bodies of photosynthetic organisms?
ReplyDeletePetroleum was formed from the remains of tiny sea organisms and some land organisms that were washed into the sea. One of the most likely contributors are diatoms, which are tiny, single-celled phytoplankton dating back almost to the formation of earth 3.5 billion years. The formation of crude oil from these diatoms probably millions of years ago as these and other organisms accumulated in the bottoms of lakes, seas, and rivers. Buildup of this organic matter over time increased the pressure of each layer below by thousands of times and increased the temperature hundreds of degrees. Over millions of years, these high temperatures and pressures removed oxygen in the form of water and carbon dioxide, transforming the leftover organic matter (termed “kerogen”) into crude oil. Crude oil, therefore, is mainly made up of hydrocarbons. If this oil is pushed deeper into the sediment, increasing temperatures above 150 °F will arise, transforming crude oil into natural gas. Further heating forms methane. Oil reservoirs form the upflow of oil towards the surface due to oil’s lower density than that of the Earth’s crust.
The origin and chemistry of petroleum. (2006). DPRA. Retrieved from http://www.dpra.com/index.cfm/m/158.
Petroleum. Microsoft Encarta Online Encyclopedia. (2009). Retrieved from http://encarta.msn.com.
-Dallas Joiner