VIBS 422- Exam 1 Questions and Answers Solved 100%

VIBS 422- Exam 1 Questions and Answers Solved 100% 4 ancient civilizations - Answers - Ancient Egypt (Nile river) - Babylon Mesopotamia (Euphrates-Tigris) - Ancient India (River Sindh) - China (yellow River) who is the author of the book "The Third Wave"? - Answers Alvin Toffler the "Industrial Revolution" began in which country? - Answers Britain What were the 3 "waves"? - Answers 1st- agricultural revolution 2nd- industrial revolution 3rd- information technology What are the major consequences of deforestation? - Answers Increased CO2, decreased O2, and global warming Since the industrial revolution, atmospheric carbon dioxide concentrations have risen by _____% to the highest level? - Answers 37% What are the 3 major routes of pollution? - Answers Air pollution, land pollution, and water pollution what is the cause of acid rain? - Answers Sulfur dioxide polluting the air. It is released into the atmosphere by burning sulfur containing compounds (e.g. sulfuric acid, sulfate, and nitrate salts). What happened in Hinkley, CA? - Answers - there was arsenic and uranium in the aquifers drinking water. - caused skin and stomach cancer, tumors, and other illnesses and death what are the two different groups of factors contributing to water pollution? - Answers point sources and non point sources What are point sources? - Answers -Water pollution sources that can be controlled or reduced. They are easier to stop. -examples: waste products from factories, sewage systems, oil wells, power plants What are non point sources? - Answers - Water pollution sources that are difficult to control or reduce. -Examples: runoff fertilizers from farm land, parking lots/streets, air pollutants getting washed to earth, storm water drainage from lawns/parking lots/streets Significance of the water contamination in the great lakes - Answers - the great lakes are contaminated with PCBs - therefore, the fish are also contaminated - local residents eating the fish have higher amounts of PCBs in their bodies and thus experience many related health effects Explain the importance of the Flint water chrisis - Answers - Flint river was contaminated with lead (a heavy metal neurotoxin) and created a serious public health danger - the water was treated improperly and this caused the lead from aging pipes to leach into the water supply - 6,000-12,000 children have been exposed Define EDCs. - Answers Endocrine Disrupting chemicals are man-made, synthetic chemicals and natural phytoestrogens that act on the endocrine systems of humans and animals by mimicking, blocking, and/or interfering in some manner with the natural instructions of hormones to cells. Briefly describe the key mechanisms of EDCs. - Answers Mimicking the effects of natural hormones by recognizing their binding sites (receptors). - antagonizing the effects of these hormones by blocking their interaction with their physiological binding sites - reacting directly and indirectly with the hormone in question - altering the natural pattern of synthesis of hormones - altering hormone receptor levels Name any 3 EDCs that are highly predominant in day to day life - Answers - Herbicides (Ex. Atrazine) - Insecticides (Ex. DDT and metabolites) - Industrial chemicals (Ex. Dioxins, phthalates, styrenes) - Tobacco smoke - hormones - pesticides - pharmaceuticals - industrial by-products - antibacterials - personal care products and medical tubing - childrens products What is the drawback in producing GM crops? - Answers Pesticides can damage crops and poison birds, animals, and fish. Most pesticides kill or damage life forms other than those intended. what part of the body has maximal absorption of PBCs? - Answers - the head (4x more absorbent) - the genital area (11x more absorbent) Name 2 naturally occuring EDCs. - Answers Phytoestrogens and fungal estrogens What effect has DDT had on eagles? - Answers - Eggshell thinning - decreased reproduction why are children more susceptible to EDCs? - Answers - absorb more pesticides from their environment than adults (play close to ground, touch eyes/mouth/nose) - they are less able to detoxify and excrete pesticides because of their less developed immune system - all children are exposed to toxic synthetic chemicals before birth and continue to be exposed for the rest of their lives Explain endocrine, paracrine, autocrine, and neurocrine hormones. - Answers - Endocrine = acts as a site distant from the secreting cell/gland - Paracrine = acts on a cell near the secreting cell - Autocrine = acts on secreting cell - Neurocrine = secreted by neural cells (Ex. Neurotransmitters and neurohormones) Describe peptide hormone signaling. - Answers 1. the hormone binds to a site on the extracellular portion of the receptor 2. The receptors are seven transmembrane proteins that pass through the plasma membrane 7 times 3. N-terminal exposed at the exterior of the cell and C terminal projecting into the cytoplasm 4. Binding of the hormone to the receptor activates a G protein 5. This initiates the production of a "second messenger" which is produced by adenylyl cyclase 6. The second messenger initiates a series of intracellular events such as phosphorylation and activation of enzymes; release of Ca2+ into the cytosol from stores within the ER 7. These enzymatic changes activate the transcription factor CREB Describe steroid hormone signaling. - Answers -Made from cholesterol, are lipophilic and can enter target cell -Immediately released from cell after synthesis -Interact with cytoplasmic or nuclear receptors -Activate DNA for protein synthesis -Are slower acting and have longer half life than peptide hormones Action: 1. Most hydrophobic steroids are boind to plasma protein carriers. Only unbound hormones can diffuse into the target cell 2. Steroid hormone receptors are in the cytoplasm or nucleus 3. The receptor hormone complex binds to DNA and activates or represses one or more genes 4. Activated genes create new MRNA that moves back to the cytoplasm 5. Translation produces new proteins for cell processes 6. Some steroid hormones also bind to membrane receptors that use second messenger systems to create rapid cellular responses What are endocrine disruptors? - Answers Endocrine disruptors are man made synthetic chemicals and natural phytoestrogens that act on the endocrine system of humans and animals by mimicking, blocking, and or interfering in some manner with the natural instructions of hormones to cells Explain bioaccumulation of EDCs in the food chain - Answers Bioaccumulation- toxicants build up in animal tissues - being at the top of the food chain, humans have some of the highest EDC concentrations explain the reason why breast milk is often high in EDCs - Answers Dioxin is stored in the mothers fat explain the reason why adipose tissue is often high in EDCs - Answers EDCs are fat soluble describe PVC use in day to day life - Answers high amounts in plastics - used in residential and municipal water pipes, toys, food wrap, clothing, raincoats, shoes, building products, and medical equipment explain briefly the modes of exposure to dioxins and its health impact - Answers -Produced when heating our food in the microwave using plastic containers -High heat and plastics release dioxins into the food and ultimately into the cells of the body -Dioxins are carcinogens and highly toxic to the cells of our bodies -Half life in humans is 8.5 years how are women and children at greater risk for phthalate exposure? - Answers phthalates are present in children's toys and many cosmetics as "added fragrance" what is DES (diethylstilbestrol) and how does it affect women's reproductive health? - Answers DES is a synthetic estrogen used to prevent miscarriages. - found to be a teratogen when given to pregnant women Explain the impact polystyrene use in fast food has had on human health - Answers Polystyrene is made into food containers. Styrene monomer leaches in hot and cold water. For these reasons, many cities have banned the use of polystyrene by fast food vendors. Describe the persisting problem with DDT - Answers - used as a pesticide - causes congenital malformation in wild animals - results in a decline of sperm counts in men - increases breast cancer in women What is atrazine and how does it affect wildlife? - Answers atrazine is a widely used agricultural herbicide for control of broad leaf and grassy weeds, predominantly for weed control in corn and soybean crops list a few rules to avoid/minimize exposure to EDCs. - Answers - eat fewer animal products - stop microwaving food in plastic containers - get rid of old paint carefully - get a good water filter - eat fresh produce instead of canned - buy organic produce - avoid products that list "added fragrance" -get enough iodine Why does PCB make such a good thyroid hormone disruptor? - Answers similar structure Name a few classes of EDCs - Answers - Heavy metals - combustion by-products - pharmaceuticals - pesticides - plasticizers - plastic monomers - flame retardants - detergents/surfactants - persistent organochlorines what was the purpose of the books "Silent Spring" and "Our stolen future"? - Answers bring attention to the effects of chemical pollution and endocrine disruptors in wildlife List 3 EDCs and their effects on a specific animal. - Answers - European otter- PCBs cause reproductive impairment - Peregrine falcon- DDE causes egg shell thinning - american alligator- DDE causes low hatching rates and abnormalities in males and females - panther- Hg, DDE, and PCBs cause cryptorchidism how does structure and chlorination affect PCB toxicity? - Answers The more chlorines the more toxic Explain the synergistic effect. - Answers The combination of more than one chemical can increase the toxicity many more times above that of each chemical separately. (Ex. roundup (herbicide) and glyphosate (a herbicide that kills weeds) Mention 3 EDCs associated with ASD and ADHD. - Answers Lead, methylmercury, BPA, PCBs, dioxins, and pesticides