«Cells need energy to do work to carry out metabolic processes that keep them alive and functioning. This energy is stored in the form of ATP, which stands for adenosine triphosphate. All plant and animal cells use a process known as cellular...» Document abstract
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SummaryCells need energy to do work to carry out metabolic processes that keep them alive and functioning. This energy is stored in the form of ATP, which stands for adenosine triphosphate. All plant and animal cells use a process known as cellular respiration to make ATP from carbohydrates. Plant cells also have a process known as photosynthesis that they use to fixate carbon into carbohydrates using energy from the sun. However, even in plant cells, the most important energy contribution is made by cellular respiration, since ATP formed during photosynthesis is used primarily to fixate the carbon atoms for later use in glycolysis (a step of cellular respiration). Cellular respiration can either be carried out aerobically (in the presence of oxygen) or anaerobically (in the absence of oxygen) (Miyazaki, 85). This lab is concerned with testing the anaerobic pathway, namely alcohol fermentation.
Table of Contents- Alcohol fermentation occurs after glycolysis, instead of the Krebs cycle.
- The first experiment involved setting up a standard protocol, so that we could become familiar with the apparatus that measures the water displacement by CO2 and simultaneously see the affect of yeast concentration on fermentation rate.
- Following the conclusion of the standard protocol, we set up another experiment using the same set up.
- With respect to the standard protocol experiment, there is one main reason why the data turned out as it did.
- In conclusion, according to our experiment, fermentation is greatly affected by yeast concentration and pH levels.
«Bears are one of the most widely distributed animals in the world. At least one of the eight bear species currently exists in Asia, Europe, North and South America, and the Arctic. Bears in Africa became extinct several million years ago. Australia...» Document abstract
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SummaryBears are one of the most widely distributed animals in the world. At least one of the eight bear species currently exists in Asia, Europe, North and South America, and the Arctic. Bears in Africa became extinct several million years ago. Australia and Antarctica are the only continents where bears have never existed. The koala bear of Australia is a marsupial and not a true bear.
Bears also occupy a wide variety of habitats, including tropical forests, polar ice sheets, swamps, barren ground tundra, bamboo jungles, alpine meadows, and coniferous and deciduous forests. Their range extends from sea level up to about 6100 m (20,000 feet).
Bears also occupy a wide variety of habitats, including tropical forests, polar ice sheets, swamps, barren ground tundra, bamboo jungles, alpine meadows, and coniferous and deciduous forests. Their range extends from sea level up to about 6100 m (20,000 feet).
Table of Contents- Bears are one of the most widely distributed animals in the world.
- The image of bears as "man-eaters" ignites our fear of them. Human injury and deaths from natural phenomena,
- NORTH AMERICAN BEARS
- Grizzly bears
- Black Bears
- Polar Bears
- Discussion:
«Penicillin, derived from the soil mold Penicillium, was the primary antibiotic used to cure bacterial infections after being discovered in 1928 by Alexander Fleming. Briefly following its discovery and mass production bacteria began expressing...» Document abstract
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13/11/2007
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SummaryPenicillin, derived from the soil mold Penicillium, was the primary antibiotic used to cure bacterial infections after being discovered in 1928 by Alexander Fleming. Briefly following its discovery and mass production bacteria began expressing resistance to this Nobel Prize winning medical breakthrough. Bacteria causing pneumonia, toxic shock syndrome, and gonorrhea were among many of the penicillin-resistant infections that arose over time and ultimately led to death. (Lewis)
Table of Contents- Antibiotic resistance is the ability of a microorganism to become immune to an antibiotic.
- Resistance to bacteria arises most often from the transfer of plasmids.
- Materials/Methods
- Results
- Discussion
- After performing this experiment and drawing conclusions we are able to propose new questions and ideas to research and investigate.
«Plants have served as both poisons and medicines. Dioscorides listed several hundred plant species in his first Materia Medica in 78 BC. Galen, in second-century Rome, catalogued plants, including those containing opiates, ergotamines, and other...» Document abstract
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biology
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SummaryPlants have served as both poisons and medicines. Dioscorides listed several hundred plant species in his first Materia Medica in 78 BC. Galen, in second-century Rome, catalogued plants, including those containing opiates, ergotamines, and other alkaloids. Pharmacognosy was established as an independent discipline in nineteenth century Europe.
Toxic plants are ingested by curious children, by foragers mistaking poisonous plants for edible fare, by herbalists mistaking poisonous plants for nontoxic remedies, by pleasure seekers attempting to attain natural highs, and by suicidal patients attempting to harm themselves. Over 122,000 plant ingestions or exposures were reported to 65 poison control centers serving more than 257 million people in 1998. Plant exposures represented 5.5% of total toxic exposures reported in 1998 (fourth after cleaning substances, analgesics and cosmetics/personal care products). Approximately 7% of plant ingestions required treatment at a health care facility, with four deaths reported. More than 68% of all plant ingestions reported were in children under age 6 years.
Toxic plants are ingested by curious children, by foragers mistaking poisonous plants for edible fare, by herbalists mistaking poisonous plants for nontoxic remedies, by pleasure seekers attempting to attain natural highs, and by suicidal patients attempting to harm themselves. Over 122,000 plant ingestions or exposures were reported to 65 poison control centers serving more than 257 million people in 1998. Plant exposures represented 5.5% of total toxic exposures reported in 1998 (fourth after cleaning substances, analgesics and cosmetics/personal care products). Approximately 7% of plant ingestions required treatment at a health care facility, with four deaths reported. More than 68% of all plant ingestions reported were in children under age 6 years.
Table of Contents«Mushrooms are often considered the vermin of the vegetable world, likened to snakes, slugs, and worms. Some are regarded as mystical and others as delicacies. The location of tasty morels is passed from generation to generation, closely guarded from...» Document abstract
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biology
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13/11/2007
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SummaryMushrooms are often considered the vermin of the vegetable world, likened to snakes, slugs, and worms. Some are regarded as mystical and others as delicacies. The location of tasty morels is passed from generation to generation, closely guarded from strangers. Each autumn and spring, foragers scour the woods for known delicacies, and new ones untried. Some mushroom foragers search for "little brown mushrooms," not for their taste, but to evoke hallucinations.
Table of Contents- Eating unidentified or misidentified species can be dangerous. Each year there are 10,000 to 15,000 cases of mushroom toxicity in the United States.
- As a mushroom emerges from the ground, it is covered with a membrane or veil.
- The stalk (stipe) begins at the cap and ends either underground or in a cup (vulva).
- The most common commercially available mushroom in the United States is Agaricus bisporus.
- GI symptoms after ingestion of mushrooms may not be caused by toxins.
- Victims with GI symptoms can be divided into those with early and those with delayed presentations.
- Any person with unexplained acute renal failure should be questioned about prior wild mushroom ingestion.
«The phylum Arthropoda contains about four fifths of the known animals of the world, and insects are the largest group of arthropods. Insects are an important part of the biota of all terrestrial and freshwater environments that support life; only in...» Document abstract
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biology
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19/11/2007
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SummaryThe phylum Arthropoda contains about four fifths of the known animals of the world, and insects are the largest group of arthropods. Insects are an important part of the biota of all terrestrial and freshwater environments that support life; only in marine environments are they relatively unimportant. More species of insects exist than of any other form of multicellular life, and they may well exceed all other land animals in biomass. Insects can use most animal and plant substances as food, and their feeding plays a vital role in recycling organic compounds. They compete with other organisms for the world's food supplies but are themselves a major food source for many forms of life. They are essential for the pollination of many plants. Insect life cycles are diverse and often complex, involving developmental and sexual stages that are widely different in morphology and ways of life. Although sexual reproduction is the rule, parthenogenesis (unisexual reproduction) and pedogenesis occur. Some groups, such as ants, bees, and termites, have developed a high degree of social organization. During at least part of its life cycle, an insect's body is divided into three distinct regions (head, thorax, and abdomen), with three pairs of legs attached to the thorax. Except for a few primitive or parasitic groups, most adult insects have wings.
Table of Contents- The greatest direct medical importance of insects is associated with their feeding on human blood and tissue fluids.
- In the eastern United States, blister beetle dermatitis is usually caused by Epicauta species, which occur on many garden plants.
- Patients with delusions of parasitosis are convinced, against all evidence to the contrary, that parasites infest their skin and often their homes and clothing.
- Many patients with parasitophobia know that their fear is groundless but are still unable to overcome it.
«North America is unique in that it is home not only to venomous snakes, but also to the world's only known venomous lizards. Fortunately, bites by venomous reptiles in North America are relatively uncommon, although precise statistics are not...» Document abstract
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19/11/2007
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SummaryNorth America is unique in that it is home not only to venomous snakes, but also to the world's only known venomous lizards. Fortunately, bites by venomous reptiles in North America are relatively uncommon, although precise statistics are not available. The only systematic attempt to evaluate the incidence of venomous snakebite in the United States was done in the late 1960s by Dr. Henry Parrish. He estimated that there were approximately 7000 bites by venomous snakes, of which approximately 15 ended in death. The incidence of venomous snakebite may have changed significantly since Parrish's study, but given that snakebite is not a reportable "disease," no mechanism exists for obtaining reliable data. The incidence of snakebite in Canada is lower than that in the United States because fewer snakes species are found farther north up the continent. In Mexico, however, snakebite takes on increasing medical importance because this country has more venomous snake species than any other nation in the New World. As many as 150 deaths may be caused by snakebite in Mexico each year.
Table of Contents- Establishing credible estimates of the incidence of venomous lizard bites is even more difficult than for snakes
- Snake venoms are highly complex mixtures of enzymes, low-molecular-weight polypeptides, glycoproteins, minerals, and other unidentified substances.
- Rattlesnakes are the most widespread of pit vipers, found throughout most of North America.
- The only two known species of venomous lizards in the world are found in North America and belong to the genus Heloderma.
- With the growing popularity of herpetoculture in the United States, bites by captive venomous reptiles have increased.
«Scorpion envenomation can result in distinct clinical syndromes. Most scorpion species' stings cause only local pain and inflammation that respond well to minimal supportive therapy and wound care. These scorpions pose no significant management...» Document abstract
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biology
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SummaryScorpion envenomation can result in distinct clinical syndromes. Most scorpion species' stings cause only local pain and inflammation that respond well to minimal supportive therapy and wound care. These scorpions pose no significant management issues and, with few exceptions, are not discussed here in further detail. The truly dangerous scorpions of the world, typified by Tityus species in the Caribbean region and in South America, Androctonus species and Buthus occitanus in North Africa, Leiurus quinquestriatus in the Near East, and Mesobuthus tamulus in India, cause an "autonomic storm" with prominent cardiopulmonary effects. A third clinical syndrome occurs from stings of Centruroides species in the southwestern United States and Mexico and from Parabuthus species in southern Africa. These produce prominent neurologic effects associated with excess cholinergic tone. Children are typically more severely affected than adults and often require prompt medical management to avoid morbidity and mortality. The ideal treatment of scorpion envenomation remains controversial, primarily because controlled clinical trials are lacking. Although anecdotal experience and comparisons of historic cohorts demonstrate a benefit from aggressive symptomatic and supportive care, the proper use of antivenins has not been fully resolved.
Table of Contents- INTRODUCTION
- TAXONOMY AND ANATOMY
- VENOM
- PREVENTION
«Insects of the order Diptera are characterized by one pair of wings. The second pair is usually modified to form a pair of drumsticklike structures known as halteres. A typical life cycle consists of eggs, limbless larvae, pupae, and winged adults,...» Document abstract
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SummaryInsects of the order Diptera are characterized by one pair of wings. The second pair is usually modified to form a pair of drumsticklike structures known as halteres. A typical life cycle consists of eggs, limbless larvae, pupae, and winged adults, but numerous variations exist. Mouthparts are of the sucking type. Females of many species, although free living, take blood or other tissue fluids from vertebrates, injecting salivary secretions that are not intrinsically toxic but are potent sensitizing agents for most humans. Larvae of some Diptera are human parasites. Other adult Diptera feed indiscriminately on feces and human foodstuffs. These habits make them by far the most important arthropod vectors of human disease.
Table of Contents- Most of these insects are cosmopolitan in distribution, except tsetse flies, which are restricted to Africa, and tropical and subtropical sand flies.
- Carbon dioxide, body heat, and sweat gland secretions, especially apocrine, are attractants for mosquitoes; certain skin lipids are repellent.
- Treatment of mosquito bites consists of local application of antipruritic lotions or creams.
- Bites are immediately painful and result in raised, red, and pruritic lesions that persist from a few hours to a week or more.
- Blackfly bites are more common on the upper half of the body.
- Horseflies and deerflies are medium to large (10 to 25 mm body length) stocky flies whose large eyes often are brightly colored.
- The term myiasis for parasitism by fly larvae was introduced into the medical literature in 1840, although the condition has been observed since antiquity.
- Another form of migratory myiasis is caused by larvae of Gastrophilus, which normally are gastrointestinal or nasal parasites of horses.
«Insects of the order Lepidoptera typically cause human envenomation, but effects generally are less serious than with hymenopterans. Injury usually follows contact with caterpillars, occurring less frequently with the cocoon or adult stage. The...» Document abstract
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SummaryInsects of the order Lepidoptera typically cause human envenomation, but effects generally are less serious than with hymenopterans. Injury usually follows contact with caterpillars, occurring less frequently with the cocoon or adult stage. The larval lepidopteran (caterpillar) is usually free living, is moderately active, and feeds on plants, although a few are parasites of insect nests or eat food of animal origin. The pupal stage may be free or encased in a silk cocoon. Wintering over in cold climates is usually in the pupal stage. Adults (butterflies and moths) have wings with microscopic chitinous scales. They primarily feed on nectar and other plant juices, but some eat semiliquid mammalian feces and urine. The adult provides no care or protection of immature stages. No social organization exists, although larvae and adults of some species assemble in large aggregations.
Table of Contents- Venomous species occur in about 16 families of Lepidoptera, with no general rules for recognition.
- This hairy, flat, and ovoid caterpillar reaches a length of 30 to 35 mm and feeds on shade trees, including elm, oak, and sycamore.
- Caterpillar envenomation usually occurs when living insects are touched as they cling to vegetation or drop onto bare skin.
- The second syndrome is associated with caterpillars with a less highly developed venom apparatus (e.g., Lymantria, Euproctis, Thaumetopoea).
- Trees on which caterpillars feed may be sprayed with appropriate insecticides to control species such as the puss caterpillar.
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