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17 Dec 2007
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Results and Figures of Salt on Germination and Growth

Essay - 3 pages - Biology

Finding the effects of salt on germination and growth of plants took twenty-two days of research. Each collection day the height, height of the leaf, color, height of the node, number of buds, and the number of the flowers were taken into account. Based on the original hypothesis stating that the...

17 Dec 2007
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Brassica Rapa in Comparison With Sodium Chloride

Essay - 4 pages - Biology

In this study the Brassica Rapa will be tested to see if salt water effects it's growth. Data will be taken from four different types of groups: distilled water; 0.25% of sodium chloride; 1.00% of sodium chloride; and 4.00% of sodium chloride. Data will be collected in a twenty-two day span,...

27 Nov 2007
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The Social History of LSD

Essay - 4 pages - Biology

When Albert Hofmann created LSD 25 during experimentation in his laboratory, he had no idea what was to become of it, or what kind of an impact it would have. "Dr. Humphry Osmond invented the term 'psychodelic', which was later amended to 'psychedelic to get rid of the nuthouse...

27 Nov 2007
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The CCR5-Delta 32 Genetic Mutation and Human Evolution - published: 27/11/2007

Essay - 2 pages - Biology

Genetic mutations are not uncommon. They can happen for a variety of reasons and have a variety of effects. Those with negative effects are weeded out by natural selection, and those with positive effects prevail and are accumulated due to natural selection. These...

26 Nov 2007
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Venomous Lizards

Essay - 2 pages - Biology

The two venomous lizards of the world are impressive creatures about which much misinformation has been spread for centuries. They have been thought to possess supernatural features such as poisonous breath, a stinging tail and the ability to spit their venom. The Gila monster (Heloderma...

26 Nov 2007
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Venomous Snakes

Tutorials/exercises - 4 pages - Biology

The term pit viper comes from the presence of paired, highly sensitive, thermoreceptor organs (pits) present on the forward portion of these snakes' heads. These structures, also known as foveal organs, serve the snake in locating prey, aiming strikes, and adjusting venom dose. The foveal...

26 Nov 2007
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An Assessment of Historical and Contemporary Land Use at Hedgehog Mountain, Freeport, Maine, via Field Observation

Case study - 5 pages - Biology

The purpose of this investigation was to collect information that allowed the formulation of a hypothesis as to the land-use history of the Hedgehog Mountain preserve, and to correlate empirical observations with a limited literature review in an attempt to validate the hypothesis presented....

26 Nov 2007
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Intraneuronal Signaling Pathways

Tutorials/exercises - 7 pages - Biology

Prior to delineating the organization of specific intraneuronal signaling pathways, it is important to consider, in general terms, their role in helping neurons interpret and respond to the barrage of afferent stimulation impinging on them continuously. From an evolutionary perspective, second...

26 Nov 2007
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Ion Channels

Tutorials/exercises - 6 pages - Biology

Structure and Function of Voltage-Gated Ion Channels Voltage-gated ion channels allow the flow of ions in response to changes in membrane voltage and are key elements in neuronal excitation and inhibition. Although ion channels can usually pass more than a single type of ion, voltage-gated...

26 Nov 2007
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Neurotransmitter and Ion Channels

Tutorials/exercises - 3 pages - Biology

Classes of Neurotransmitters Much of the information transfer between neurons in the CNS occurs via chemical synapses. These synapses use a variety of messengers (neurotransmitters) that are released in a Ca2+-dependent fashion from presynaptic terminals and act on specific protein receptors to...

26 Nov 2007
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Sybaptic Plasticity

Tutorials/exercises - 4 pages - Biology

In its simplest form, the postsynaptic response to neurotransmitter release can be mediated by a single protein complex. For example, nicotinic acetylcholine receptors are self-contained stimulus-response modules that both detect a stimulus, acetylcholine, and generate a response, passage of ion...

26 Nov 2007
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Principles of Cellular Electrophysiology

Tutorials/exercises - 3 pages - Biology

Resting Membrane Potential In nerve cells, potassium ions (K+) are at higher concentration inside the membrane than outside whereas the opposite is true for sodium (Na+), calcium (Ca2+), and chloride (Cl-) ions (Fig. 1.9-1). The bulk solutions on either side of the membrane are electrically...

26 Nov 2007
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Receptors and Second Messengers

Tutorials/exercises - 11 pages - Biology

Neuropeptide receptors have undergone the same process of discovery and characterization that receptors for other neurotransmitters have enjoyed. The process begins with the pharmacological characterization of the receptor's physicochemical binding properties by assessing the affinity of...

26 Nov 2007
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Neuropeptides: Biology and Regulation

Tutorials/exercises - 7 pages - Biology

The past several decades have witnessed a veritable explosion of knowledge about the central nervous system (CNS), and in no area has this been as impressive as in peptide neurobiology. Numerous peptide neurotransmitter candidates have been identified and characterized, their CNS...

20 Nov 2007
ppt

Pinus strobus - Eastern White Pine

Presentation - 26 pages - Biology

Common: Eastern White Pine Scientific: Pinus strobus Derivation of name: Latin name for pine from Greek "pitus" / incense-bearing or a gum-yielding tree (pitchy) or [sic] Greek "strobus" (cone) [1] Also known as: white pine, northern white pine, northern...

20 Nov 2007
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Mites

Tutorials/exercises - 4 pages - Biology

Mites make up the largest group in the class Arachnida. Most are small arthropods, and many are barely visible. Mites have two body regions, a small cephalothorax and a larger, unsegmented abdomen. The cephalothorax and abdomen are broadly joined, giving most mites an oblong to globular...

20 Nov 2007
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Lice

Tutorials/exercises - 2 pages - Biology

Lice are small wingless insects that are ectoparasites of mammals. They are mostly host specific, and two species are human parasites: Pthirus pubis (pubic louse) and Pediculus humanus, with two varieties, P. h. capitis (head louse) and P. h. corporis (body louse). They are obligatory parasites,...

20 Nov 2007
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Bees, Wasps and Ants

Thesis - 4 pages - Biology

By far the most important venomous insects are members of the order Hymenoptera, including bees, wasps, and ants. They vary in size from minute to large (up to 60 mm in body length). The abdomen and thorax are connected by a slender pedicle that may be quite long in certain wasps and ants. Bees...

20 Nov 2007
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Venomous Species and Venoms

Tutorials/exercises - 2 pages - Biology

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 larval lepidopteran (caterpillar) is usually free...

20 Nov 2007
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Diptera: Two-winged flies

Tutorials/exercises - 5 pages - Biology

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, but numerous variations exist....

19 Nov 2007
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Scorpion Envenomation

Tutorials/exercises - 2 pages - Biology

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 issues and, with few exceptions, are not...

19 Nov 2007
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North American Venomous Reptile Bites

Tutorials/exercises - 2 pages - Biology

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 available. The only systematic attempt to evaluate...

19 Nov 2007
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North American Arthropod Envenomation and Parasitism

Tutorials/exercises - 2 pages - Biology

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 marine environments are they relatively...

13 Nov 2007
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Mushroom Toxicity

Tutorials/exercises - 3 pages - Biology

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 strangers. Each autumn and spring, foragers...

13 Nov 2007
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Toxic Plant Ingestions

Tutorials/exercises - 6 pages - Biology

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 alkaloids. Pharmacognosy was established as an...

13 Nov 2007
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The Effect of Ampicillin Amounts and Incubation Time on E. Coli Growth

Tutorials/exercises - 5 pages - Biology

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 resistance to this Nobel Prize winning medical...

23 Oct 2007
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Bear Attacks

Tutorials/exercises - 5 pages - Biology

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 and Antarctica are the only continents where...

23 Oct 2007
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Fermentation Lab Report

Case study - 4 pages - Biology

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 respiration to make ATP from carbohydrates. Plant cells...

09 Oct 2007
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ATP Production through Fermentation

Case study - 2 pages - Biology

Many people are already indirectly familiar with the processes of fermentation, from the baker to the body builder. The baker, when baking his bread, adds yeasts that produces CO2, which makes the bread rise. Alcohol is also produced during this fermentation but it quickly evaporates during the...

02 Oct 2007
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Osmolarity and Body Volume - published: 02/10/2007

Case study - 2 pages - Biology

Our bodies and many other animals' cells extracellular and intracellular fluids are mainly comprised of water with ionized salts in solution. These salts, mainly Na+, K+, Cl-, Ca2+, and Mg2+ ( Foundations Of Biology: Cell and Organ Physiology, Faculty of the Department of Neurobiology and...