... time greatly affects the impact that the pollutant will have on an ecosystem and population. Pollutants can affect both a population and an ecosystem. A pollutant on a population level can be either non-target or target. Target effects are those that can kill off the entire population. Non-target effects are those that effects a significant number of individuals and spreads over to other individuals, such is the case when crop dusters spread herbicides, insecticides. Next we look at population damage by a pollutant, which in turn has a detrimental effect on the ecosystem in several ways. First, by the killing of an entire population by a pollutant, it offsets the f ...
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... of the 555 IC, which is pin 3, goes LOW. This in turn activates and lights the top LED (the HIGH indicator). Logic probes derive their operating power from the PCB under test. Care should be taken in attaching the clips to safe voltages; you may want to first use a Volt Meter (Digital Multi Meter) to verify the hook up points have good voltages. The four diodes protect the IC from reverse polarity. Capacitor C1 prevents transient voltage from affecting the logic probe when the black lead is not connected. Pin 5 of the 555 IC is grounded through resistor R1. The logic probe will indicate a HIGH for 2V or greater, and a LOW for 0.8V or less. To use this logic p ...
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... we must first ascertain what HIV is, how the body attempts to counter the effects of viruses in general, and how HIV infects the body. Definition HIV is the virus that causes AIDS. HIV is classified as a RNA Retrovirus. A retrovirus uses RNA templates to produce DNA. For example, within the core of HIV is a double molecule of ribonucleic acid, RNA. When the virus invades a cell, this genetic material is replicated in the form of DNA . But, in order to do so, HIV must first be able to produce a particular enzyme that can construct a DNA molecule using an RNA template. This enzyme, called RNA-directed DNA polymerase, is also referred to as ...
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... joint projects with students in other cities, states and even countries (Carey 26). Studies on students who have twenty four hour access to laptops have shown that students shown an increase in problem-solving and critical thing sills, enhanced learning in core academic subjects, produce higher quality work and have even provided more one-on one time between teachers and students (THE Journal 16). Technology is an integral component of learning. Being that students learn at different rates, technology can individualize instruction. They can move at an appropriate pace providing a solid foundation of basic skills. Computer based technologies can administer i ...
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... after lobe-finned fish, and before the first fully terrestrial vertebrates. The earliest tetrapod known is Acanthostega. It is also considered the most primitive tetrapod. It is very close to its fish ancestry, but still anatomically far from its terrestrial relatives. These creatures still lived in water, but they had a lot of the terrestrial tetrapod anatomical characteristics. Introduction: Before tetrapods existed, all vertebrates were confined to living in aquatic habitats. The only animals that lived on land were arthropods. Through natural adaptations, the fish developed into amphibians. This colossal stage of change made necessary the evolution of new ways o ...
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... At this stage it is estimated that 90% of all companies have at least one macro virus resident somewhere in their computer systems. Types of Viruses Under the main heading of viruses are three types of harmful computer programs, not all of which hide and replicate. The first of these is the Trojan Horse programs, the name of which comes from the Greek legend that told how Greek soldiers gained entry to the city of Troy in a giant, hollow wooden horse and thus captured the city, ending the Trojan War. Though not technically a virus it is still dangerous and could cause permanent damage to your operating system. A Trojan Horse program is a program d ...
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... which breaks down the partially digested foods that, enters the small intestine. Bile has no enzymes but still manages to break down fat into tiny droplets that are ready for faster chemical breakdown. The frog’s stomach is not as complex as a herbivore’s because they have to break down cellulose, which takes a longer time. (Giffard R. & Nat, M 1986) This concludes my study on the digestion system of the frog. FROG'S CIRCULATORY SYSTEM A frog has a closed circulatory system just like humans. This means blood is always enclosed in blood vessels as it circulates the organisms body. Blood also circulates more rapidly and efficiently through a closed ...
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... sources of the fungal spores could be contaminated or wet wood, bird droppings in air ducts, or decaying fireproofing materials. The fungus causes pneumonia in a host with a weak or otherwise compromised immune system. Patients at risk are those undergoing organ transplant or bone marrow transplants, and depending on the type of transplant, mortality rates are as high as 95%. Bone marrow transplant patients, the highest risk group, should be treated like they are immunosuppressed for up to four weeks after the procedure. The portal of entry is through the upper respiratory track. The infection then becomes systemic and is spread into multiple deep organs. ...
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... had an effect on memory. Memory was better for words if they have been categorized and for pictures if they have been named. Experiment 3 showed the same results as the previous two experiments. The fourth experiment, with the introduction of less common objects, subjects could name the words faster than generating a category name for the words. Naming pictures are prone to interference when incongruent words are presented simultaneously. Word naming is not as much influenced by distracting pictures. Pictures and words differ in the amount of information to be filtered out, to get the correct response. The design of this experiment is a within subj ...
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... fact, and thus claimed that Dolly and her “mother” were genetically identical, which sparked a fury of outcry all around the world. The technique of transferring a nucleus from a somatic cell into an egg cell of which the nucleus had been removed, called nuclear transplantation, is an extension of research that had been ongoing for over 40 years. Up until now, scientists thought that adult cells could not be “reprogrammed” to behave like a fertilized egg and create an embryo, but the evidence obtained by Dolly’s success prove otherwise. The issues of cloning have been around for a long time, starting with the publication of Joshua Lederberg’s 1966 article on clonin ...
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