...Main article: Evolution of sexual reproduction It is considered that sexual reproduction in eukaryotes first appeared about a billion years ago and evolved within ancestral single-celled eukaryotes.[2] The reason for the initial evolution of sex, and the reason(s) it has survived to the present, are still matters of debate. Some of the many plausible theories include: that sex creates variation among offspring, sex helps in the spread of advantageous traits, that sex helps in the removal of disadvantageous traits, and that sex evolved as an adaptation for repairing damages in DNA (see Evolution of sexual reproduction). While there are a number of theories, there are two main alternative views on the evolutionary origin and adaptive significance of sex. The first view assumes that sexual reproduction is a process specific to eukaryotes, organisms whose cells contain a nucleus and mitochondria. In addition to sex in animals, plants, and fungi, there are other eukaryotes (e.g. the malaria parasite) that also engage in sexual reproduction. On this first view, the adaptive advantage that maintains sexual reproduction (in competition with asexual modes of reproduction) is the benefit of generating genetic variation among progeny. Furthermore, on this view, sex originated in a eukaryotic lineage. The earliest eukaryotes and the bacterial ancestors from which they arose are assumed to have lacked sex. For instance, some bacteria use conjugation to transfer genetic material between cells;...
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...Lesson 3 Essay Questions: 1. Compare and contrast directional selection and disruptive selection and provide an example of each. Both directional and disruptive selection is a type of natural selection. Natural selection is the differential survival and/or reproduction of organisms as a function of their physical attributes. (phenotype) This results in evolution over many generations. Each mode of selection alters the mean or variance of a phenotypic trait in a population or species. These distributions can be represented in bell curves. Both selection processes can be influenced by human interaction. Directional Selection occurs when an extreme phenotype at one end of a population distribution is favored over all other phenotypes and over many generations it will lead to one distinct form. An example of directional selection is resistance to antibiotics. When an antibiotic is administered a few of the bacteria survive because they are genetically resistant. The surviving bacteria will pass on this phenotype (resistance) to the next generation. Over time the bacteria will be completely resistant to the initial antibiotic. Disruptive selection is an outcome of natural selection in which both extreme phenotypes at the end of a population distribution are favored over the average phenotype. This type of selection favors polymorphism, the occurrence of two different forms in a population of the same species. It can also lead to specification and form two or...
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...WHEN GUESTS ARRIVE AT THE YERKES Regional Primate Research Center in Georgia, where I work, they usually pay a visit to the chimpanzees. And often, when she sees them approaching the compound, an adult female chimpanzee named Georgia will hurry to the spigot to collect a mouthful of water. She'll then casually mingle with the rest of the colony behind the mesh fence, and not even the sharpest observer will notice anything unusual. If necessary, Georgia will wait minutes, with her lips closed, until the visitors come near. Then there will be shrieks, laughs, jumps-and sometimes falls-when she suddenly sprays them. I have known quite a few apes that are good at surprising people, naive and otherwise. Heini Hediger, the great Swiss zoo biologist, recounts how he-being prepared to meet the challenge and paying attention to the ape's every move-got drenched by an experienced chimpanzee. I once found myself in a similar situation with Georgia; she had taken a drink from the spigot and was sneaking up to me. I looked her straight in the eye and pointed my finger at her, warning in Dutch, "I have seen you!" She immediately stepped back, let some of the water dribble from her mouth, and swallowed the rest. I certainly do not wish to claim that she understands Dutch, but she must have sensed that I knew what she was up to, and that I was not going to be an easy target. Now, no doubt even a casual reader will have noticed that in describing Georgia's actions, I've implied human qualities...
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...Australia. Plan. 1. Australia explained in brief 2. States and territories 3. Sistem of governement 1. Australian democracy 2. The constitution 3. The federal government and Parliament 4. State and local government 5. The judiciary 4. The wildlife and conservation 1. Wuldlife 2. Nature conservation 3. Regreening Australia 4. Education 5. International links 5. Cultural growth 1. The australia council 2. Aboriginal arts 6. Australia today 1. AUSTRALIA EXPLAINED IN BRIEF. Australia is an independent Western democracy with a population of more than 17.6 million. It is one of the world’s most urbanised countries, with about 70 per cent of the population living in the 10 largest cities. Most of the population is concentrated along the eastern seaboard and the south-eastern corner of the continent. Australia’s lifestyle reflects its mainly Western origins, but Australia is also a multicultural society which has been enriched by nearly five million settlers from almost 200 nations. Four out of 10 Australians are migrants or the first-generation children of migrants, half of them from non-English speaking backgrounds. In 1991-92, East Asia contributed 41 per cent of settler arrivals. Aboriginal and Torres Strait Islander people totalled 265 378 at the last census, nearly 1.5 per cent of the population. Two thirds of the indigenous people live in towns and cities. Many others live in rural and remote areas, and some still have a broadly...
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...1. Play laser tag once a week. 2. Tip generously. We ALL have to make up for Ted. 3. Don't get married before you're thirty. 4. Always open a door for a lady. Even if she's ugly. 5. Own at least one suit, but twelve if you can. 6. Keep your apartment chilly. Nipples reveal themselves at temperatures below 60° F / 150° C. 7. An easy way to score chicks is to pose as a NASCAR driver because they're rich, dangerous, and nobody knows what they look like because, duh, helmets. 8. Mani-pedis are not just for girls, but drinks with umbrellas emphatically are, Marshall. 9. Two never-fail ways to grease a bouncer: Slip him a $20, or compliment his neck muscles. 10. Have a "guy" for everything. 11. If it seems like the group is almost ready to go, play it safe and yell, "Shotgun!" 12. Remove your keys from your front pocket before receiving a lap dance. It's called respect. Plus, you'll feel it on your junk more. 13. Learning to play the air drums will save your life one day. 14. Give at least as many high fives as you get. 15. Subscribe to "O" magazine. It's full of great tips and tricks for around the house. 16. Have sex in a bathroom stall. 17. If you ever find yourself in a tricky situation, ask yourself, "What would Ted do?" and do the exact opposite. 18. Teacup pigs might be lady-magnets, but they apparently don't digest chocolate. 19. If you ever meet a contortionist, I swear to God don't you ever let her go. I am so serious about this. I gotta sit down or...
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...“The longer you live the longer you should live” –Wiley “Evolution’s a bitch” –Wiley “Suckers are good to eat” –Wiley WHAT HAS EVOLUTION DONE FOR ME What has evolution done for me • Agricultural crops and animal breeding for the past 8,000 years • With the discovery of methods to reconstruct evolutionary relationships there is been a vast increase in the relevance of evolutionary biology to human society. Reconstructing Phylogenies • 1859-1950- No coherent empirical methods • 1950-1966- Emergence of Phylogenetic Systematics • Phylogeny by discovery of the order of evolutionary innovation Ribotyping • Fingerprinting or sequencing RNA • Many diseases have unknown causes • However, diseased tissues can be ribotyped. (Wiley Death Fish) • This process involves extracting DNA from diseased tissues and then sequencing the DNA that codes for rRNA. • If a disease agent such as a bacteria is present, then we will get ribosomal DNA sequences from the host (you) and the bacteria (the infection agent). Ribotyping: Phylogeny matching • Once we have the rDNA sequences, we can plug them into a sequence matrix of all life and see where our unknowns appear on the tree of life. Our Food Chain • Some products are easy to identify, but others are not. • A slab of fish fillet from a sea bass looks like a slab of sih fillet from a farmed Asian catfish. • But the sea bass costs $10/pound while the Asian catfish...
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...Describe and evaluate research into circadian rhythms (8+16) Research into circadian rhythms has assessed the effects of isolating participants from external time cues (exogenous zeitgebers) on our 24 hour cycles, and suggesting that an internal body clock (endogenous pacemaker) creates a free running sleep/wake cycle rhythm of 25 hours. Siffre (1975) * Case study of his own experiences in an underground cave for 2 months. Without any exogenous zeitgebers such as light or cues to guide him, his sleep/wake cycle generally adjusted to a 25 hour cycle, though sometimes changing dramatically up to 48 hours. Aschoff and Weaver (1976) * Designed a temporal isolation study by placing participants in an underground ww2 bunker without an environmental or time cues. * They found that the free running cycle persisted with a sleep wake cycle of 25 hours, sometimes increasing to 29. Weakness into research of circadian rhythms * Lack internal validity. * They removed natural light sources, artificial light from torches and cameras have been shown to reset the endogenous rhythms, thus interfering as an extraneous variable. Exemplified through Czeisler et al (1999) * Altered participants’ circadian rhythms down to 22 hours and up to 28 only using dim lighting to alter his release of melatonin from the pineal gland. * Findings do not reflect true isolation and have lower internal validity, so his rhythm may not have adjusted so well if he had been truly...
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...Dedicated to St John the Blasphemist Saint of Freakin‟ Awesome Holy Texts Cover Art by MonkeysInACan aka Captain Chris Taylor, Tigger_the_Wing, and Rev. Rowan Redbeard Table of Contents Proclamations of the Councils of Olive Garden.........................................................................1 Second Announcement Regarding Canonical Belief......................................................................2 Third Announcement Regarding Canonical Belief.........................................................................3 The Old Pastament........................................................................................................................4 The Book of Midgets/Midgits.........................................................................................................5 The Creation of Mankind..............................................................................................................14 A Reading From the Book of Fusilli..............................................................................................15 The Book of Penelope....................................................................................................................17 The Book of Linguini.....................................................................................................................20 The Torahtellini Part 2............................................................................................................
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...THE EFFECTIVENESS BANANA (MUSA X PARADISIACA) PEELS USED AS FERTILIZER APPLIED IN DIFFERENT KINDS OF PLANTS SAMPLES RESEARCHER: BERLENE GAIL H. LAMA CHAPTER I INTRODUCTION Background of the study A banana peel, known as a banana skin in British English, is the outer covering of the banana fruit. As bananas, whether eaten raw or cooked, are a popular fruit consumed worldwide, with yearly production over 145 million tonnes in 2011, there is a significant amount of banana peel waste being generated as well. Banana peels are used as feedstock as they have some nutritional value. Banana peels are widely used for that purpose on small farms in regions where bananas are grown. There are some concerns over the impact of tannins contained in the peels on animals that consume them.[3][4] Banana peels are used as feedstock for cattle, goats, pigs, poultry, rabbits, fish and several other species. The specific nutrition contained in peel depends on the stage of maturity and the cultivar; for example plantain peels contain less fibre than dessert banana peels, and lignin content increases with ripening (from 7 to 15% dry matter). On average, banana peels contain 6-9% dry matter of protein and 20-30% fibre (measured as NDF). Green plantain peels contain 40% starch that is transformed into sugars after ripening. Green banana peels contain much less starch (about 15%) when green while ripe banana peels contain up to 30% free sugars. Banana peels are also used for water purification...
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...Module 3 Waves and the Electromagnetic Spectrum Topic: Waves 1. What is a wave? A wave is vibration that travels and all waves are created by something vibrating. Waves transport energy but do not transport mass. 2. Describe the following terms associated with waves: a. amplitude height of wave b. wavelength length of a wave c. frequency number of waves per second (Hz) d. period how long a wave lasts when it arrives at a fixed point (measured in seconds) 3. What are radio waves? An electromagnetic wave of a frequency used for long distant communication. 4. Explain the difference between a transverse wave and a longitudinal wave, and give examples of each. In a longitudinal wave, the vibration travels in the same direction that wave travels. Examples of longitudinal waves include: Sound, p-waves (earthquakes) In a transverse wave, the vibration direction is perpendicular to direction that wave travels. Examples include: Light/electromagnetic, (radio, microwave, xray, etc.), water waves, swaves (earthquakes). The major difference between longitudinal and transverse waves is their direction. Longitudinal waves move left to right while transverse waves move up and down. 5. Compare and contrast: light waves vs. sound waves Light waves are transverse and sound waves are longitudinal. Light waves can travel through a vacuum but sound waves cannot. Speed of light is nearly 300 million m/s while sound has a speed of about 340 m/s...
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...6 Cellular Respiration: Obtaining Energy from Food Muscles in action. Sprinters, like all athletes, depend on cellular respiration to power their muscles. CHAPTER CONTENTS Energy Flow and Chemical Cycling in the Biosphere 92 Cellular Respiration: Aerobic Harvest of Food Energy 94 Fermentation: Anaerobic Harvest of Food Energy 101 CHAPTER THREAD Aerobic versus Anaerobic Lifestyles BIOLOGY AND SOCIETY Marathoners versus Sprinters THE PROCESS OF SCIENCE What Causes Muscle Burn? EVOLUTION CONNECTION Life before and after Oxygen 91 102 103 Aerobic versus Anaerobic Lifestyles BIOLOGY AND SOCIETY Marathoners versus Sprinters Track-and-field athletes usually have a favorite event in which they excel. Some runners specialize in sprints of 100 or 200 meters. Others excel at longer races of 1,500, 5,000, or even 10,000 m. It is unusual to find a runner who competes equally well in both 100-m and 10,000-m races; most runners are more comfortable running races of particular lengths. It turns out that there is a biological basis for such preferences. The muscles that move our legs contain two main types of muscle fibers: slow-twitch and fast-twitch. Slow-twitch muscle fibers can contract many times over a longer period but don’t generate a lot of quick power for the body. They perform better in endurance exercises requiring slow, steady muscle activity, such as marathons. Fast-twitch muscle fibers can contract more quickly and powerfully than slow-twitch fibers but also...
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..."Why is Sex Fun? is the best book on the subject I've read. This lively exploration of our sexual heritage offers fascinating reading for anyone curious about why lovers do what they do." -Diane Ackerman, author of A Natural History of the Senses "I am so jealous of Jared Diamond, for he writes with such an elegant simplicity! Here, he takes a loot at the endlessly fascinating topic of human sexuality His convincing arguments should persuade xm that there are very special reasons why we evolved to use sex for recreation as well as for procreatim whereas most other mammals are denied that pleasure.... It is a great little book, by one of the worlds foremost biological philosophers." -ROGER Shohl Professor of Physiology Monash University Australia "Once again Jared Diamond provides us with answers to questions we may never have stopped to ask, but wish we had. In this long essay Diamond explains that recreational sex, while not unique to humans, is a rare behavior in the animal world. Above all, we learn, sexual activity divorced fron procreation is not only part of what it is to be human, but the very crux of our evolutionary success." -Bettyaxn Kevles. author of Naked to the Bonn Medical Imaging in the Twentieth Centnty The Science Masters Series is a global publishing vonture consisting of original science books written by leading scientists and published by a worldwide team of twenty-six publishers assembled by John Brockman. The series was conceived by Anthony Cheetham of Orion...
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...Signs appear in everyday contemporary societies. Signs are saturated with a lot of meanings and they relate to any language and are there to make us understand things through relating words with concepts like the word ‘silence’ which is a sign of communication that is indicative of meaning and it is ideological, it is also power to talk. Sign theory is an eccentric war of communication. It focuses on the discourse analysis where it focuses on language, power and ideology. Intelligence services are a key component of every state and their mandate is to ensure the security of states and they make use of the sign theory to supply the policy makers with information or intelligence which is fundamental in the policy making process. Evaluation and analysis’ role is to cast information into its proper intelligence framework and in the process minimising being biased. If evaluation and analysis is quality the intelligence given to policy makers will help policy makers to come up with quality policies and if the evaluation and analysis is poor obviously the policy makers will come up with ineffective policies. There are repercussions if intelligence services fail to analyse. Sign theory help in deductive, inductive and abductive types of reasoning. In this discourse I will define the sign theory, evaluation, analysis, four tools of analysis and the implications of sign theory to evaluation and analysis as a process which is scientific, logical, methodological and verifiable. Theory is...
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...P LA T O and a P LAT Y P U S WA L K I N TO A B A R . . . Understanding Philosophy Through Jokes < T H O M A S C AT H C A RT & D A N I E L K L E I N * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * P l at o a n d a P l at y p u s Wa l k i n t o a B a r . . . PLATO and a PLAT Y PUS WA L K I N T O A B A R . . . < Understanding Philosophy Through Jokes Th o m as Cat h c a rt & Dan i e l K l e i n A B R A M S I M AG E , N E W YO R K e d i to r : Ann Treistman d e s i g n e r : Brady McNamara pro d u c t i on m anag e r : Jacquie Poirier Cataloging-in-publication data has been applied for and may be obtained from the Library of Congress. ISBN 13: 978-0-8109-1493-3 ISBN 10: 0-8109-1493-x Text copyright © 2007 Thomas Cathcart and Daniel Klein Illlustration credits: ©The New Yorker Collection 2000/Bruce Eric Kaplan/ cartoonbank.com: pg 18; ©Andy McKay/www.CartoonStock.com: pg 32; ©Mike Baldwin/www.CartoonStock.com: pgs 89, 103; ©The New Yorker Collection 2000/ Matthew Diffee/cartoonbank.com: pg 122; ©The New Yorker Collection 2000/ Leo Cullum/cartoonbank.com: pg 136; ©Merrily Harpur/Punch ltd: 159; ©Andy McKay/www.CartoonStock.com: pg 174. Published in...
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...ASIA CONTINENT, ASIA FACTS Of all the seven continents, the continent of Asia is the largest with respect to both area and population while Australia being the smallest in both regards. The total area of Asia is calculated to be 43,810,582 kilometers square, covering 30% of the total earth's land and 8.66% of the total earth's surface. This continent shares its border with Ural Mountains to the East, the Arctic Ocean to the North, the Pacific Ocean to the West and the Indian Ocean to the South. The highest point in the World is Mount Everest with a height of 8,848 meters. This mountain is situated in the Tibetan region of the Himalayas that is situated in this gigantic continent. Other Asia facts includes the facts about Asian rivers. As, the rivers are considered to be the most needed natural phenomenon on earth and are immensely important geographically, biologically, historically and culturally. So, the 3rd longest river in the world; river Yangtze (6,211 km) is in Asia and flows through China. Desert is an area or landscape which gets least precipitation thus providing unfavorable conditions for the growth of plants and the survival of life. The largest desert in Asia is the Gobi desert measuring 281,800 km square. Climate and weather are important factors in tourist's decision making and influence the successful operation of tourism. Climate of Asia largely depends on its location and physical geography. This continent comprises of 53 countries including Russia and...
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