Population Biology Basics

Populations are groups of individuals belonging to the same species that live in the same region at the same time. Populations, like individual organisms, have unique attributes such as growth rate, age structure, sex ratio, and mortality rate Populations change over time due to births, deaths, and the dispersal of individuals between separate populations. When resources are plentiful and environmental conditions appropriate, populations can increase rapidly. A populations ability to increase at its maximum rate under optimal conditions is called its biotic potential. Biotic potential is represented by the letter r when used in mathematical equations. Keeping the Population in Check In most instances, resources are not unlimited and environmental conditions are not optimal. Climate, food, habitat, water availability, and other factors keep population growth in check due to environmental resistance. The environment can only support a limited number of individuals in a population before some resource runs out or limits the survival of those individuals. The number of individuals that a particular habitat or environment can support is referred to as the carrying capacity. Carrying capacity is represented by the letter K when used in mathematical equations. Growth Characteristics Populations can sometimes be categorized by their growth characteristics. Species whose populations increase until they reach the carrying capacity of their environment and then level off are referred to as K-selected species. Species whose populations increase rapidly, often exponentially, quickly filling available environments, are referred to as r-selected species. Characteristics of K-selected species include: Late maturationFewer, larger youngLonger life spansMore parental careIntense competition for resources Characteristics of r-selected species include: Early maturationNumerous, smaller youngShorter lifespansLess parental careA little competition for resources Population Density Some environmental and biological factors can influence a population differently depending on its density. If population density is high, such factors become increasingly limiting on the success of the population. For example, if individuals are cramped in a small area, the disease may spread faster than it would if population density were low. Factors that are affected by population density are referred to as density-dependent factors. There are also density-independent factors which affect populations regardless of their density. Examples of density-independent factors might include a change in temperature such as an extraordinarily cold or dry winter. Intra-Specific Competition Another limiting factor on populations is intra-specific competition which occurs when individuals within a population compete with one another to obtain the same resources. Sometimes intra-specific competition is direct, for example when two individuals vie for the same food, or indirect, when one individuals action alters and possibly harms the environment of another individual. Populations of animals interact with each other and their environment in a variety of ways. One of the primary interactions a population has with its environment and other populations is due to feeding behavior. Types of Herbivores The consumption of plants as a food source is referred to as herbivory and the animals that do this consuming are called herbivores. There are different types of herbivores. Those that feed on grasses are referred to as grazers. Animals that eat leaves and other portions of woody plants are called browsers, while those that consume fruits, seeds, sap, and pollen are called frugivores. Predators and Prey Populations of carnivorous animals that feed on other organisms are called predators. The populations on which predators feed are called prey. Often, predator and prey populations cycle in a complex interaction. When prey resources are abundant, predator numbers increase until the prey resources wane. When prey numbers drop, predator numbers dwindle as well. If the environment provides adequate refuge and resources for prey, their numbers may again increase and the cycle begins again. Competing Species The concept of competitive exclusion suggests that two species that require identical resources cannot coexist in the same location. The reasoning behind this concept is that one of those two species will be better adapted to that environment and be more successful, to the point of excluding the lesser species from the environment. Yet we find that many species with similar requirements do coexist. Because the environment is varied, competing species can use resources in different ways when competition is intense, thus allowing space for one another. When two interacting species, for example, predator and prey, evolve together, they can influence the evolution of the other. This is referred to as coevolution. Sometimes coevolution results in two species that influence (both positively or negatively) from each other, in a relationship referred to as symbiosis. The various types of symbiosis include: Parasitism: One species (parasite) benefits more than the other species (host).Commensalism: One species benefits while a second species is neither helped nor injured.Mutualism: Both species benefit from the interaction.

Anorexia Nervosa Is An Eating Disorder - 1373 Words

Anorexia Nervosa is an eating disorder that a lot of girls and even boys suffer from. It deals with distorted body image issues that turn into an obsessive control of food intake. It can start as a normal diet that gets taken too far. One might limit themselves to a very low calorie diet and over exercising keeping him or her below a healthy weight. The body goes into starvation mode if you do not eat around two thousand calories a day and a person with anorexia on average eats less than six hundred calories per day (Overview - Anorexia nervosa - Mayo Clinic, 2016). To put that into perspective, a banana is about one hundred calories. When your body is starving, it stars hoarding calories and your metabolism does not have to work as†¦show more content†¦There are a few ways to try and treat this disorder. Because it is a mental disorder the first approach a lot of parents take with their child is to get them into some sort of counseling. A counselor can talk to the child or adult suffering from this disease and see if they can try to talk to them and get through to them. They might be able to figure it is deeply rooted from something in their past. They have to try to talk the sick person into trying to want to eat a healthy amount of food and love his or her body again. There are some drugs that can be prescribed to try and help with this which include â€Å"Olanzapine (Zyprexa), Citalopram (Celexa), Fluoxetine (Prozac)† (Overview - Anorexia nervosa - Mayo Clinic, 2016). If a person is refusing help and is getting to a dangerously low weight, they can be hospitalized and force fed from a feeding tube. I did watch a show from the UK that had a program for girls with eating disorders. They were sent away from their parents to live in a home with other girls with eating disorders and were monitored very closely. They were required to eat a certain amount of calories per day and watched extremely closely. They were not allowed to use the restroom u ntil three hours after finishing a meal in fear that they might be hiding food in their mouths and spit it out or some girls would make themselves throw up what they had just eaten. Exercise was limited and any type

Smell and Memory free essay sample

What is the best way to commit something to memory? Memory is a combination of the processes used to acquire, store, retain, and retrieve information (Cherry, 2012). Students, professionals, children, and researchers would all benefit from knowing how to best encode information and ensure that information remains imbedded in ones long-term memory banks. The study of human memory has been a major priority for cognitive psychologists for many years. One of the main focuses has been with memory and the five basic human senses. Is it easier to recall a memory that one has seen , heard, touched, tasted, or smelled? In terms of quickness and effectiveness, from a biological and physical standpoint, the sense of smell is the most effective in retaining and retrieving information out of all five senses. The process of in which information is transported into long term memory is called encoding (Goldstein, 2011). This process can be completed in several different ways using the different senses. Events in one life can be committed to memory via sight. Most would say that sight is the most effective sense in recovering memories because when one tries to remember a past event, they attempt to visualize it. Simple visualizations of past events usually only come in flashes and dont give an accurate, detailed depiction of the events that occurred. Hearing is the same, if one focuses on the auditory aspects of a memory, they will only recall what was heard and not many other details of the account. The most detailed and fully formed recalls typically come from memories that are linked with strong emotions. Emotional memories cause a release of hormones from the adrenal glands and these hormones influence the effects or neurotransmitters in the brain, enhancing ones memory (Wade, 2012). Since  emotions are so closely related to memory, one can assume that the sense with the closest relationship to emotions would be the sense that is most able to store and retrieve information accurately. The amygdala is a set of neurons located deep in the brains medial temporal lobe and plays a key role in the processing of emotions (ScienceDaily, 2012). The primary olfactory cortex, in which the higher level processing of hearing takes place forms a direct link with the amygdala (Herz, 1996). Only two synapses serarate the olfactory cortex from the amygdala, which is involved in experiencing emotion and emotional memory (Herz, 1996). So when one smells something, it immediately triggers an emotional response. That smell is then committed to memory emotionally, and in the future when that particular smell is experienced again, the emotions felt will allow the person to retrieve a detailed account of what was going on when that smell was first experienced. For example, if one happened to be staring out the window watching a dog chase a squirrel and smelled that their grandmother was baking chocolate chip cookies, years later when smelling those cookies again, that emotional response garnered before could bring about a detailed account of that dog chasing the squirrel. The hippocampus is a part of the forebrain, located in the medial temporal lobe and is a critical tool used for storing memories (Buzsaki, 2010). The hippocampus has also been considered the brains éÆ' ½earch engine allowing for quick and efficient searches for deposited memories in the brain (Buzsaki, 2010). The hippocampus provides a storage for information and dedicates it to long term memory, and then later provides the ability to search through that database of information for specific memories and information. Only three synapses separate the olfactory nerve from the hippocampus (Herz, 1996). Given this information, one can see that the sense of smell carries a direct link to the storing of information, and also a direct link with the subsequent retrieval of that information. Humans tend to underestimate the role of smell in our every day lives. Most mammals actually recognize smell as their most important sense and rely on it constantly for many of their daily activities. Animals use their sense of smell to hunt food, locate members of their family or pack, lure possible  mates for reproduction, and even communicate. Members of the canine family often use urine to mark their territories, committing the smell of the urine to memory so they can use that memory to locate their territories and ward off other animals (Ito, 2000). Many animals when they are first born are unable to see, and use their sense of smell to identify their mother (Ito, 2000). Some animals, when they birth their young identify them using their sense of smell, and if that scent is compromised by another animal or person, the parent will reject the young (Ito, 2000). Animals also learn better using their sense of smell. In a 1993 study, rats were presented with a drinking tube containing quinine hydrochloride (Slotnik, 1993). The hydrochloride had a bad taste and the time it took for the rats to stop going to the drinking tube was recorded (Slotnik, 1993). When the hydrochloride drinking tube was associated with a specific scent, the rats learned to not drink from it much faster than when the water was associated with a different color, sound, or consistency (Slotnik, 1993). The rats learned quicker when the tainted water was associated with smell than any other sense. Humans would be a lot more effective in storing and retrieving their memories if they took the example given my most mammals and utilized the olfactory nerve system more effectively and relied on it more often. One important aspect of committing information to long term memory is rehearsal. Rehearsal is necessary for commiting things to memory because typically the sensations we see, hear, and feel dont remain for long. After reading a sentence, the vision of that sentence doesnt stay there, it passes. So the best way to commit that sentence to memory would be to read that sentence over and over again until it sticks, and even then it only commits it to short term memory (Goldstein, 2010). One could also not read it again, but just repeat it over and over until it is committed to memory using the auditory senses. This shows that committing information to memory using other senses requires work on ones part. When it comes to the sense of smell, it is the slowest of all senses. It not only takes the brain longer to perceive olfactory stimuli; the sensation of an odor also persists for greater lengths of time than do sensations of vision or audition (Herz, 1996). One does not have to do any work to commit a smell to memory because the body automatically conducts its own form of rehearsal by allowing the  sensation to linger until it is committed to memory. Olfactory receptors most readily receive information from the physical world and therefore are able to code memories for things like emotion or events more efficiently. Several studies have been conducted with humans to determine what senses have the most effect on memory. One 1990 study examined memory for common odors and odor names encoded with visual, verbal, and olfactory elaborations (Lyman, 1990). In this experiment several groups of people were placed in a room and either presented with a group of odors and the name of that odor, visually given a list of names of objects associated with an odor, or verbally given a list of names associated with an odor (Lyman, 1990). A week later these groups were brought back in and asked to recall these lists given olfactory, auditory, or visual clues. The group that was presented with the smells again performed a lot better in recalling the name associated with those smells (Lyman, 1990). According to this study and several like it, the olfactory receptors are more effective at storing and retrieving memory; however, studies have also been done to decide whether interference plays a part when storing memory. When one is listening to a lecture and trying to commit what the lecturer is saying to their long term memory, background noise such as a car outside, another student sneezing, or a phone ringing is known as auditory masking (Goldstein, 2010). This masking reduces the persons ability to remember what was being said at the time. Visually, if one is watching a television show and there is something moving in their peripheral vision, that distraction could affect the persons memory of that television show. So in order to determine whether interference also plays a part in the sense of smell and how it is compared to the other senses and their types of interference, a research study was conducted in 2003 by Gesualdo Zucco. In this study, participants were asked to smell 30 odors while performing other tasks (Zucco, 2003). These tasks included things such as drawing an image, recounting a specific episode from their life, or naming a word and giving the definition (Zucco, 2003). Participants that were asked to conduct these tasks while smelling the odors were later able to recollect these odors just as well as the participants that smelled the odors without having to perform  a separate task (Zucco, 2003). In a second study conducted by Zucco, participants were exposed to 15 olfactory stimuli, 15 auditory stimuli, or 15 visual stimuli and all exposed to similar interfering conditions (Zucco, 2003). After being asked to recall the different stimuli later, it was shown that the interference affected recollection for the visual and auditory stimuli but not at all for the olfactory stimuli (Zucco, 2003). This study shows that not only is memory for odors represented on a separate and unique memory system, but also a more effective memory system than visual and auditory stimuli. Given the fact that the olfactory system holds closer links to the amygdala and hippocampus, automatically conducts its own form of rehearsal, and is less affected by interference, one can conclude that the sense of smell is the most effective sense in storing and retrieving memories; however, there is one downside to relying on the sense of smell to recall memories. Memories retrieved by the sense of smell are often subject to bias. A 1987 study showed that women asked to retrieve memories based on specific neutral words while also being exposed to certain odors recalled these memories in a negative or positive light based on the type of odors they were given (Ehrlichman, 1988). Those that were exposed to unpleasant odors recalled their memories as negative, while those exposed to pleasant odors recalled their memories as more positive (Ehrlichman, 1988). Each sense plays its part in memory retrieval and the best way to accurately and in detail commit an event or information to memory and later retrieve that event or information is to use as many senses as possible when encoding. But the most effect sense in storing and retrieving detailed information or events is the sense of smell.

British Home Front Ww1 Essay Research Paper free essay sample

British Home Front Ww1 Essay, Research Paper Modern History Assessment Task # 1 degree Celsius ) Britains immediate reaction to World War I was a combination of aroused expectancy, wonder and nationalism. The bulk of people were swayed by the initial euphory and the state settled into a province of loyal integrity. Initially, Britain was certain that the war would be over by Christmas. They had merely of all time before seen little eruptions of struggle like the Russo-Japanese War, which was quiet insignificant when compared to the consequences of the Great War to come. Whether it was soldiers about to go forth for the combat or adult females come ining the work force, the general vibration was enraptured and eager to lend. Britain contributed exceeding support with surprisingly high liquors. However, this merely lasted until Christmas of 1914. By this clip, trenches had been dug and strong defensive places were in topographic point. The war didn? T seem to be traveling anyplace. This caused concern as harmonizing to the authorities the war should hold over by now and all the British dorsum at place. By mid 1915 a deadlock had developed. General civilian attitudes started to turn. Peoples were non so confident and loyal as they one time were at the beginning of the war. Wounded soldiers began to return place and narratives from the frontline were out in the unfastened. As the war state of affairs began to look inexorable, the authorities began to command things like the media and baning letters that were to make the place forepart in order to maintain morale every bit high as possible. The Gallipoli run was the following major effort to better the civilians? attitudes. Unfortunately the Gallipoli run was an absolute catastrophe. Gallipoli turned out to be eight months of a similar ordeal that Britain went through merely a short piece earlier in France. Back place the British imperativeness were shocked at the failure. As a consequence, Winston Churchill was sacked from his place and one time once more high liquors deteriorated. The lead up to the conflict of the Somme yet once more improved British citizens attitudes and all were confident of a decisive discovery. Yet once more it was a narrative seen merely excessively many times before. Britains great outlooks shortly turned to letdown and indignation. On the first twenty-four hours of the conflict, 60 thousand British work forces were killed. The imperativeness back place were wholly stunned. This was the turning point of the war. The Germans had seized the advantage and blockaded the English Channel with the extremely effectual U-boat run. This had an about annihilating consequence as indispensable nutrient and other supplies were no longer to make Britain from topographic points like Australia. Britain became despairing, as civilians had lost a great sense of hope as they began to hunger to decease. The 2nd full twelvemonth of war was stoping ; triumph and peace were nowhere in sight. The really effectual curate for weaponries, Lloyd George felt the authorities was non making plenty to win. In November 1916, he said in private: ? We are traveling to lose the war? . Asquith resigned as premier curate and Lloyd George took over. He instantly reorganised the authorities for the construct of Total War. He set up a little war cabinet of top curates that he felt could steer the war attempt. There were new ministries ( Labour, Food, Shipping, Pensions ) and many sections and commissions. Research workers gathered accurate information about what the state was bring forthing and what was needed to win the war. Peoples didn? T know what to believe of the new issues and ways of life brought approximately by the extremely active and motivational Prime Minister Lloyd George. Most followed in his assurance stance and anticipated a alteration of melody from the frontline. 1916 was known as the twelvemonth of large offenses. However, it was large-scale on both the British place forepart every bit good as the front-line. British citizens both at place and in the thick in combat all shared the similar position that war was snake pit. 750 000 Gallic and British had died in the runs that were meant to win the Great War. Back place, muster had been introduced, milking every last able-bodied British citizen, go forthing merely despaired adult females and shaky-handed 70 twelvemonth olds working in topographic points such as weaponries mills. Governments were making every bit much as possible to keep on and keep morale. Britain was seeking to tap every last resource for every last supply. However, the battle to last was plenty. The British round the German U-boat run and liquors were lifted. The entry of the Americans, although little, was besides a major encouragement. In 1918, major allied offenses had driven the Germans back every bit far as their boundary line. This was without any major attempt from the Americans and so was great inspiration for the British civilians to keep on. Victory was one time once more in sight. Finally, on the 11th of November 1918, the cease-fire was signed which signified the alleviation of the long anticipated exhilaration and avidity which had ironically greeted the war merely four old ages earlier. The clip of exhilaration of traveling off to war ; choler at the truth of the front-line ; the defeat of a deadlock ; the deathly expectancy of scanning the day-to-day published casualty lists ; the assurance that the following offense would be the last ; and all-round assorted emotions came easy to a holt on the British place forepart as soldiers did and did non return to there household and lives they had left behind so long ago. HISTORY Student # 571 Modern History Assessment Task # 1 B ) The war dramatically changed the lives of adult female in both Britain and Germany. In the universe of 1914, criterions were high that adult females were? taken attention of? by work forces? . The thought had been in pattern for old ages that adult females could non pull off their ain lives. Nor particularly did they think that adult females could make a adult males work. Unlike the Australian adult females of this clip, the British adult females weren? t even allowed to vote as they were thought to non hold a comprehendible head to be able to hold a good apprehension of political relations. A little group of adult females called? Suffragettes? in Great Britain had been recommending the ballot for many old ages. Womans in this society had no dominant function but to look after the household, or in the instance of the individual adult females from hapless households, worked as custodies and amahs. The early haste of voluntaries to the front-line and subsequently the muster of work forces led to a deficit of work force on the British place forepart. The early months saw aggregate unemployment follow the eruption of war in both sexes. In September 1914, about 44 % of adult females workers were unemployed. Over the following few old ages the state of affairs was slightly reversed as workers became scarce. There was no 1 left to make full the topographic points of those who had enlisted but the adult females. Every twenty-four hours supplies such as nutrient and vesture were non surprisingly needed immediately. Workrooms were set up to learn new accomplishments like dressmaking, plaything devising and cleansing in order to set up some foundations for ego sufficiency, for which they were paid blue rates in comparing to that of those work forces and antecedently enjoyed. Even so, the industry besides required more workers, particularly after the consequence of muster. Trade brotherhoods opposed adult females taking work forces? s occupations for good but about instantly adult female were working in weaponries and other mills. Women become bus and tram music directors, railroad ticket aggregators, mailmans, gravedigger, lamplighters, mechanics and even jurisprudence hatchet mans. They worked in offices, dockyards, research labs and breweries and became laborers of the land and farm. One adult female helped her male parent run his concern: ? My male parent was a blacksmith? During the Great War there was no strikers to do the Equus caballuss? places, so at the age of 16 I did all the contact, and between us we managed to maintain the Smithy unfastened. At the clip I was analyzing for my matriculation at the Holyhead Grammar School, which means that the Equus caballuss? places had to be made really early in the forenoon before cycling lives stat mis to the school. ? Womans rapidly adapted to there new functions and enjoyed the duty that made them experience a portion of it all. However some of the labor was really intense and unsafe. Most of all, adult females worked in weaponries mills doing arms of war. The? munitionettes? as the adult females were called, were told ; ? A weaponry worker is every bit of import as a soldier in the trenches and on her his life depends. ? A Gallic general said ; ? If the adult females in war mills stopped for 20 proceedingss, we should lose the war. ? They were good paid but endured really long hours. They did a big scope of occupations, such as doing slugs and shells, piecing detonating devices, smoothing the clip fuses and shells, and make fulling the shells with gunpowder. The shells were filled with TNT, which was toxicant, and long exposure to it frequently turned the tegument yellow. Peoples like this were frequently called? Canary Islandss? . Besides this danger, detonations such as the accident in the Lon don mill in 1917, which killed 69 people, were besides common and feared. Australian adult females urgently wanted to fall in the services in order to see combat. Australian adult females were rejected and so travelled over the Britain were they could prosecute in work that took them to the front-line. During the war, 25 000 British adult females worked behind the front-line in organisations such as the First Aid Nursing Yeomanry ( FANY ) or the Voluntary Aid Detachment ( VAD ) , which involved nurses covering with some of the worst horrors of the war: ? Sometimes I helped in the operating room. Amputated limbs were merely swept or thrown out into the courtyard? Most of the work forces were so severely smashed that each needed a nurse to himself. ? Womans became fundamentally more able, dependent and autonomous. Married miss ran the household place on their ain. Single girls went to eating houses and theaters with out an bodyguard. Thingss like frock manners changed to go more practical. Immediately, it was adult females worried about their menfolk in the armed forces, get bying with raising prises and revenue enhancements and deficits while frequently alone and inquiring when it will all terminal. However, finally the war was determining the adult females? s hereafter. Before the war, adult females had been expected to get married and content themselves with household and domestic work. Then, it was considered unsuitable or a adult female to work ; now, it was considered disloyal non to! HISTORY Student # 571 Modern History Assessment Task # 1 a ) In Britain, the eruption of the Great War was greeted with tremendous enthusiasm. Peoples were exited, proud and wanted to demo their love for their state. Almost instantly, work forces enlisted through recruiting bureaus, swayed by the glamor of contending a war for your ain state. This initial image was insisted by propagandist stuff such as postings stating work forces? Your state needs you! ? and? Enlist now! ? Men rushed to fall in the? colorss? , otherwise known as the regular ground forces. Music halls resounded with choruses of? We wear? T want to lose you but we think you ought to travel? ? The force per unit area on work forces to acquire into ordinance khaki was tremendous. It was about a shame to be seen in the street without a uniform. After a few months, it became apparent that the Alliess needed a batch more people than they had to contend with if they wanted to interrupt away from this deadlock that had developed. Work forces were encouraged to enlist with their b uddies in order to organize? buddies battalions? which may hold sounded more inviting. Guilt was besides used as a manner of promoting civilians to enlist. Men were ridiculed and called cowards in the street. They normally received a white plume in the male, stand foring that of a spiritless poulet. Recruitment was a immense issue that was encouraged, and subsequently enforced through muster, strongly by the British authorities. War forced other alterations on the British people. They had to accept the ordinances imposed by the Defence of the Realm Act ( DORA ) passed in 1914. For grounds of national security, the Act besides interfered in people? s lives by baning narratives, images, journals, letters, movies and sounds from the war forepart, were censored to merely let British/Allied positives and German negatives to make the populace? s eyes and ears. All the soldiers? letters were read prior to being sent place and the maintaining of dairies was out. Censoring was put in topographic point to maintain liquors high and prolong popular support for the war in Britain. By demoing the populace merely the positives of war, so there is nil to cut down the inducement to travel off to war cause? Britain needs YOU! ? Propaganda was a major maneuver used on the place forepart to hold people believing that it is at that place ain responsibility to travel to war and to experience guilty if they didn? T. Many different attacks were taken in relation to propaganda. Images of large, endangering soldiers indicating at you to come and enlist which created a personal engagement. Others showed a male parent being shammed by his kids who ask him what he did in the Great War. Even groups like the socialists, who were pledged to non-violence, most supported the war. Even the suffragettes, after some initial heart-searching, threw themselves into war work. Furthermore, the gap of belligerencies led to xenophobia? hatred of aliens. Propaganda was extremely effectual in making an eruption of enthusiasm Recruitment, Censorship and Propaganda were all used in concurrence with each other in order to be successful. Posters and marks of propaganda were ab initio used to enroll soldiers. In fright of civilians going disheartened, censoring was introduced to curtail lay waste toing narratives from the forepart so that enlisting remained strong due to a despairing demand of soldiers to interrupt the deadlock and launch a major offense. In a sense, censoring is a portion of or basically a manner of propaganda as the subject of war is glorified to promote recruitment. Year 12 Modern History Assessment Task # 1 British Home Front WWI