A Bat out of Hell

The Sutton Grammar School Biology Magazine Issue 6

Edited by: Christopher Slade, Nichols Weise and Samuel Amis Life A Bat Out Of Hell Everybody has heard the myths that follow Dracula, but just how valid are they? The true story of the misunderstood Vampire Bat point on the unsus- Within minutes of beginning to pecting animal where feed, the bat is already excreting the blood flows close large amounts of blood plasma, to the skin. Unique which has no nutritional value. amongst bats and However, even with this rapid even mammals in processing and digesting of the general, the Common blood, the bat has still gained 20- Vampire Bat is as 30% of its own bodyweight in an manœuvrable on the average 20-minute feed. To take ground as in the air, flight, the bat uses its thumbs to walking on its leap high into the air, propelling thumbs, forwards, itself rapidly upwards before ex- backwards and side- tending its 20 cm wingspan to ways in much the take flight. It then returns to its same way as a spider roost around 2 hours after having

does. It approaches set out. its prey on the (continued on page 2) ground, running at speeds of up to 7.9 km/h. If the animal is Article by David Cornish areas from Central and Latin hairy, it uses its canines and cheek Inside This Issue of Life An unfortunate, shared name has America in the North to Brazil, teeth to shear an exposed patch of Chile and Argentina further south. flesh. It then uses its razor sharp made the vampire bat a creature of Amis’ Ailments In many parts of Central and Latin incisors (which lack enamel, mak- 2 myth and misunderstanding. As- America, these bats are regarded ing them easier to keep sharp) to Vampire Bats, sociations with Dracula, justified as dangerous pests, where large make a cut 7 mm long and 8 mm 2 (continued) only by a mutual love of blood, areas of forest are cleared for cattle deep. Vampire bat saliva contains have created endless superstition grazing. Of the three species, only a number of anticoagulants such The Neurology Page - 3 and folk stories: that these re- the Common Vampire bat feeds on as ‘draculin’ to prevent the vic- amygdalae markable flying mammals drink mammal blood (the Hairy-Legged tim’s blood from clotting, keeping Science In Crime human blood, or are capable of Vampire bat and the White- red blood cells from sticking to- 3 shifting in form between man and Winged Vampire bat feed on the gether and veins near the wound Four Limbs Extra bat. However, what the myths blood of birds), but due to supersti- from constricting. This ensures a 4 tion and the potential of the bats to constant blood flow, which the bat conceal is one of the most highly Invasive Species carry rabies which could be passed then ‘laps’, rather than sucks, a 4 evolved and perfectly adapted to the cows, it has become routine popular misconception. animals living on the planet Earth Marfan Syndrome for the ranchers to dynamite and 5 today. burn caves and roosts. A typical vampire bat weighs 40g Molecule of the Month 5 but will consume up to 20g of Vampire Bats (all three species, The Common Vampire Bat only blood in a single feed. This would Sports Science 6 which belong to separate genera) hunts when it is fully dark, using make it impossible for the bat to are native to the Americas, inhab- low energy sound pulses to locate then fly away but for a number of Life Quiz 6 iting tropical and sub-tropical prey, and then infrared to find a other adaptations. Page 2 Life. Issue 6 Amis’ Ailments ‘A look at some of the more gruesome and obscure diseases, that plague mankind’ - Necrotizing Fasciitis By Sam Amis the subcutaneous tissue below, a As far as the producers of medi- large mass of tissue may have cal dramas are concerned, every- already died. Despite the title of one who walks into a hospital ‘flesh eating’ it is the toxic by- nowadays has an aggressive, products of bacterial metabolism debilitating and exceptionally that causes the decay of the tissue rare condition, that they con- and the subsequent surgical re- tracted in some bizarre and en- moval of any dead and diseased tertaining way. Fortunately, this tissue. It is not uncommon for is not the case and the majority someone suffering from this dis- of a doctor’s diagnoses will be ease to lose whole limbs and even far less serious and far more have several surgeries as only a mundane. However, the more tiny segment of diseased tissue uncommon and horrific afflic- has to survive to restart the infections do tend to be far more in- tion. teresting, which is why I’ve de- cided to write this column about Many strains of bacteria can cause the most obscure and gruesome this condition as most produce diseases, which you might not similar by-products, but it is im- have even known existed. hour the site of initial infection degree when the diseased tissue portant to note that it is very rare is incredibly painful and has has to be removed. for a bacterial infection to mani- begun to swell. Soon the victim I’m guessing most people read- fest itself as ‘flesh eating bacte- suffers diarrhoea and vomiting ing this will not know what I ria,’ the majority of the time the as the area of inflammation As the disease progresses so mean when I talk about necrotiz- infection will cause a less serious worsens, often with the skin quickly and is at first very simi- ing fasciitis but will instead condition. The worst form of the turning violet and blisters form- lar to any other minor bacterial know it by another, more collo- disease is now caused by MRSA ing. By this stage, only several infection any treatment must be quial name; ‘flesh eating bacte- (Methicillin Resistant Staphylo- hours since contamination, the fast and effective. The appropri- ria.’ This rare condition begins coccus Aureus), which as you’ll swollen tissue is decaying rap- ate antibiotics must be deter- with an often unnoticeable infec- all know from our previous issue, idly and the patient experiences mined quickly as they take time tion that infiltrates the skin at a is resistant to most antibiotics and a high fever as the bacteria over- to act on the infection, time the site of trauma; a small paper cut therefore can cause an even more whelm any ineffectual immune victim does not have. By the for example will be enough. The prolific form of this issues grue- response. There is a 30% mortal- time they have began to control infection then spreads at the fast- some and obscure ailment: ne- ity rate and most of the survivors the spread of infection, through est rate of any disease; within an crotizing fasciitis. suffer disfigurement to some the deeper layers of the skin and

(continued from page 1) ciable, with bats grooming each Hopefully this shows that despite other and, when an individual has the controversy surrounding the failed to feed, the regurgitating of vampire bat, stemming from its Vampire bat colonies, in old blood from mouth to mouth to name, it is one of the most highly wells, hollow trees, caves and prevent starvation. buildings, typically number just a evolved and misrepresented of single male and around twenty After a feed, due to the large creatures females and their offspring, amount of protein consumed, though have been known to num- vampire bats excrete extremely ber in the thousands. They will concentrated urine, controlled by The vampire bat is often roost with other species of a number of specialised hor- bat (which has created problems mones. Vampire bats mate all found in areas of when beneficial fruit bats have year round but usually have only Central and South been killed in Latin America by one offspring per year, as their attacks on vampire bat roosts). gestation period is six-eight America These colonies are extremely so- months. Page 3 Life. Issue 6 Corpus Amygdaloideum

By Edmund Bradbury works. This conscious, logical area of the The amygdalae are neural structures con- brain is not used to working out facial ex- nected to the hippocampus and the hypo- pressions, explaining the decrease in correct thalamus. These small areas of the brain are answers. mainly responsible for emotional processing. More recently, research has shown the Most people’s amygdalae are automatically amygdalae to also play a role in our under- and naturally developed to recognise a huge standing of fear. range of emotions, however, in the case of

an autistic person, they must learn to recog- People with autism often have certain skills nise these emotions artificially. Researchers which are more highly developed than the have developed an “encyclopædia of emo- general population, such as advanced tions” which can be learnt and memorised, mathematical skills. However, autistic peo- to help autistic people to improve there so- ple often seem emotionally remote or dis- cial skills. connected socially. If we look at fMRI One of the amygdala’s more intriguing (Functional Magnetic Resonance Imaging) properties, is its ability to store fear memo- scans of people trying to work out how peo- ries. In the 1980s, Professor Joseph LeDoux ple around them are feeling, using facial did an experiment on the fear response in reaction from the amygdala. Then the con- expressions, we see that the amygdala shows rats. A tone was played and simultaneously a scious part of the brain would think of an increased activity. People with autism show shock was delivered to the rats. Even from explanation for the stimulus: “bear!”. dramatically reduced amygdala activity, the first pairing of tone-shock the rats started which may account for the ‘social discon- to fear the tone itself. He then tried to find nection’. where in the brain this fear memory was The fact that the memories are simply fear responses, can lead to completely irrational being created. Starting with the auditory cor- fear, or phobias. Someone who has had a In colloquial terms, the amygdala could be tex he removed parts of the rat’s brain until bad experience of, say a bird as a child may described as the “gut feeling centre” of the they could no longer learn to fear the tone. have a fear response upon seeing a bird, brain. When people take the ‘eye reading’ After much research he found, using a tracer simply from the memory stored in the test, (a test involving showing pictures of dye, a connection to the amygdala. When the amygdala. Even if the bird seen was safely peoples eyes, and the subject must deter- amygdala was removed from the brains of caged, meaning that the person is com- mine the emotion of the person in the pic- the rats, they could not learn the fear re- pletely safe, the amygdala would still trigger ture) it is often found that if people answer sponse. a fear response, despite the conscious part the questions quickly without thinking too of the brain knowing that the person was deeply about each question, and trusting The memories stored by the amygdala, are not at risk. there “gut feeling” they achieve higher re- very basic, they do not contain the all the sults. This is because the “gut feeling”, trig- information stored by traditional memories, gered by the amygdala is working all the but simply a stimuli-fear pairing. The study of the amygdala has helped us to time in social situations without us noticing understand the many different layers of its actions. We are effectively, from children, For instance, if one were walking in a forest interpretation or “thought” the brain is ca- trained to recognise emotions from facial and one saw a sudden movement to one pable of; the logical conscious areas can be expressions quickly. The more we think side, one would not think, “bear!” and then influenced by the more primitive, subcon- about the problem in the ‘eye-reading’ test, feel fear, one would feel fear first. Adrenaline scious elements of the brain, such as the the more the frontal lobe of the brain would be released; this is all the triggered amygdalae.

classed as a Class 1 Carcinogen. Dimer- Science In Crime caprol is a drug that was developed to com- bat arsenic poisoning. To test for Arsenic By Oliver Curwen poisoning, one must dissolve any of the The Case: Dandelion Poisoner infected person’s tissue in Hydrochloric acid During the year 1922, Arthur Martin fell ill and then place a copper strip in the mixture. because of arsenic poisoning. In the early If a dark grey coating forms on the copper 20th Century, one could buy arsenic as a strip, Arsenic is present. means of killing dandelions. Obviously, one My Score for this poison: 9/10. It is not could not buy enough to kill a human. One immediate, giving the attacker time to run; man, Major Armstrong, however had the time it takes to release symptoms is ap- bought enough arsenic and kept it, to take proximately two weeks. Arsenic is expensive out his company’s opponents. He was even- and only found in Mexico, The Andes, Rus- tually arrested and executed. Arsenic is an sia and The Alps. element on the Periodic Table and is also Page 4 Life. Issue 6 Four Limbs Extra By Nicholas Weise twin, in order that she live a full and normal life. Without the operation, she would not India, 2005. On the eve of Diwali a girl is have been expected to reach her teenage born to a rural Indian family who live in years. The operation took place in Novem- Bahir. But this is no ordinary girl. Whereas ber 2007. It had been estimated that the most people have two hands and two feet, whole operation would last for 40 hours she has four of each giving her eight limbs with 30 medics working on the child, but in in total. As she was born on the night when reality it lasted only 27 and was a complete all Hindus celebrate the benevolence of the success. It involved removing the extra Goddess Lakshmi (who is also believed to limbs and duplicated organs of the headless have four arms) she is named after the deity. twin from Lakshmi and re-angling her blad-

der and pelvis so that she would be able to Last year in October Lakshmi Tatma, the walk on her own two legs. It was also neces- girl with eight limbs, celebrated her second sary to transplant the single, shared kidney birthday. However, unlike the other children to Lakshmi from her undeveloped sister. her age, she could not walk as she had control over her uppermost arms and legs but Several people had been opposed to the not the lower pairs. Realising that her extra at the pelvis), however in this rare case the operation believing that this girl was the arms and legs would hinder her motor skills, second and until then unrecognised twin had reincarnation of a Hindu Goddess. In her her parents took her to their local doctor no head leaving just most of the ribcage and old village people used to queue to receive who referred them to specialists at a nearby four extra limbs. blessings from her. But her parents were more interested in her living the happy and hospital. Here it was discovered that Lak- shmi was not one child, but two. She was normal life, which should now be possible another example of conjoined twins (joined It was deemed necessary, that Lakshmi un- for her. dergo an operation to separate her from her Invasive Species By Nick Pepper There would have been no So, what is an invasive species? problem, were it not from an Has it come from outer space? unseen danger in the grey squir- Is it going to overthrow earth? rels. They carried a virus in Fortunately the answer is no. their fur, a virus to which they An invasive species is a species were not susceptible, but which that has been imported from was absolutely lethal to the grey another country that would squirrel’s neighbour, the red otherwise be out of the species’ squirrel. It was so damaging range. This is a major threat to that even today there are only biodiversity; it is second only to 160,000 red squirrels left in the habitat destruction and as such UK. The grey squirrels also had has caused governments inter- another impact, this time on the nationally to try to reduce the timber industry. They would risk, that the invasive species strip the bark from broadleaved cause. In the next few lines I and coniferous tress. The dam- will tell you why. age was valued at around world. This really poses a prob- vent foreign species entering £10,000,000. lem when the foreign species their countries. A classic exam-

Problems of invasive species enters the ecosystem of its new ple of extinctions as a result of home. In their new habitats the invasive species is that of the A simple walk through Manor Non-native species entering new residents can out compete grey squirrel. Park today will reveal the extent countries was not a problem other organisms and dominate of which the problem has until the modern age. Before the food chain. This can cause spread. There are millions of natural barriers like the sea, The grey squirrel all sorts of problems; the sever- mountains and inhospitable grey squirrels in Britain at the ing of the food chain means The grey squirrel was originally climates stopped species from moment and despite being easy that some species can become introduced to 30 different areas spreading to habitats unsuited to catch, the problem has not extinct and habitats uninhabit- of the UK, it was imported for them. Now, in the jet set and is unlikely ever to be able for others. This is why from the USA and Canada and age a species can find itself solved. governments are keen to pre- adapted well to its surround- transported to anywhere in the ings. Page 5 Life. Issue 6 Marfan- The Tall Man’s Syndrome

By Ali Jawad nective tissue which are in the Have you ever wondered why ligaments, joints and the structure some people are freakishly tall that connects your heart, eyes, with very extensive arms and fin- lungs and bones throughout your gers? The answer maybe that they body. This means that these struc- suffer from Marfan syndrome: an tural proteins used are far weaker incurable, genetic disorder of the than they are meant to be. Now connective tissue mainly distin- imagine a heart under stress, guished by a tall stature, elongated pumping vigorously, how far can limbs and having cardiac and oph- it go until the connective tissues thalmic complications. Studies on your heart tear? show that 1 out of every 5,000 people in the world have been Nevertheless it’s not all doom diagnosed with Marfan Syndrome. and gloom, there are some very The condition can affect anyone effective treatments, but each of regardless of gender, ethnicity or them are aimed at any one of the age however it is still seen as a symptoms. Doctors advise victims relatively rare disease. of Marfan Syndrome to take regu- lar eye tests so that the doctor can Most people with Marfan Syn- prescribe glasses and contact drome are taller than normal and lenses which very much improve the quality of life. Orthopædic from increasing in severity all by knowledge or a sufficient enough males can reach at least 6’5’’ while continual assessment and exami- health care system to measure most females are taller than 6’. surgeons also check the curvature of the spine who may prescribe a nation. how many people are actually Nonetheless there are some truly suffering from this fatal and dangerous symptoms which pre- removable brace to stabilize the There are numerous ways to di- unique illness. MFS is, in spite of dominantly relate to the heart and spine, and additionally, cardiolo- agnose someone with Marfan eyes. The problem is that suffer- gists make several scans and can Syndrome, the physical effect is everything, quite a complex dis- ers have a defect in the FBN1 even prescribe beta-adrenergic quite evident and through close ease and this is illustrated by the gene which produces a vital pro- blockers which prevent aortic inspection doctors can confirm fact that even now the world of tein called fibrillin. This protein is dilation. As you can see the qual- that a case is in fact Marfan Syn- medicine still cannot find a cure ity of life can be improved signifi- drome. However many develop- absolutely crucial for the forma- for this extraordinary human de- cantly and cases can be stopped ing countries still do not have the tion of elastic fibres in your con- fect. Molecule of the Month

response to external stimuli, and into a form that is easily accessi- ing forced to undergo apoptosis. Nitric Oxide then carry it to a conclusion ble to macrophages. These cells Mutant lymphocytes could attack themselves. But apoptosis is ex- are a type of phagocyte specifi- healthy cells, and this is thought tremely important in keeping the cally responsible for clearing up to be what causes some degenera- body healthy. the remains of suicidal cells. tive diseases.

By Richard Morris When the cell receives the cor- This process has many impor- Nitric oxide is one of the chemi- It’s such an amazing molecule; rect signals telling it to undergo tant applications. In the immune cals that regulates apoptosis. It it’s back for a second time! As apoptosis, a certain type of en- system, cells known as T- has various effects depending on well as its role in immune re- zymes known as ‘capases’ are lymphocytes are responsible for the dosage and the cell type it is sponses, nitric oxide also helps in activated. These begin to break triggering apoptosis in damaged directed at. It has various different apoptosis, or programmed cell down key components of the cell, or infected body cells. This effects. In some tissues it will death. such as DNA, repair enzymes and helps to fight viral infections, induce apoptosis in the cells, proteins in the cell structure. In and prevents cells with cor- while in others it will inhibit it. turn, ‘DNases’ are activated, rupted DNA becoming cancer- This means it could have potential Apoptosis may seem a strange which begin to break up the DNA ous. T-lymphocytes themselves in treating some degenerative thing for an organism to develop, in the cell’s nucleus. Finally, the are ‘screened’ before they enter diseases, as these are thought to the controlled suicide of its own cell shrinks and deforms as its circulation, with potentially dan- be caused by too much apoptosis, cells. Cells begin this process in structure breaks up. It wraps itself gerous mutant lymphocytes be- leading to degeneration in tissues. Page 6 Life. Issue 6 Sport Science - Steroids

By Alex Grimes for is that anabolic steroids main- Anabolic steroids are a drug used tain male characteristics. They to help people exercise and to can deepen voices and increase enhance the size of their muscles. the growth of body hair. This is Steroids are not illegal drugs due to the virilizing and andro- (laws change from country to genic properties of steroids. Al- country) however almost all though this article is focused on sports have banned the drugs, sport, there are medical uses for calling them an unfair advantage Anabolic Steroids such as bone and cheating. However steroids growth and increasing appetite. can have some severe side effects. There are many different However, as mentioned earlier types of anabolic steroids, one anabolic steroids are banned in being testosterone. most sports, including football, tennis, cricket and athletics. Use Anabolic steroids are also of drugs such as this in sport can known as anabolic-androgen result in players being banned. blood pressure and a change in growth of breast tissue on males, steroids (AAS). Many people An example of this was the 400m the balance of cholesterol. They temporary infertility in males and think of steroids as muscle build- world champion Christine Ohu- may increase the amount of bad increased body hair on women. ruogou who was banned for sev- ing drugs. This is in a way true, cholesterol, also known as LDLs what they actually do is increase eral years previously due to miss- (low density lipoproteins) and a In conclusion anabolic steroids protein synthesis which results in ing drug screenings. decrease in good cholesterol, also help people in sport. However a build-up of cellular tissue, in known as HDLs (high density they are not allowed in most ma- particular muscle tissue. This lipoproteins). There are also sev- There are many side effects of jor sporting bodies as it is consid- means it is easier for people to eral more illnesses caused by anabolic steroids. A lot of these ered cheating. There are also grow larger muscles. Another anabolic steroids; however there are gender specific. The two many severe side effects that can things that people use steroids are two many too list. Gender main side effects are increased specific side effects include: be fatal, in the worst cases.

That’s Life By Joe Robinson A1. It is not the blue whale, in fact it is a giant

mushroom. The honey fungus mushroom is ex- Q1. What’s the largest living thing on Earth? tremely common and grows on rotting wood. In the Malheur National Park in Oregon there is a

honey fungus which covers 890 hectares! Most of Q2. What’s the biggest thing a whale can this is underground and it is believed to be between swallow 2000 and 8000 years old. a) A large boat b) A small car A2. C. A grapefruit. The whale’s throat has the c) A grapefruit same diameter as its belly button, about the size of an average dinner plate. c) A sailor you by a new editing

Q3. How many legs do centipedes have? A3. Not 100. The centipede closest to having a hundred legs had 96. The majority of centipedes Q4. In the world, what country do most tigers have an odd number of paired legs and this can live in? range from 15 to 191 pairs.

Q5. How long do your hair and fingernails A4. The USA, in captivity. grow after death?

A5. Hair and fingernails do not continue to grow after death. It is simply the skin of the body shrink- ing giving the appearance of longer hair and finger- Life—Now presented to team, with thanks to Jack Shepherd, for his ef- forts in the past year. Please keep sending in your articles to Chris Slade at [email protected] nails.