Teddies Talks Biology - Issue 9

Creative Writing by Mashia Jaafari—UVI

It was a nice day in the simplest sense; one of those days where you feel that nothing could go wrong, as if the golden glow of the sun or the melodic chirping of birds could somehow protect you from the harsh realities of life. Midday approached and the park became increasingly crowd- ed, the thick patches of grass disappearing under a façade of colourful picnic blankets and sun bathers who hoped they could use this opportunity to perfect their pre - summer tan. Numerous picnic baskets, all filled to the rim with an assortment of delicacies, were scattered across the land and in one of those baskets in particular there was an egg. A simple brown egg, common and unspectacular, appearing completely harmless to the humans that were unaware of the fam- ily of bacteria frantically multiplying within it. This seemingly normal egg had not been cooked properly; the hasty rush in the morning - caused by the intention of getting an acceptably close parking space - had meant that it was taken out of the water prematurely, before the high tem- peratures had the chance to completely eradicate this population salmonella bacteria.

Finally, as the sun asserted its unquestionable dominance in the centre of the sky and the surrounding plants began tran- spiring more and more quickly, it became universally clear that it was time for lunch. In response to this supposed sign of na- ture, a large hand eagerly swung open the lid of the picnic basket, expertly extracting from it none other than the afore- mentioned egg. It sat comfortably in the man ’ s rather large hand, which had by now crushed and removed the last of the coarse remnants of the egg ’ s harsh exterior. The man careful- ly guided it into his mouth and chewed slowly, enjoying the fa-

miliar taste that he was accustomed to from his usual breakfasts. Once he felt that the chewing sufficed and the protease enzymes in his saliva had successfully done their job, he swallowed. The epiglottis snapped shut in a rapid reflex action and the components of the egg moved down the oesophagus, being nudged down faster by the drink of water the man took to refresh himself. The bacteria were in. This concoction of protein and fat reached the stomach and was greeted by the unforgivingly low pH of hydrochloric acid. Usually at this point any bacteria would have fallen to the mercy of this acid, but not these bacteria. They have developed adaptive mecha- nisms that allowed them to survive the acidic conditions of the stomach and happily passed into the man ’ s intestinal tract. Once in the small intestine these salmonella bacteria felt at home, quickly and relentlessly invad- ing the lining of the small intestine. The bacterial endotoxins quickly went to work, inducing symptoms of the disease such as vomiting and diarrhoea. As the man woke up the next morning, his awful sunburn was not the only thing troubling him; he felt nauseous and a terrible urge to go to the toilet. Luckily, the bathroom was not far away, and he managed to drag himself onto the toilet before things got messy. As relieving as that was, even better was the fact that a non - specific response was even closer. Mast cells and basophils detected the polysaccharide part of lipopolysaccharide endotoxins and quickly released histamines. These histamines induced vaso- dilation leading to a local increase in temperature. They also caused the walls of the capillaries in the lining of the small intestine to become leaky by making the cells separate, thereby allowing some phagocytes into the area. Soon after this, the hypothalamus raised the body temperature to 38 degrees inducing a fever. The man felt very ill indeed, but this was even worse for the bac- teria – their division slowed while the phagocytes could work more efficiently. As soon as the phagocytes entered the infected tissue, they engulfed these treacherous pathogens, enclosing them into a phagosome which then fused with a lysosome. Fortunately, the hydrolytic enzymes within the lysosome brought the engulfed bacteria to their doom.

Teddies Talks Biology I Issue 9 I June 2021

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