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Yes ! It's that old riddle that sparked many arguments through years - was it the chicken or the egg that came first? It's a really tricky question because you need a chicken to lay an egg,but chickens come from eggs,leaving us with this feathery life that apparently has no starting point. Thankfully,there is no need to keep brooding over this forever. This is a riddle which we can unscramble with the principles of evolutionary biology. Let's get cracking. The first were the chicken eggs. But wait - weren't there some scientists who claimed that the chicken came first? This claim came from some researchers studying how chicken eggshells form. Eggshell is mostly made from Calcium Carbonate (CaCO3). Hens get their supply of calcium for eggshell production from dietary sources (calcium rich seafood shells,such as oyster). To form a shell,the calcium needs to be deposited in the form of CaCO3 crystals,and hens rely on specific proteins that enable this process. One such

Ugghhh COVID - 19 is everywhere rite now,killing milllions,not enabling students to go out and enjoy after board exams,not allowing them to eat ice creams and cakes.....What not has this COVID - 19 done to us? It came from a seafood and meat market in Wuhan,China and is now spreading throughout the globe at an increasing rate. So what is this corona virus? A corona virus is a virus found in animals,that is rarely transmitted to humans and when transmitted to a human,spreads from a person to another person. What are the symptoms of corona virus? It takes 2-14 days after exposure to the virus for symptoms to develop. Symptoms may include: 1. Low grade fever that gradually increases in temperature. 2. Cough 3. Shortness of breath. Those with weak immune systems may develop more serious symptoms,like bronchitis or pneumonia.  PREVENTION OF CORONA VIRUS: 1. Maintain distance from people who are sick and avoid meeting in large groups. 2. Cover your cough with a