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What Makes Something Alive? - Dr. Sanjaykumar Pawar Introduction: What Does "Alive" Mean? Have you ever wondered what makes something alive ? In simple terms, being alive means having life . When we say something is "alive," we mean it can do things that non-living things cannot do, like move, grow, or respond to the environment. Living things include all the animals, plants, and even humans like us. But have you ever stopped to ask, what really makes something alive? What qualities do living things have that set them apart from non-living things like a rock or a pencil? Movement: The Key to Life The most important sign that something is alive is movement . When we think of life, we often think of things that move around. But, movement doesn’t always mean running or jumping. Let’s explore how different living things move and how this helps us decide if something is alive. 1. Animals: Quick and Easy Movement Animals, including us humans, move in a variety o...

Understanding Chemical Reactions: Everyday Examples and Key Concepts - Dr. Sanjaykumar Pawar Let’s Begin: Real-life Situations & What They Show Us Let’s consider the situations one by one: 1. Milk is left at room temperature during summers . What happens? It gets sour or spoiled . Why? When milk is left at room temperature, bacteria in the milk start to grow and multiply. These bacteria feed on lactose, the sugar in milk, and convert it into lactic acid. This process is called fermentation , and it's responsible for the sour taste of spoiled milk. Chemical reaction? Yes – a chemical change occurs. The lactose (a sugar) is broken down by bacterial enzymes into lactic acid. The increase in lactic acid lowers the pH of the milk, which causes proteins to coagulate, leading to curdling. Clue: You can tell that milk has spoiled by a change in smell (a sour odor) and taste (a tangy, unpleasant flavor). Additionally, the milk may have a thicker consistency due to curdling, w...