Topic: Red eye effect. Why do my eyes glow red in photos? Because there is a devil hidden in you. Stop bluffing. Alright. I will explain. It happens because of blood vessels in our eyes and pupil. Pupil is a small opening whose size is adjusted by the circular muscle called iris. In bright light, the iris contracts making the pupil smaller, thus allowing less light to enter into our eyes. In dark, the iris relaxes making the pupil larger, thus allowing more light to enter and also exposing the blood vessels in our eyes. Hence, when we take a photo in such a dark environment, the flash of light from the camera floods into our eyes at once. Some of this light gets reflected from the blood vessels onto the camera before our iris can contract , making our eyes glow red in photos. Topic: Pressure. Why does popcorn pop? Because popcorn is a pop dancer. No. There are a variety of corns such as field corn, sweet corn and popcorn. However, popcorn is the only corn that pops. Why? Does it have some magical powers? No. There are three things in a popcorn seed or kernel that work together to form a perfect popcorn. Those are an impermeable shell called pericarp, right water content and starch. When we heat popcorn kernels, the water inside them forms steam and starts to expand, while the starch turns into a gel-like substance. Being enclosed, the expanding steam applies pressure on the shells. Eventually, when the shells cannot hold the pressure, they burst open releasing the steam and gel. When this gel comes in contact with air, it rapidly solidifies forming fluffy popcorn. Topic: Human Nose. Why does spicy food make your nose run? Because it is not that strong to make me run. No. Our nose consists of tiny hair and a sticky substance called mucus. Can I use this mucus to stick my broken vase? Gross. Please don’t do that and listen. During breathing, the hair and mucus trap harmful substances, thus prohibiting them from entering deep inside the body. Now, spicy food items like chili, mustard, horseradish and wasabi contain chemicals called capsaicin and allyl isothiocyanate. When we eat such food items, the capsaicin and allyl isothiocyanate travel through the pharynx and reach our nose. Here, the chemicals activate the heat sensing receptors, thus causing inflammation in our nose and irritation of the mucus. Hence, as a defense mechanism more mucus is produced in our nose to get rid of these chemicals, thus making our nose run. Topic: Ignition Temperature. Why is it easier to burn dry leaves but not green leaves? Because it is easier to spell dry than green. No. It is because of ignition temperature. Ignition temperature is the lowest temperature at which a combustible substance starts burning. Now, green leaves have moisture or water in
them. Wow. So, can I use them as water balloons? Please listen. Water has a property of absorbing a huge amount of heat before evaporating. Hence, when we try to burn green leaves, a large amount of heat is required to first evaporate the water. Then to reach the ignition temperature of leaves, thus not allowing the leaves to catch fire easily. However, dry leaves don’t have water in them. Hence, they don’t need much heat, making them burn easily. Topic: Thermoregulation. Why do we sweat? It is a natural way of our body to take a bath. No. Sweating helps in thermoregulation. Thermoregulation is the process by which organisms maintain their internal body temperature. Now, the internal body temperature of a human is about 37 degrees Celsius or 98.6 degrees Fahrenheit. Our enzymes and hormones work best at this temperature. Hence, thermoregulation is very important for us. Well, If you ask my opinion, chocolate syrup is very important for me. Just listen. On a sunny day or during exercise, when our body temperature increases, our sweat glands produce sweat. This sweat is about 99% water. Water is a very good heat absorbent. It absorbs much of our body heat and evaporates into the atmosphere, helping us lose heat and thus maintaining our body temperature. Topic: Forced Vibrations. Why does a guitar have a hollow box? To keep clothes while traveling. Not at all. Wait. I will explain. Whenever we strike an object, it vibrates. Sometimes, these vibrations influence other
objects to vibrate. The vibrations which take place under the influence of an external periodic force are called forced vibrations. So, whenever I see delicious food, my stomach starts to vibrate. Is this a type of forced vibration? Please concentrate. A guitar has a hollow box which holds quite a huge volume of air. Now, when we strike its string, it starts to vibrate. These vibrations influence the air in the hollow box, producing forced vibrations in them. Now we know that vibrations in air produce sound. Hence, as a huge volume of air is vibrating, the sound produced is louder. Topic: Human Bones. How does a bone heal? Simple. By a bandage. No. Bones are one of the most important parts of our body. They not only provide structural support but also produce red blood cells. What? Our bones produce red blood cells? Absolutely. Hence, when we crack or break a bone, it is very important to heal it. In the healing process, cells called chondrocyte produce collagen which forms cartilage. This cartilage bridges the gap between the broken bones, thus producing a soft callus. Then, special cells called osteoblasts create a hard bony callus using collagen and minerals like calcium and phosphorus, thus forming our new bone. However, this new bone is irregular in shape. Hence, cells called osteoclasts start remodeling the bone, resulting in the formation of bone similar to the original shape. Topic: Human Tears. Why do onions make you cry? Because they cannot crack a joke. No. Onions consist of amino acid sulfoxides. When we cut an onion, millions of onions cells rupture, releasing the amino acid sulfoxides along with some special enzymes. These special enzymes react with amino acid sulfoxides to form a chemical called Syn-propanethial-S-oxide. This chemical is volatile, that is, it easily evaporates at normal temperature, forming a gas. When this gas reaches our eyes, it reacts with the substance that keeps our eyes lubricated and forms mild sulfuric acid. What? An acid in my eyes. Absolutely. This sulfuric acid gives us a burning sensation. Now, in order to wash off this acid, our lacrimal glands produce a disinfecting liquid. But when our eyes cannot hold any extra amount of disinfecting liquid, it starts to fall down, making us cry. Topic: Distillation. Is distilled water safe to drink? How would I know? Am I a detective? Alright, Alright. I will answer it. Distilled water is obtained from distillation. In distillation, the impure water is first heated, thus converting water to vapor. Then this vapor is condensed by cooling, hence converting vapor back to liquid water. By this process, the impurities remain behind, giving us pure distilled water. Now, even though distilled water is pure, some doctors say that we should not drink it for a prolonged period of time. So, can I take a bath with it? I haven’t bathed since last Sunday. Gross. You are just impossible. It is generally recommended to avoid drinking distilled water for a long period because along with the impurities. The minerals required for the proper growth of our body are left behind during distillation. Topic: Caffeine. How does coffee keep you awake? By throwing an overnight party. No. When we perform our daily activities like thinking and playing, a by product called adenosine is produced. Adenosine slows down the brain activity. But how? In our brain, there are adenosine receptors
which are perfectly molded for this adenosine. When the adenosine binds to these receptors, it activates them, causing to slow down the brain activity and thus making us feel sleepy. However, drinking coffee keeps us awake and we don’t feel sleepy. This is because coffee contains a drug called caffeine which after digestion reaches our brain. Caffeine is structurally similar to adenosine. Being similar, caffeine binds to the adenosine receptors and thus blocks the adenosine from binding. Hence, as adenosine does not bind, our receptors don’t slow the brain activity. As a result, we remain awake.