Topic: Ear. How do ears help with balancing? They really do. You don't believe me. Ok. Can you play a guitar and walk at the same time? How do you think you are able to maintain
your balance? Do you know why you can't balance yourself anymore? Wait, I will tell you. This happens because there is a connection between our ears and body balance. Our ear consists of 3 parts, outer ear, middle ear and inner ear. Our inner ear works in sync with our eyes and muscles, helping us maintain balance. While we are doing various activities. The inner ear consists of three semicircular canals called superior semicircular canal. Posterior semicircular canal and lateral semicircular canal. The three semicircular canals are arranged in three different positions. Each of these canals has a fluid called endolymph and hair cells called cilia at the base. Whenever we move our head, the fluid moves. Resulting in the movement of the cilia as well. When the cilia moves, it sends signals to the brain informing which direction our head has just moved in. Each canal has different functions as per the movement of our head. When we move our head up and down, the superior semicircular canal helps our brain to understand the yes motion. When we tilt our head towards our shoulders. The posterior semicircular canal helps our brain to understand the tilting motion. When we move our head from side to side, the lateral semicircular canal helps our brain to understand the no motion. It was too complicated, right? Ok, don't worry about it. Relax. Why don't you go on a merry go round ride? Hey. Why were you not able to maintain your balance? This is because when you sat in the merry go round and started rotating. The fluid in the semicircular canals also started to move. After a while, it was moving at the same rate at which you were moving. However, when the ride stopped and you got down from the ride, the fluid was still in motion due to inertia. Hence, even though you were not moving, the moving fluid gave your brain a false information telling that you are still in motion. Thus, you were not able to maintain your balance. Topic: Eyes Why do we have two eyes instead of one? You don't know? Ok. To understand this better, close your right eye. Now, are you able to see the table kept on your right side? You are not able to see it, right? Ok. Let me tell you why. Both our eyes work together and help us to see, judge and perceive a view accurately. Having two eyes provides us with a wider field of view. When both our eyes are open, we get a horizontal field of view of about 180 degrees. However, with only one eye open, we get a horizontal field of view of only around 150 degrees. We are unable to view around 20 to 30 degrees. Hence, we were not able to see the table when our one eye was closed. Hey. Did you know that our eyes see the same object from a slightly different angle? You don't believe me? Alright. Look at this object. Both your eyes see the object like this. Now, when you see only with your left eye, the object will look like this. While, when you see only with your right eye, the object will look like this. Our eyes send these two slightly different images to the brain. The brain blends or combines both the images to make a three dimensional image of the object. Hey. But what is the use of a three-dimensional image? A three dimensional image helps us to understand how far or how near an object is from us. Facilitating better depth or distance perception. This means having two eyes enables us to judge the distance of the object or the depth at which the object is placed from us. Topic: Osmosis. Why is grass killed if salt is sprinkled on it? Hey. What are you doing? Don't eat the grass. Fine. As always, ignore me. See, I warned you earlier. Hey, Wait. You are making it worse. Don't do that. Look. You spoiled it totally. Alright. Don't cry. I will tell you why this happened. This happened because of a concept called
osmosis. Osmosis is the diffusion or movement of water molecules from a region of higher concentration of water through a semi-permeable membrane to a region of lower concentration of water. Do you think osmosis took place when we sprinkled salt on the grass? You are right. Normally, osmosis does not take place on a
day to day basis because the grass tries to keep the concentration of water same inside and outside. Its cells through the process of transpiration. However, when we sprinkled salt on the grass. The concentration of salt outside the grass increased and the concentration of water decreased. As a result, the water present inside the
plant started flowing outside due to osmosis. Since most of the water flowed out, the grass drooped down and eventually, it died. Topic: Photosynthesis and Transpiration. Why is the upper surface of a leaf more green and shiny than the lower surface? Yes. It is. You don't believe me. Why don't you check it? The upper surface of a leaf is more green
and shiny. While, the lower surface is comparatively
less green and shiny. See, I told you. Do you know why? Ok. Let me tell you. You must be aware that chlorophyll, which
helps the plant to prepare food, is responsible for the green color of the leaves. But why is the upper surface more green than the lower surface? This is because the upper surface of a leaf
is more exposed to the sun as compared to the lower surface. Hence, to trap maximum sunlight, there is
more chlorophyll on the upper surface as compared to the lower surface. Hey. You forgot. You also wanted to know why is the upper surface of the leaf shinier, right? It is due to the process called transpiration. Transpiration is the loss of water from leaves, stems, etc. in the form of water vapor. Now, to make sure that the plant does not
lose a lot of water. The leaves are covered with a shiny, waxy coating called a cuticle. But being more exposed to the sun, the upper surface will tend to lose more water. Therefore, the upper surface of the leaf is
covered with a thicker cuticle as compared to the lower surface. Hence, the upper surface of the leaf is shinier than the lower surface. Topic: Respiration. Why is it not good to sleep under a tree at
night? Hey. You look so tired. Why don't you take rest here? No. Please don't sleep under that tree. It is quite harmful. See, you are not able to breathe properly,
right? Do you know why? Wait, I will tell you. This is because during the day, in the presence of sunlight, plants take in carbon dioxide. Release oxygen in the process of photosynthesis. However, they even respire simultaneously. In this process, plants take in oxygen and
release carbon dioxide. But the production of oxygen is more than
the production of carbon dioxide. Hence, if we sleep under a tree during daytime. We may get a good amount of oxygen, thus giving us a nice sleep. However, at night, plants do not perform photosynthesis due to the absence of sunlight. But respiration still goes on. Hence, as compared to oxygen, the proportion of carbon dioxide around the trees is more. Thus, if we sleep under a tree at night, we
may feel suffocated due to lack of oxygen. Moreover, inhalation of excess carbon dioxide is harmful to human beings. Therefore, it is not good to sleep under a
tree at night. Topic: Turgor Pressure. Why does a touch me not plant close? Hey. Don't touch that plant. You will get scared. See, you did not listen to me. Don't worry. Nothing to be scared about. Let me tell you more about this plant. This plant is called the Mimosa Pudica plant. Another name for it is 'Touch Me Not' Plant. When anyone touches this plant, it closes
its leaves with the help of pulvini. Pulvini are present at the base of each leaflet. They consist of cells filled with water. This water applies pressure against the walls of the cells. This pressure is called the turgor pressure. It helps the leaflets to stand upright. Now, when we touch a leaflet of the touch me not plant, specific parts of the plant release certain chemicals. These chemicals cause the cells in the pulvini to lose water. When water is lost, there is no more turgor
pressure. As a result, the cells collapse, resulting
in the closing of leaflets. Topic: Stomata. Why do water lilies have stomata on the upper side of their leaves? Don't immerse that plant completely in water. You don't have knowledge about anything. Water lily is an aquatic plant. So, I am keeping it totally under water. Yes, you are right. It is an aquatic plant, but it is not an underwater plant. Its leaves float on water. Don't lie to me. How can leaves float? Fine. Don't listen. Look. You spoiled it totally. Alright. Now don't cry. To understand why this happened, you need
to first learn about stomata. On the lower side of the leaves, tiny pores
called stomata are present. They help the leaves to take in carbon dioxide from air, during the process of photosynthesis. So, shall I place the plant upside down? No. We know that the leaves of water lilies float. Hence, if the leaves of water lilies would have stomata on their lower side. Then they would have been pressed against the water surface. As a result, the stomata would not be able
to take in carbon dioxide from air. Thus, the leaves of water lilies have stomata on their upper side. Where they easily get air and usually do not come in contact with water. Topic: Respiration. Why should we not overwater potted plants? It's because the water will overflow and make the floor dirty. No. Leaves of a plant take in oxygen from the
air present in the atmosphere. While, the roots, being buried in the soil, take in oxygen from the air present in tiny spaces of the soil. When we overwater a potted plant, the air
in the tiny spaces gets replaced by water. So, do the roots know how to swim in water? Please listen. As air gets replaced by water, the roots do not get sufficient oxygen to breathe and they begin to rot. This may adversely affect the growth of the
plant. Thus, we should always try to supply adequate water to the potted plants and not overwater them. Topic: Transpiration. Why do cacti have spines? Maybe they want to look like porcupines. Very funny. Spines help cacti to reduce transpiration. Well. I know all about vibration, but what's this
new thing called transpiration? Transpiration is the loss of water from ariel
parts, like stems and leaves, in the form of water vapor. These ariel parts contain stomata which allow water vapor to escape into the atmosphere. So, shall we tape the ariel parts so that
the vapor won't escape? Pay attention. In deserts, where cactus usually grows, there is scarcity of water. Also, due to high temperatures, the rate of
transpiration is very high. Thus, the leaves of a cactus have modified
into spines. Spines don't have stomata. Thus, the rate of transpiration is reduced,
helping the cactus to save water. Topic: Nerves. Why don't we feel pain when we cut our hair? Because if it would, then we would have got
angry on our hair dressers. You are just impossible. Wait. I will explain it to you. Inside our body, there is a network of nerves. These nerves help us to sense our surroundings and feel pain, touch, etc. by sending messages to the brain. So, do the nerves of my hair not know how
to send a message? No. Generally, the part of our hair above the
skin is made up of dead cells. It does not have any nerves. Hence, when we cut our hair, due to the absence of nerves, our brain does not receive any messages of pain. As a result, we don't feel any pain.
