字幕列表 影片播放 列印英文字幕 It's AumSum Time What is special about a giraffe's heart? It beats only when someone special is around. No. Giraffe is the world's tallest animal. Its neck is almost 6 feet long. This means a giraffe's brain is six feet above its heart. Making it difficult to pump blood to the brain against gravity. Now, The special thing about giraffe's heart is that it remarkably pumps blood all the way to the brain. Overcoming the gravity. How? Giraffes have a big heart with thick walls. It can weigh up to 25 pounds. That is equal to 50 human hearts. Due to this big heart and thick walls, a giraffe's blood pressure can be two times higher than human beings. Helping it defy gravity and pump blood to the brain. Topic: Metals and acids. Why is curd not stored in copper containers? Hey wait. What are you doing? Don't eat that curd. It was stored in a copper container. Please listen. Fine, then bear the consequences. I had warned you. Do you know why this happened? This happened because curd contains lactic acid in it. When curd is stored in containers made up of metals like copper or brass. The lactic acid present in it. Reacts with the metal and forms metallic salts. These metallic salts are harmful. They make the curd unfit for human consumption. Therefore, to prevent metals from reacting with acids present in food. The metal containers are coated with a thin layer of tin. Tin is also a metal. However, It does not react with acids as rapidly as other metals do, thus keeping the food in the container safe. Topic: Dandruff. Why do we get dandruff? Tearing of pages. No. Dandruff is a condition in which our scalp sheds skin cells in the form of white flakes. A yeast called Malassezia globosa, is one of the mostly accepted reasons for causing dandruff. What a classy name it has. Indeed. Malassezia globosa is naturally present on our scalp. It feeds on sebum and releases oleic acid. Now, some people are sensitive to this oleic acid. When it penetrates into the upper layers of their skin, it causes inflammation. Hence, in response to this inflammation, their skin sheds a large number of skin cells at a higher rate. These cells then join together forming white flakes, thus causing dandruff. Why do newborn babies get jaundice? I don't know. Each red blood cell in our blood lives for about 120 days. Once it gets old, it is broken down into smaller components. One of them is bilirubin. Bilirubin is a yellowish waste compound. Hence, Our liver removes the bilirubin from our blood which is then excreted by the body through intestines. However, if bilirubin is not removed, Its level in the blood starts to rise and excess bilirubin begins to get deposited in the body tissues. As a result, the skin and white areas of eyes appear yellow, thus causing jaundice. Now, a newborn baby's liver is still developing. Thus, it cannot efficiently remove bilirubin from blood, thus causing it jaundice. Usually, jaundice is normal in babies and will disappear in some days as the baby grows. However, if it doesn't disappear, we should immediately consult a doctor. Why do cats have vertical pupils? Wait. I'll explain. A pupil is an opening in the iris which regulates the amount of light entering the eye. Now, not only cats but also predators like crocodiles, snakes, etc. have vertical pupils. Since these animals hunt in day as well as at night. Vertical pupils allow a greater control of the amount of light entering the eye. Greater than my round pupils? Yes. Round pupils in humans can change their area by a factor of 15. While, vertical pupils can change their area by a factor of 135. Hence, on a bright day, Predators can turn their pupils into narrow slits, allowing less light to enter. Thus, preventing their eyes from getting dazzled. Also, when there is less light or in near-darkness, the vertical pupils expand to a strikingly large extent. Allowing more light and thus, helping the predators to see and hunt more preciously.
B1 中級 美國腔 長頸鹿的心臟有什麼特別之處?| 長頸鹿的心臟有什麼特別之處? (What is Special about a Giraffe's Heart? | #aumsum) 6 1 AumSum 發佈於 2021 年 01 月 14 日 更多分享 分享 收藏 回報 影片單字