Why Our Eyes Water When Cutting Up an Onion

Many people wonder why onions make their eyes water just by chopping it up. They are related to garlic and chives. When cutting up an onion, it makes us shed reflex tears. Reflex tears are tears that result from an irritation in the eye by a foreign particle or from irritant substances. Their job is to wash out irritants that may have come into contact with the eye. As you cut an onion, you cut through the cells that contain a sulfur compound. This compound turns into a bad smelling gas. Since the substance in the onion is so strong, the eye treats it as an irritant. The onion activates nerve endings in the cornea, which communicate with your brain. The cornea is a dome shaped, transparent tissue protecting the iris and the pupil. From there, the brain sends a message to the lachrymal gland. The lachrymal gland’s job is to release tears and flush away the irritant. A theory to stop your eyes from watering when you cut up an onion is to chew gum. Some people even say that if you move your cutting board near the sink and turn on the water this will stop your eyes from stinging too.

Video

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Loggerhead Sea Turtle

The Loggerhead Sea Turtle has a reddish-brown, leathery skin color. Its top shell is heart shaped, and its bottom shell is a pale yellow. These turtles weigh about 250 pounds, and they are 28 to 39 inches in length. Many of these turtles can be found in any ocean, except in the polar regions. Their habitats include: oceans, coasts, reefs, bays, and they nest on sandy beaches. Many fishers accidentally capture these types of turtles in their fishing gear, and people develop buildings on their nesting areas. This is why they are an endangered species. One interesting facts about the Loggerhead Sea Turtle is that is the the largest hard shelled turtle in the world. Whelks and conch are the food for these turtles. The reason they can eat these hard sea creatures is because the Loggerhead has a very powerful jaw. Mainly, other sea animals do not target this type of turtle, except for the killer whale. Nekton is the category of ocean life the Loggerhead Sea Turtle would fall under, because it can swim or float anywhere. These turtles can hold their breath underwater for an estimate of one hour. When they are pregnant, they stay closer to the shore line, so they can be ready to give birth on the sandy beach. Loggerheads are in the neritic ocean zone, they stay close to areas with ocean currents, so they can float. Their main way of transportation is by floating along with the current. The reason I picked this turtle is because I thought it was amazing that they could travel up to 15 miles per hour in the water. Also, I thought it was interesting that 14,000 females nest in the southeastern U.S. each year.

http://kids.nationalgeographic.com/kids/

Have you ever heard of an Axolotl?

The Axolotl is one of the most obscure animals in the world. They are part of the salamander family. This species is in danger of becoming extinct, since they are only native to two lakes. These two lakes include Lake Xochimilco and Lake Chalco in central Mexico. One of the lakes has been drained by humans to prevent flooding. This rare animals is currently on the International Union for Conservation of Nature's annual Red List of threatened species. Many scientist keep these animals as pets because they are very easy to breed. An average mature axolotl ranges from the length of 15 to 45 centimeters. Coming out of this species head is a fin, and they also have external gills that they get when they turn older. They are carnivores and consume worms, fish, and insects. Axolotls main colors are pale pink and golden, with pink and black eyes. Locating their prey by smell, and then sucking it up into their stomachs is how they catch their dinner. The Axolotls are eaten by fish not native to the area, such as the African tilapia and Asian Carp. This species is sold as food in Mexican markets, and was a main ingredient to the Aztec diet.

http://www.axolotl.org/