Probably on a vine. I MEAN, AREN'T PLANTS SUPPOSED TO MAKE SEEDS?Yes, seeds are fruiting plants' means of reproduction. SO HOW ARE SEEDLESS FRUITS POSSIBLE?Well, the classic seedless fruit is the navel orange, so let’s start there. For those of you who need a refresher on basic plant biology, most fruits come from flowering plants. In a flower, there are two distinct reproductive organs: the pistil (female) and the stamen (male). When pollen, or plant sperm, lands on the tip of the pistil, or the stigma, the plant has been fertilized and can start producing seeds through fruit. This is why pollination is so important: without it, so many plants we depend upon wold cease to exist. WHAT DOES THIS HAVE TO DO WITH ORANGES?See, navel oranges will not reproduce with pollen that is genetically similar. The solution? A grove of trees that are quite literally clones. In fact, to our knowledge, there has only been one naturally occurring navel orange tree, which was created by genetic mutation. The tree, found in Brazil during the mid-1800s, was of great interest due to its sweet taste and seedlessness. The USDA then had two or three trees shipped to California, and the rest is history. Wait, IF THEY'RE SEEDLESS, HOW DO WE MAKE CLONES?Through a process called bud grafting. Basically, the top buds of one plant grow in the roots of another. It sounds weird, but it works. So, is that how seeDless watermelons grow?Alas, oranges do not give us the full story. In order to find this, we must turn to bananas. Bananas Don't have seeds?Not the kind we typically eat. (And if you think those little black specs down the center of your banana are real seeds, I have some news for you. This is what bananas with reproductive seeds look like. I highly doubt you can buy that at your local chain grocery store.) So how do we grow bananas then?Our favorite type of banana is the Cavendish. It has mutated to become a triploid. What in the world is a triploid?OK, time for some more basic biology. So, when most living things reproduce, they recieve two sets of genes: one from the “mother” and the other from the “father.” However, triploids have three sets of genes. That can't be natural.It is. While uncommon, Triploidy is a mutation that can even be found in humans. However, in the case of the commercial banana, you are not entirely wrong. Cavendish banana seeds originate from when a diploid banana, with two sets of genes, was crossed over with a tetraploid banana, which has four sets of genes. Since during reproduction the number of chromosomes is split in half, the modern banana now has three chromosomes, which makes it impossible to reproduce, rendering the banana sterile. But bananas are cloNes, too, right?Right. So Are Watermelons clones?Not exactly. You see, seedless watermelons are triploids as well. However, this was achieved by humans creating a tetraploid watermelon from the original diploid, and then mating the tetraploid with the diploid. However, cloning watermelons is not necessarily something we can do, so cross breeding is our main source of seedless watermelon seeds. So, how do seedless WATERMELONS GROW?Seedless watermelons are based on the idea that seedless fruits are better, which was introduced by the navel orange, and the use of triploids to render fruits sterile, which came from the Cavendish banana. However, despite these two fruits being reproduced with cloning technology, the seedless watermelon has yet to come this far. curiOus? Here's some more information:
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Toddlers. More specifically, toddler fingers. Ok, then how do toddlers' fingers get sticky?Um, have you ever met a toddler? They touch everything and refuse to/don't know how to wash their hands. that's not what i meant.Well, then what did you mean? How do adhesives work?Chemistry, but let's start with a definition to make sure we're all on the same page. According to DIN EN 923, a document that helps set standards for the adhesive industry, an adhesive is a non-metallic binder that acts via adhesion and cohesion. in English?Basically, an adhesive is something not metal that bonds with other materials. So, how does that work?In this interaction, there are two materials at play: the adhesive and the substrate. Typically, there are two substrate surfaces with an adhesive in between, since, you know, adhesives are made to stick things together. the plane of contact between the two is called the adhesion zone. There is then a transition zone, which sandwiches the cohesion zone, or the adhesive not in contact with the substrate. How does the adhesive bond with the Substrate?Well, everyday adhesives typically only form intermolecular interactions, which, while they do modify the adhesive's molecular structure, are quite weak and not very resistant to moisture. The bond energy for these interactions rages from 2 to 30 kiloJoules per mole, which is why we can pull off stick-on name tags without much effort. the other way adhesives work is through chemical bonds, an example being the bond between silicone and glass. Even though these bonds are stronger due to their resistance to moisture, they are less common. Their range of bond energy is between 100 and 950 kiloJoules per mole, which shows just how strong they are. additionally, the roughness of the substrate can make the bond stronger, although it is not a primary factor. This is referred to as "micro-mechanical adhesion". Is that what happens in the adhesive zone?Pretty much. So, what happens in the transition zone?Honestly, it depends on your adhesive. Some transition zones are large, while others are tiny. Some adhesives only have transition zones since they don't have a cohesion zone. The main point is that it is neither attached to the substrate nor is it cohesive, making it a transitory zone between the two. And in the cohesion zone?That's where there's cohesion. care to elaborate?Cohesion is the internal strength of the adhesive, or how it sticks to itself. This is often a tangled mess of a variety of bonds. Just like the adhesive zone, the stronger these bonds are, the stronger the adhesive is. So, what makes things sticky?Things are sticky due to the use of adhesive chemicals, which form bonds that contain three zones (adhesive, transition, cohesion) with substrate surfaces, often caused by the touch of a toddler. Curious? Here's some more reading!
An October candy that either tastes like fall or earwax, depending on who you ask. Ok, but what's in it?Pretty much just sugar. According to their website, Brach's classic candy corn contains “Sugar, Corn Syrup, Confectioner's Glaze, Salt, Dextrose, Gelatin, Sesame Oil, Artificial Flavor, Honey, Yellow 6, Yellow 5, Red 3.” What are confectioner's Glaze and dextRose?Weird stuff. Confectioner's glaze is 35% shellac. Shellac is a sticky substance, or resin, excreted by female lac insects after they have eaten a lot of tree bark. The resin is then harvested, heated, filtered. and mixed with an alcohol solution to create a food glaze, so that’s fun. As for dextrose, it’s just a simple sugar that is chemically identical to glucose. wait. so, if sugar, dextrose, honey, and corn syrup are all types of sugar, how much sugar is in these candies?Short answer: a lot. According to the Brach's nutrition label, there are about 28 grams of sugar in 19 pieces, or a serving. In case you were wondering exactly how much that is, one can of regular Red Bull has 27 grams of sugar, according to their website. You read that right; an entire can of Red Bull has less sugar than 19 pieces of Brach's candy corn. And if you were wondering how much sugar your body needs, the American Heart Association recommends women have no more than 25 grams and men have no more than 36 grams of sugar daily. A serving of candy corn is more than my recommended daily sugar intake. So, yeah, candy corn is basically straight sugar. So they aren't made of corn?What do you think corn syrup is? It’s literally a syrup made from corn. Is that why It's called candy corn?No. Candy corn was created to look like individual corn kernels. In fact, it’s original name was “Chicken Feed.” You see, although the candy was originally invented in the 1880s, trick-or-treating wasn’t really big until after World War II, when the sugar rations were lifted. At that point, most of America was agrarian, so, to please the people, they made candy pumpkins, turnips, chestnuts, and clover leaves in addition to the candy corn. While the pumpkins still remain, we have gotten rid of the others, which is probably for the best. so, what is candy corn?A highly controversial fall candy containing Asian Beetle resin and excessive amounts of sugar that became a fall staple by catering to the populous farmers of America, gradually working its way into being a Halloween tradition. curious? Here's some more reading!
According to the New Oxford American Dictionary, "a kind of expanded polystyrene." What the heck is polystyrene?That's an excellent question. Chemistry wise, it's (C8H8)n, a polymer of styrene. Derived form petroleum, styrene itself is toxic; however, it is frequently used in polymer form, which is used in many types of rubber and plastic. Free-radical initiators are usually used to create these polymers. Could you write that in english, please?Absolutely! You should recognize the chemical symbols C and H as the symbols for carbon and hydrogen respectively, assuming you somewhat payed attention in your high school chemistry class. A polymer is simply multiple monomers, or single molecules, stuck together. Free-radical indicators are molecules that have fallen apart such that the electrons are not in pairs, which isn't normal as electrons like to stick together. Since these electrons are desperate for a partner, they will go along with pretty much any other electron that comes along. The double carbon bonds in styrene make it easy for an unpaired electron to bond with a carbon electron. This action creates a new bond that leaves one carbon electron lonely, causing the process to repeat itself over and over again in what is known to chemists as a chain reaction (sound familiar?). This reaction is essentially what creates polystyrene, the basis for most of life as we know it. the basis of life?Yep. As mentioned earlier, polystyrene is used in many types of rubber and plastic. This includes, but is not limited to, plastic cups, air plane models, interior car parts (such as the radio knob), hairdryers, computers, and children's toys. So, yeah, basically everything we do involves polystyrene. But how does a material that makes all this hard, plastic stuff turn into styrofoam?Well, going back to the definition, styrofoam isn't just straight polystyrene; it's expanded rather than solid. How exactly does one expand plastic?I'm getting there! So, the polystyrene chains are made into little balls, as anyone who has let a small child/cat pick at packaging foam would know. (Seriously, those things get everywhere!) After the beads are solidified, they are packed into a mold for whatever product is being made. Steam is then injected into the mold, both expanding the beads and fusing them together. Finally, it is cut into the desired shape, smoothing out rough edges. Wait, if styrofoam is just PLASTIC with steam pumped into it, why is it not recyclable?It is. Next time you drink out of a styrofoam cup, check the bottom. It probably has a recycling sign on it. In fact, in my AP Environmental Science class, we dissolved styrofoam using nail polish remover (which basically just removes the air from in between the balls). Those leftovers could pretty easily be reused to make more styrofoam and whatever else can be made form polystyrene. why is it so bad for the ENVIRONMENT then?It takes forever to decompose (over a million years), and humans aren't that good at recycling it, as evidenced by the fact you probably didn't know it was recyclable until just recently. Additionally, a lot of the things styrofoam is used for (i.e. takeout boxes, hot chocolate cups, picnic plates) make it hard to recycle because of food residue. Furthermore, most styrofoam products aren't reused as much as cardboard or plastic products. This creates more waste in general, as reusing is more efficient than recycling, and therefore better for the earth. Another problem is that most local governments just don't recycle styrofoam for one reason or another. So, What is STYROFOAM?Styrofoam is a polymer of a molecule derived from petroleum (styrene) that has been solidified into annoyingly tiny balls, molded, injected with steam, and then shaped that should be recycled but isn't because of how we use it, resulting in it sitting in land fills for hundreds upon hundreds of years. Curious? Here's some more reading!
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