Lets compare it to the normal stuff in our lives. What if we could turn a water faucet on, but not off? What would happen if all traffic signals were always green? What if there were no brakes in your car, just an accelerator? These are just a few examples of how we can best accomplish something by using both a positive force and a negative force. Scientists would say we get done exactly what we want to do by using "regulation". Nature has many ways to regulate things. In the case of protein synthesis, breaking down the mRNA is a major means of regulating exactly how much and what kinds of proteins are made. When the cell wants to make a certain protein, it turns on the gene for the protein and mRNA is made. That mRNA moves into the cytoplasm where it teams up with ribosomes and tRNA and amino acids to create the protein. What happens when the cell has enough of that protein? How can it stop the protein from being made if the mRNA hangs around forever? By constantly breaking down the mRNA, the cell can stop the protein from being made by just not making any more mRNA for that protein.
If the mRNA were not broken down, proteins would keep getting made until the cell were full of proteins. The cell would not be able to make only the number of each that it needs. Like the faucet example, the cell would be "flooded" with too many proteins.
Thanks for your great question,
Hello our names are Jeff and Marilyn. We are 12 years old and we are doing a project on protein in our health class. We need information about protein. Here's some of the things we need to include in our project:
Please try and answer some of my questions.
This is what I know about your questions.
Proteins are made up of small pieces called amino acids. These amino acids are strung together in a chain; like the beads of a necklace. Your body can make most of the 20 amino acids that can be in a protein. These types of amino acids are called 'non-essential' and can be made from sugar and other amino acids and stuff like that. But, your body can not make 8 of the amino acids. These 8 are called 'essential' amino acids, and you must eat the proteins that contain those amino acids. You must also take in protein just so you can convert the food amino acids into the exact assortment of amino acids that your body needs.
There are two major functions of protein. One is for structural support, like wood is in a house. Such structures can be found in such things as skin or inside the cells as a scaffolding to keep the cell's shape. The second is for chemical activity. The proteins of the second type do all sorts of 'reactions'. They are called enzymes. They help you digest your food, fight infections, and make the stuff you need to grow bigger.
Food containing protein are such things as meat, eggs, milk, fruits and vegetables. If you eat good meals, you will get this nutrient in your diet. The U.S. Department of Agriculture suggests that a person get at least 1/1000 of their body weight each day in the form of protein.
I do not know if you can get too much protein. But, you can get too little. If you do not get enough protein, you can not grow and your body will begin to break down your own muscles trying to get protein; so you would get weak and sick.
When babies drink their mother's milk, they get proteins called antibodies. These mother's antibodies help infants fight off diseases. After a couple of months, babies can make their own antibodies and do not need them from their moms.
I hope this information helps.
means "I found it!" and is the cry of discovery, both scientific and
otherwise. The best of luck to you.
Brown eye trait is the
dominant trait. The basic reason is that if the eye makes both brown and
blue pigment, the result will still look brown. Sometimes the dominance of
an allele is as simple as that.
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