Why are chromosomes important to heredity? Why is DNA called the blueprint of life? How do genes differ from chromosomes? How can chromosomes be damaged? How the bases are arranged in the DNA is what determines the genetic code. Each contains one side of the original DNA and one side made of "new" nucleotides.
It is possible that mistakes were made along the way -- in other words, that a base pair in one DNA molecule doesn't match the corresponding pair in the other molecule. On average, one mistake may exist in every billion base pairs. We know the nucleus controls the cell's activities through the chemical DNA, but how?
It is the sequence of bases that determine what protein is to be made. The only problem is that the DNA is too big to go through the nuclear pores.
So a chemical is used read the DNA in the nucleus. That chemical is messenger RNA. It takes the "message" of the DNA to the ribosomes and "tells them" what proteins are to be made.
Recall that proteins are the body's building blocks and are made of individual amino acids joined into a long chain. Imagine that the code taken to the ribosomes is telling the ribosome what is needed - like a recipe. Instead of thymine, mRNA contains the base uracil. In addition to that difference, mRNA has the sugar ribose instead of deoxyribose. RNA stands for ribonucleic acid. Color the ribose a darker blue. Color the uracil brown.
Each time a new cell is made, the cell must receive an exact copy of the parent cell DNA. The new cells then receive the instructions and information needed to function.
The process of copying DNA is called replication. This means that even though the genetic code for all human beings is Knowing this, DNA can be used to identify people in a variety of situations.
This field is known as forensic science. DNA is often used to solve crimes by identifying victims and suspects while at the same time ruling out innocent people as possible suspects for a crime.
It is also used to prove or disprove family relationships, identify missing persons, and identify the victims of catastrophes who are no longer physically identifiable. And since DNA can be found in a variety of human tissues and fluids such as hair, urine, blood, semen, skin cells, bones, teeth, and saliva, it greatly aids in identification when other methods, such as fingerprints and teeth structure, are no longer usable. The medical field also uses DNA. Now that doctors at least partially understand how DNA works, modern medicine has made advances in identifying diseases and finding cures.
Many diseases, like cystic fibrosis, are hereditary diseases, meaning they are passed on from parent to offspring. By looking at the DNA of an individual, doctors can determine what the disease is or how susceptible a person or their children are to having a particular disease.
Doctors also study how cells with damaged DNA multiply to help them find cures or treatments for diseases such as cancer and tumors. But knowledge of DNA is not just used in humans. Food scientists use DNA information to improve crops and develop new food sources. Plant breeders select plants that produce high yields of food, are resistant to pests, and tolerate environmental stresses better than similar plant varieties.
However, there has been growing debate on whether or not these genetically modified food sources are safe and healthy for human consumption. To help further understand how DNA is structured, build a model of it. This is a simplified model of DNA, but it will still give you the general idea of how the sugars, phosphate groups, and bases all connect together to make the famous double helix shape of DNA.
You can make a model out of a variety of materials. Make two equal lengths of licorice strands by threading the pieces of licorice onto the string, alternating the red and black pieces.
Pair two colors of the gummy bears together and then pair two other colors together.
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