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2.2 Final Make Up Day: Intro to Genetics Reading

When you look in the mirror and see yourself, do you ever wonder, “Why do I look this way?” The answer comes down to DNA. DNA is your genetic material that controls everything about you, from the way you look to your personality! That’s right, these molecules called DNA control your physical features like; height, hair color, eye color, nose shape, and skin color. The DNA also controls elements of your personality like; shyness, outgoingness, and aggressiveness. DNA is what makes you, you!

So what exactly is DNA? DNA stands for deoxyribonucleic acid. DNA is stored in the nucleus of the cell. DNA contains the information that controls your cells. Your DNA has directions that tell your cell how to work, and the DNA is stored in the nucleus.This is why the nucleus is called the command center of your body.

But how does the information in your DNAcontrol your cell if it’s stuck in the nucleus? The DNA in your nucleus gets the information to control the cell by copying itself into RNA. The RNA is then able to leave the nucleus through the pores in the nuclear membrane. Pores means holes, and the nuclear membrane is the membrane that surround the nucleus. So, nuclear pores means the holes in the membrane around the nucleus.
So what exactly is RNA? RNA stands for ribonucleic acid. RNA is a closely related to DNAbecause it is direct copy of the information on the DNA, with some very subtle differences. Subtle means unnoticeable and small. The differences are like writing the information in pen and then copying it in pencil. The information is the same, but slightly different.
This still doesn’t quite explain how DNA controls the cell. Right now we have RNA, with the information from the DNA, which has just left the nucleus. The RNA is now swimming through the cell looking for a ribosome. Once the RNA finds the ribosome, the ribosome takes the information and makes a protein. The DNA is the instructions for the ribosomes. The RNA is a copy that travels to the ribosome. The ribosome uses the instructions to make a protein.

So far in class, we have talked about a bunch of different proteins. There are proteins in the membrane that let good stuff into the cell, proteins make RNA from DNA, and proteins are made by the ER and shipped by the golgi apparatus. In our cell we have thousands of different proteins. Each different protein is made from a different gene. Genes are small sections of DNA that make a special protein. Each gene in your cell makes 1 protein. Each cell has about 30,000 genes. Each gene plays a role in making you, you. There are 30,000 little pieces of instructions that tell your cells how work. This means there are 30,000 sections of DNA in each cell, there are 30,000 RNA molecules that can get copied, and there are 30,000 proteins that can be made. DNA is called genetic material, because it is made of so many genes. The word genetic comes from the word genes, and genes come for your parents.

When you look at a cell with a microscope, you can’t see the DNA double helix. The double helix is the spiral shape DNA has that looks like a winding staircase. The reason why you can’t see the double helix is because it is too small for even a microscope to see. When you look into the nucleus of the cell, you can see DNA, but you see it as a chromosome. The chromosome is the condensed version of DNA and looks like a giant X. Condensed means packed in very tight. DNA is stored as chromosomes in the cell. It only unpacks itself to make a RNA copy of a gene.

In a humans, there are 23 different chromosomes, and they are numbered chromosome 1, chromosome 2, chromosome 3… all the way to chromosome 23. In our cells, we have two copies of each chromosome. If we have 23 different chromosomes and two copies of each 1, then we have 46 chromosomes total in each cell. 23 chromosomes came from your mom and the other 23 chromosomes came from your dad.
In your body, each chromosome has the exact same information because you have the same DNA in all your cells. Although I have 46 chromosomes, and my best friend also has 46 chromosomes, my chromosomes have different information and directions written in them than my friend, so my cells work slightly different and I look very different. My 46 chromosomes are unique, or special, to me because my 30,000 genes are unique, or special, to me and my DNA is unique, or special to me. / 1. What types of things do DNA molecules control?
DNA molecules control things like…
2. What are some examples of physical features that DNA controls?
Some examples of physical features that DNA controls are…
3. What are some examples of personality traits that DNA controls?
Some examples of personality traits that DNA controls are…
4. What does DNA stand for?
DNA stands for…
5. Where is DNA stored?
6. Why is the nucleus called the command center of your body?
7. What is DNA converted to so it can get the information out of the nucleus?
8. What does the RNA leave the nucleus through?
9. What does the “pores in the nuclear membrane mean” in simpler terms?
10. What does RNA stand for?
11. Why is RNA closely related to DNA?
12. After leaving the nucleus, what is the RNA swimming around the cell looking for?
13. What does the ribosome do with the information from the RNA?
14. What type of proteins have we talked about in class?
15. What is each different protein made by?
16. How many genes are in you body?
17. How many proteins are in your body?
18. Why is DNA called genetic material?
19. What is a DNA double helix?
20. Why can’t you see the double helix with a microscope?
21. What are chromosomes?
22. What does condensed mean?
23. What does DNA unwind itself?
24. How many different chromosomes do you have?
25. How many copies of each chromosome do you have?
26. How many chromosome do you have total?
27. How many chromosomes came from your mom? How many from your dad?
28. Why are my 46 chromosomes different from my best friends?
29. Why are my 46 chromosomes unique?

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