1. Annie Perales and Miranda Viorst
DNA and Genetics
Annie Perales and Miranda Viorst

2. DNA Basics
DNA is hereditary information in the form of a large molecule titled deoxyribonucleic acid.
DNA can either be enclosed within a structure made of membrane or made as a loop.
A short segment of DNA that contains instructions for the development of a single trait of an organism is called a gene.

3. Gene Expression in Prokaryotes
The activation of a gene is called gene expression.
Gene expression results in the formation of a protein.

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A genome is the complete genetic material contained in an organism.
By regulating gene expression, cells are able to control which part of the genome will be expressed and when it will be expressed.

5. Parts of the DNA in Prokaryotes
Operons are made up of three parts.
The first is the promoter. A promoter is a DNA segment that promotes transcription.

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The second is an operator. It binds together inhibitory proteins and prevents protein synthesis from occuring.
Structural genes are the third part. They are genes that code particular chains of amino acids.

7. Gene Expression in Eukaryotes
The coiling and uncoiling of DNA within each chromosome is partially related to gene expression in eukaryotes.
Before mitosis or meiosis, DNA coils tightly, making the structures be called chromosomes. This process makes transcription possible.
The degree to which the DNA is uncoiled shows the degree of gene expression

8. Parts of the DNA in Eukaryotes
Like the prokarayote, there is also a promoter, although there are two different segments beyond the promoter.
The first one is introns. They are sections of a-

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structural gene that do not code for amino acids. This means that they are not translated into proteins.
The second one is exons. These are sections of a structural gene that are translated into proteins when expressed

10. Structure of DNA A DNA nucleotide has three parts.
The first is a sugar molecule which is called deoxyribose. This is where the “D” and the “N” in DNA come from.
The second is a phosphate group which is made up of phosphorus and oxygen.
The third is a molecule that contains nitrogen.

11. Structure of DNA cont.
IN DNA there can be any one of four different kinds of nitrogen containing bases.
These are adenine, guanine, cytosine, and thymine.
This explains why the letters used to explain DNA are always A, G, C, and T.

12. Transcription
Transcription is the process where genetic information is transferred from DNA to RNA.
RNA is nucleic acid made up of repeating nucleotides.

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RNA is not the same as DNA because of its structure. It contains the same nitrogen containing bases as DNA and also contains uracil.
Also, RNA stands for ribonucleic acid.

14. Cell Differentiation
Although all cells in an organism contain the same genes, only a part of the genes are expressed.
Certain genes turn on and off at different times during the organism’s life.

15. Cell Differentiation Cont.
Cell differentiation is the development of cells having specialized functions.
Examples of cell differentiation are cancer, colorblindness, muscular dystrophy, and downs syndrome.

16. Translation
Translation is the process of assembling long chains of amino acids from information encoded in mRNA.
mRNA is the type of RNA that carries genetic information from the nucleus to other parts of the organism.
Translation begins when mRNA leaves the nucleus and migrates to an organelle called the ribosome.

17. Inheritance
The chromosome is DNA in a coiled, rod-shaped form that is formed from cell division.
Chromosomes determine just about every trait in an organism.
One main trait in an organism is the individual’s sex.
This can either be XY, which stands for male, or XX, which stands for female.
This process can often be confusing, but can be better understood with a punnett square.

18. This is a Punnett Square!