1. DNA, Genes, & Proteins

2. Pop Quiz! The DNA molecule supplies _________________ for cells. Is DNA able to be copied? What is DNA made of? What are the four bases? Which bases bond together? What three things make up a nucleotide?

3. Copying DNA The DNA molecule gets split down the middle. Bases on both sides are exposed. Complementary nucleotides are added to each side, creating TWO DNA molecules. All of this happens every time a cell divides. Proteins are the ones that do the job. You’ll usually see DNA with several kinds of proteins.

4. Genes & Chromosomes DNA holds information in its genes. A gene is a string of nucleotides that gives the cell information about how to make a specific trait. Chromosomes are strands of DNA that have been wound around proteins and then bunched up. Chromosomes contain the genes and are found in the cell’s nucleus. Human cells contain 23 different pairs of chromosomes.

5. Genes & Proteins Remember when I said that a gene gives the cell information about how to make a specific trait? How does this work? Each gene has instructions for making one protein. Proteins determine your traits. They are called the building blocks of life!

6. What are some examples of traits?

7. So… how does a gene make a protein? Remember – Genes are made of DNA, and DNA is made of bases. A set of three bases forms an amino acid. Amino acids form proteins.

8. Term to Know: RNA RNA stands for ribonucleic acid. RNA is a copy of half of the DNA. It is used to help make the amino acids.

9. The Protein Factory: Ribosome One side of the DNA copies (mRNA) mRNA (messenger RNA) comes out of the nucleus mRNA fed through the ribosome 3 bases at a time tRNA (transfer RNA) comes to translate the message Bases of mRNA and tRNA line up tRNA releases the amino acid Amino acids join together to make a protein

10. Pop Quiz 2! Proteins determine your _______________. How many bases does it take to make an amino acid? What does a string of amino acids make? What is the “protein factory” called? What is RNA and what does it help do? How often do DNA molecules copy? What copies DNA? What is a gene? What is a chromosome? Where are chromosomes found? Each gene codes for one _______________.

11. Protein Research There are 50,000 different types of proteins that perform different functions! Some examples are found here: http://ghr.nlm.nih.gov/handbook/howgeneswork/pro tein. http://ghr.nlm.nih.gov/handbook/howgeneswork/pro tein http://ghr.nlm.nih.gov/handbook/howgeneswork/pro tein Choose a protein to research. Tell us what type it is and what it does for the body.