DANDY Deoxyribonucleic Acid

ALL CELLS HAVE DNA… Cells are the basic unit of structure and function of all living things. –Prokaryotes (bacteria) –Eukaryotes (animals, plants, etc.)

Deoxyribonucleic Acid DNA is found in the nucleus (of eukarytotes). Remember…the nucleus is the “control center” of the cell.

DNA is found in three forms… Chromatin - Single strands of DNA found in the nucleus when the cell is NOT dividing. Chromatid - Single copy of condensed DNA that is coiled and wound up prior to division. Chromosome - Two copies of DNA (two chromatids) connected prior to cell division.

DNA is the code of life… Genes - segments of DNA that code for specific proteins and therefore specific traits.

D.N.A. Deoxyribonucleic Acid - Hereditary material - Double helix - a “twisted ladder” of nucleotides.

Nucleotides: Sides of the ladder A. Sugar B. Phosphate Steps of the ladder C. Nitrogen Base * Cytosine * Guanine * Adenine * Thymine TA CG GC

The Bases Pair… C always goes with G. –they both have curves. A always goes with T. –they both are made of sticks.

HOW DOES THE DNA “MAGIC” WORK? DNA makes RNA RNA carries protein instructions Which of our friendly organelles makes protein? Where in the cell are they? Where are the chromosomes?

So what is RNA? R.N.A - Ribonucleic Acid Just like DNA except: ** Ribose (sugar) ** Single Stranded ** Uracil instead of Thymine C U A G

How does DNA work? The DNA is Read. 1.The nucleus gets a chemical signal to make a protein. 2. The DNA is opened (unzipped) where the gene starts.

How does DNA work? 3.mRNA pairs up with the DNA template. 4. The DNA closes and the mRNA strand leaves the nucleus.

Let’s Try A DNA Example: 1.Fill in the matching bases for the DNA strand T - C - G - A - G -

Let’s Try A DNA Example: 1.Fill in the matching bases for the DNA strand T - A C - G G - C A - T G - C

RNA Example T - - A C - - G G - - C A - - T G - - C 2. Fill in the new mRNA strand along the left side of the DNA

RNA Example T - A- A C - G- G G - C- C A - U- T G - C- C 2. Fill in the new mRNA strand along the left side of the DNA

Completed RNA 3. Write the new mRNA strand that moves into the cytoplasm

Completed RNA 3.Write the new mRNA strand that moves into the cytoplasm A G C U C

How Powerful Proteins Are Made… 1.The mRNA leaves the nucleus and attaches itself to a ribosome. 2.The ribosome reads the RNA 3 bases at a time (codon). AAGCUCAAGCUC codon mRNA Ribosome

How Powerful Proteins Are Made… 3. For each codon, an amino acid is attached to the ribosome to form a chain of protein. CCG

mRNA CODES FOR AMINO ACIDS Third Base First Base Second Base UCAG UUCAGUCAG Phenylalanine Serine Tyrosine Cysteine Phenylalanine Serine Tyrosine Cysteine Leucine Serine Stop Codon Leucine Serine Stop Codon Tryptophan CUCAGUCAG Leucine Proline Histidine Arginine Leucine Proline Histidine Arginine Leucine Proline Glutamine Arginine Leucine Proline Glutamine Arginine AUCAGUCAG Isoleucine Threonine Asparagine Serine Isoleucine Threonine Asparagine Serine Isoleucine Threonine Lysine Arginine Methionine Threonine Lysine Arginine GUCAGUCAG Valine Alanine Aspartic Acid Glycine Valine Alanine Aspartic Acid Glycine Valine Alanine Glutamic Acid Glycine Valine Alanine Glutamic Acid Glycine

How Powerful Proteins Are Made… 4. After reading the RNA the ribosome sends the protein chain to the golgi complex to be packed and shipped. Shipped to Golgi

Let’s continue our example… A - G - C - U - C - mRNA -Amino Acids Rockin’ Ribosome

Let’s continue our example… A - G - C - U - C - mRNA - Amino Acids Rockin’ Ribosome Lysine Leucine

Let’s try the whole thing!!! T - A - C - G - A - C - T - D.N.AR.N.AAmino Acids Rockin’ Ribosome

Let’s try the whole thing!!! T - A A - T C - G G - C A - T C - G T - A D.N.AR.N.AAmino Acids Rockin’ Ribosome

Let’s try the whole thing!!! T - A A - T C - G G - C A - T C - G T - A D.N.AR.N.AAmino Acids Rockin’ Ribosome AUGCCUGGAAUGCCUGGA Methionine (start codon) Proline Glycine