2.  RNA: Ribonucleic Acid  3 types  Helps cells make protein  Single strand of nucleotides: › Ribose sugar › Phosphate › Nitrogen bases  Adenine, uracil, guanine, cytosine

3. Base pair rules  Uracil always pairs with Thymine  Cytosine always pairs with Guanine

4.  m = messenger  Found in the nucleus and cytoplasm  Makes a copy of DNA to take to ribosome for protein synthesis  Codons › Every 3 letter base sequence on mRNA › 1 codon = 1 amino acid

5.  t = transfer  Found in the cytoplasm  Carries amino acids to the ribosome  Anti-codon › Complementary 3 base sequence to mRNA’s codon amino acid anti-codon

6.  r = ribosomal  Found in cytoplasm  Makes up ribosomes

8. DNA  RNA  Protein

9.  Organisms are a collection of traits!

10.  Entire set of DNA for an individual organism is located on 46 chromosomes. Segments of these chromosomes are called ________.  Every cell of an organism has the same exact set of DNA

11.  Molecular process of converting DNA genes into a trait is called gene expression.

13.  Stage 1: Transcription › Gene (section of DNA) is converted into mRNA code › In nucleus  Stage 2: Translation › mRNA, tRNA, rRNA link amino acids based on code › In cytoplasm

14. How does the cell determine what amino acid goes with the mRNA’s codon? CODON = AUG Start in the center and work your way out A U G Amino acid is methionine Try finding the amino acid for the codon ‘CUA’ LEUCINE Codon Table

15.  In multicellular organism not all genes are expressed in all cells.  Different parts of the genetic instructions (DNA) are used in each type of cell. › For example a liver cell has different genes “turned on” being expressed than a heart cell. › This is called differentiation and happens while the baby is growing inside the womb.

16.  Frogs undergo metamorphosis from tad pole to frog. The time this process takes depends on environmental conditions even though the genes are the same. › If it has been a dry season or there is a shortage of food, for example, then the tadpole stage may be cut short and development may be quicker