Nucleic Acids

Nucleic Acids Nucleic acids (polymer) are long chains of nucleotides (monomer). A nucleotide is composed of phosphate, sugar, and a nitrogen base.

Nucleic Acids There are 2 types of nucleic acids: DNA RNA Functions nucleic acids: Store/transmit genetic information Instructions for making proteins

DNA

DNA DNA stands for Deoxyribonucleic Acid. DNA is shaped as a double helix because it looks like a twisted ladder **Designed by Watson and Crick DNA contains our genetic information and is stored in chromosomes the nucleus of our cells.

DNA The sugar for DNA is called deoxyribose sugar. Sugar

DNA Nitrogen Bases There are 2 groups of nitrogen bases: Purines Double-ringed structures Pyrimidines Single-ringed structures Nitrogen base

DNA Nitrogen Bases There are 4 types of nitrogen bases found in DNA Adenine(A) Guanine(G) Cytosine(C) Thymine(T)

DNA Nitrogen Bases **Therefore… Adenine(A) and Guanine(G) = Purines (double ringed) Cytosine(C) and Thymine(T) = Pyrimidines (single ringed)

Chargaff’s Rule nucleotide Erwin Chargaff Complementary Base Pairing # A = # T and # C = # G Therefore… A pairs with T and C pairs with G

Video Video (4:21)

Practice on your own! Complete the following complementary base pairing: A T G C A G G C A T

Practice on your own! Complete the following complementary base pairing: A T G C A G G C A T T A C G T C C G T A

Let’s try again! - Practice on your own! Complete the following complementary base pairing: G C T T A A G T C A G C

Let’s try again! - Practice on your own! Complete the following complementary base pairing: G C T T A A G T C A G C C G A A T T C A G T C G

Bonding Hydrogen bonds hold the nitrogen bases together. The hydrogen bonds are weak bonds. Hydrogen bond

DNA The nucleotide sequence is very important Unique for each species Unique for each individual The more alike two species, the more alike their DNA

RNA Structure

RNA RNA stands for Ribonucleic Acid. RNA is single stranded. RNA decodes the genetic information stored in DNA and can travel in our cells

RNA The sugar for RNA is called ribose sugar. Sugar

RNA There are 4 different nitrogen bases for RNA Cytosine (C) Guanine (G) Adenine (A) Uracil (U) A and U pair together C and G pair together Nitrogen base

DNA & RNA DNA = Deoxyribonucleic Acid RNA = Ribonucleic Acid Double stranded Single stranded Deoxyribose sugar Ribose sugar Nitrogen bases = A & T; G & C Nitrogen bases = A & U; G & C **(U=Uracil)** Replicates DNA → DNA Does not replicate Only one type 3 types: mRNA, rRNA, tRNA

Types of RNA Messenger RNA (mRNA) - carries the DNA message from nucleus through cytoplasm to ribosome. *Notice single stranded *Notice nitrogen base is Uracil, not Thymine G U A G C U A

Types of RNA 2. Ribosomal RNA (rRNA) - makes up ribosomes RNA glob up along with proteins to make ribosomes Ribosomes are where proteins are made

Types of RNA 3. Transfer RNA (tRNA) - Links amino acids together A single RNA chain folded into T-shape Location - cytoplasm and ribosomes

Types of RNA

DNA vs RNA video video (4:43)