Nucleic Acid Carbohydrate and Nitrogenous Bases

Structure of RNA + DNA

• a nitrogen-containing base + pentose sugar = nucleoside

• nucleoside + phosphate =  nucleotide

Nucleic Acids

are polymers of nucleotides with very specific functions in cells

DNA

nucleotide sequence stores genetic code for replication and sequence of amino acids

RNA

single stranded nucleic acid that translates genetic code of DNA into the amino acid sequence of proteins

Nucleotides 

have independent metabolic functions in cells

Co-enzymes

facilitate enzymatic reactions

• ATP is a nucleotide used to supply energy

DNA

is a polymer of nucleotides, each consisting of 3 components

• a nitrogenous base

• a sugar

• a phosphate group

Nucleotide polymers

are made up of nucleotides linked by 3 carbon of one nucleotide and the phosphate on the 5 carbon on the next nucleotide

Carbohydrates

ribose and deoxyribose are five carbon sugars/pentose

• they make up the backbones of RNA and DNA

Nitrogen bases

rings of carbon and nitrogen

two types of nitrogen bases

1. pyrimidines; have a single six-membered ring

2. purines; have a six-membered ring joined to a five-membered ring

Plasma membrane

Carbohydrates chains of glycolipids and glycoproteins and forms a sugar coat called glycoproteins

Glycocalyx

• protects the cell

• plays a role in adhesion between cells

• reception of signal molecules

• cell to cell recognition

Plasma membrane

carbohydrate chains of glycolipids and glycoproteins

• have a role in organ rejection

  • if organs are rejected when transplanted from one person to another person

  • the foreign cells have different carbohydrate chains to the host

Carbohydrate chains

basis for the;

• A

• B

• O

  • blood groups in humans