Central Dogma of BiologyFind 15 Notes!

Mr. Rosenberg

The Central Dogma is . . .

• 1. DNA→RNA→Protein

DNA vs RNA

• 2. Components of DNA– Sugar (deoxyribose)– Base (A,G,C,T)– Phosphate group

• 3. Components of RNA– Sugar (ribose)– Base (A,G,C,Uracil)

• RNA does not contain thymine

– Phosphate group

Just a Bit Different - Sugar

Just a Bit Different Part 2 - Bases

• DNA has:– A– T– C– G

• RNA has:– A– U– C– G

DNA vs RNA continued

• 4. Structural Characteristics of DNA– Double stranded– Base-pairing rules apply (A:T & G:C)

• 5. Structural Characteristics of RNA– Primarily single stranded– Base-pairing rules apply (A:U & G:C)

6. 3 Main Types of RNA

• Messenger RNA (mRNA)

• Ribosomal RNA (rRNA)

• Transfer RNA (tRNA)

mRNA

• 7. Messenger RNA (mRNA)– Complementary to info in DNA strand– Variable in length– Contains specific structural info for the

sequence of amino acids– Processed before using

tRNA

• 8. Transfer RNA (tRNA)– Multiple varieties, each specific for a specific

amino acid– Relatively small, with a consistent 3-d shape– There is a triplet base-pairing relationship

between codon on mRNA and anti-codon on tRNA

rRNA

• 9. Ribosomal RNA (rRNA)– Ribosomes are composed of rRNA – simple!

The Central Dogma

10. DNA RNA Protein

Transcription and translation are the two processes of the Central Dogma

• 12. DNA transcribes RNA is translated to Protein

DNA→RNA→Protein

• 13. DNA TRANSCRIBES mRNA

• mRNA is carried out of the nucleus

• 14. tRNA is TRANSLATED into protein

• In a eukaryotic cell, almost all transcription occurs in the nucleus and translation occurs at ribosomes in the cytoplasm.

Fig. 17.2b

15. The molecular chain of command in a cell is

DNA → RNA → protein.

This is referred to as the Central Dogma of Biology