32. Molecular base of heredity. DNA and RNA - structure and functions. Flashcards
1
Q
Structure of DNA:
- made up of 2 antiparallel strands of joined nucleotides connected together
- nucleotides consist of a deoxyribose sugar (monosaccharides), N base (nitrogenous base) of the purine, pyrimidine origin and a phosphate group
- N base is connected to carbon 1 of deoxyribose sugar by a glycosidic bond
- two nucleotides are bonded together by a phosphodiester bond between carbon 3 of one deoxyribose sugar and carbon 5 of the other deoxyribose sugar
- pyrimidines in DNA are cytosine + thymine
- purines in DNA are adenine + guanine
- bases bind by complementary base pairing - A + T and C + G
A
Structure of DNA:
- made up of 2 antiparallel strands of joined nucleotides connected together
- nucleotides consist of a deoxyribose sugar (monosaccharides), N base (nitrogenous base) of the purine, pyrimidine origin and a phosphate group
- N base is connected to carbon 1 of deoxyribose sugar by a glycosidic bond
- two nucleotides are bonded together by a phosphodiester bond between carbon 3 of one deoxyribose sugar and carbon 5 of the other deoxyribose sugar
- pyrimidines in DNA are cytosine + thymine
- purines in DNA are adenine + guanine
- bases bind by complementary base pairing - A + T and C + G
2
Q
Structure of RNA:
- same as DNA except, instead of thymine it’s uracil
- single stranded - sugar is ribose instead of deoxyribose
A
Structure of RNA:
- same as DNA except, instead of thymine it’s uracil
- single stranded - sugar is ribose instead of deoxyribose
3
Q
Functions of DNA:
- control and regulation of cellular activity (transfers genetic messages to all of the cells in your body)
- DNA replication for reproduction and maintenance and growth of cells, tissues and body systems
- codes for proteins which have various important functions
- protein synthesis
A
Functions of DNA:
- control and regulation of cellular activity (transfers genetic messages to all of the cells in your body)
- DNA replication for reproduction and maintenance and growth of cells, tissues and body systems
- codes for proteins which have various important functions
- protein synthesis
4
Q
Functions of RNA:
- some RNA molecules act as catalysts - ribozymes - they are usually precursors of rRNA, reduce the internal segments of themselves, splicing the ends together
- RNA acts also as ribonuclease, cleaving other RNA molecules
- peptidyl transferase - composed of RNA
- mRNA (messenger RNA) - acts as a template for protein synthesis
- rRNA (ribosomal RNA)- associates with proteins to form ribosomes
- tRNA (transfer RNA) - adapters between mRNA + amino acids (contains own specific amino acid - binds to polypeptide chain if mRNA calls for it), reading of mRNA
A
Functions of RNA:
- some RNA molecules act as catalysts - ribozymes - they are usually precursors of rRNA, reduce the internal segments of themselves, splicing the ends together
- RNA acts also as ribonuclease, cleaving other RNA molecules
- peptidyl transferase - composed of RNA
- mRNA (messenger RNA) - acts as a template for protein synthesis
- rRNA (ribosomal RNA)- associates with proteins to form ribosomes
- tRNA (transfer RNA) - adapters between mRNA + amino acids (contains own specific amino acid - binds to polypeptide chain if mRNA calls for it), reading of mRNA