Chem Chapter 22 Final Notes - Nucleosides/tides and RNA types

What is a nucleoside?

A combination of a nitrogenous base (purine or pyrimidine)

A sugar (ribose for RNA or deoxyribose for DNA)

without a phosphate group.

What is a nucleotide?

A nucleoside (base + sugar) with one or more phosphate groups attached.

What are the components of a nucleotide?

A nitrogenous base (purine or pyrimidine)

A pentose sugar (ribose for RNA, deoxyribose for DNA)

One or more phosphate groups

What are the names of the nucleosides for the purines adenine and guanine?

Adenine + Ribose = Adenosine

Guanine + Ribose = Guanosine

What are the names of the nucleosides for the pyrimidines cytosine, thymine, and uracil?

Cytosine + Ribose = Cytidine

Thymine + Deoxyribose = Thymidine

Uracil + Ribose = Uridine

What is the difference between a nucleoside and a nucleotide?What is the difference between a nucleoside and a nucleotide?

A base + sugar, while a nucleotide is a nucleoside + one or more phosphate groups

What are the types of RNA?

mRNA (Messenger RNA)

tRNA (Transfer RNA)

rRNA (Ribosomal RNA)

hnRNA (Heteronuclear RNA, precursor to mRNA)

snRNA (Small Nuclear RNA)

What is the role of mRNA?

mRNA carries the genetic code from DNA to the ribosomes for protein synthesis.

What is the role of tRNA?

tRNA carries amino acids to the ribosome and matches its anticodon to the mRNA codons, facilitating protein synthesis.

What is the role of rRNA?

RNA is a key component of ribosomes and is involved in the synthesis of proteins

What is hnRNA?

hnRNA (heteronuclear RNA) is the initial transcript from DNA, which includes both coding (exons) and non-coding (introns) regions before splicing

What is snRNA?

snRNA (small nuclear RNA) is involved in the splicing of hnRNA to remove introns and join exons

Sugar in RNA

Ribose

Sugar in DNA

Deoxyribose

Thymine is in

DNA

Uracil is in

RNA

Which sugar has an -OH group?

Ribose; RNA

What sugar has an -H group, lacks an -OH group?

Deoxyribose; DNA

What are the purines?

Adenine and guanine

What are the pyrimidines?

Cytosine, thymine, and uracil