What are nucleotides composed of?

Nucleotides consist of nitrogenous bases, ribose sugar, and phosphoric acid residue.

How is DNA structure visualized?

DNA structure resembles a double helix with nitrogenous bases forming rungs and a phospho sugar backbone as sides.

The central dogma states that DNA is transcribed into RNA, then translated into proteins.

RNA has ribose sugar, uracil base, is single-stranded, and smaller than DNA.

Protein synthesis begins with the start codon AUG and involves transcription and translation.

Genes on chromosomes determine physical traits through inheritance, with DNA and RNA playing crucial roles as nucleic acids in molecular biology.
The structure of DNA, with purines (adenine, guanine) and pyrimidines (cytosine, thymine, uracil) forming distinct nitrogenous bases, showcases a double-stranded helix held together by hydrogen bonding following specific base pairing rules, crucial for protein expression and genetic coding.

What are nucleotides composed of?
Nucleotides consist of nitrogenous bases, ribose sugar, and phosphoric acid residue.
How is DNA structure visualized?
DNA structure resembles a double helix with nitrogenous bases forming rungs and a phospho sugar backbone as sides.
What is the central dogma of molecular biology?
The central dogma states that DNA is transcribed into RNA, then translated into proteins.
What are the differences between DNA and RNA?
RNA has ribose sugar, uracil base, is single-stranded, and smaller than DNA.
How is protein synthesis initiated?
Protein synthesis begins with the start codon AUG and involves transcription and translation.

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Physical traits are inherited as genes located on chromosomes, forming the human genome.
Diploid and haploid cells, with haploids being gametes, are discussed.
Molecular biology focuses on DNA and RNA as nucleic acids.
Nucleotides, the monomeric units of nucleic acids, consist of nitrogenous bases, ribose sugar, and phosphoric acid residue.
The order of nitrogenous bases specifies the genetic code, crucial for protein expression.
Purines (adenine, guanine) and pyrimidines (cytosine, thymine, uracil) are the nitrogenous bases.
The structures of purines and pyrimidines are distinct, with thymine and uracil being similar.
Nucleotides for DNA and RNA differ based on the presence or absence of oxygen at the 2' carbon of the ribose ring.
Nucleotides form a backbone through 3' to 5' phosphodiester linkages.
DNA is a double-stranded helix with anti-parallel strands held together by hydrogen bonding following Watson and Crick's base pairing rules.

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DNA base pairing: A-T held by 2 hydrogen bonds, G-C by 3 hydrogen bonds, indicating tighter binding with GC pairs.
Structure of DNA: Phosphodiester linkages connect 3' OH to 5' carbons, forming the backbone of the double helix.
Linkages in biological macromolecules: Carbohydrates linked by alpha 1-4 or beta 1-4, lipids by esters, proteins by amides, nucleic acids by phosphodiester.
DNA structure visualization: Double helix resembles a rope ladder with nitrogenous bases forming rungs and phospho sugar backbone as sides.
Grooves in DNA structure: Wide and thin grooves formed by winding the rope ladder around the central axis, potentially used for research in activating specific areas.
Eukaryotic DNA: Contains 3 billion base pairs, with the human genome project completed in the early to mid '90s.
DNA packaging: DNA wraps around histone proteins with basic residues, forming chromatin and eventually chromosomes efficiently.
Differences between DNA and RNA: RNA has ribose instead of deoxyribose, contains uracil instead of thymine, is single-stranded, and smaller than DNA.
Protein synthesis: DNA transcribed into RNA, then translated into proteins, following the central dogma of molecular biology.
Types of RNA: Messenger RNA (mRNA) carries genetic information, transfer RNA (tRNA) transports amino acids, ribosomal RNA (rRNA) is abundant in ribosomes for translation.

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Codons are crucial in determining the amino acids in protein synthesis, with tRNA binding to the complementary anti-codon sequence.
Leucine, an important amino acid with 6 codons, can tolerate point mutations in DNA while still encoding for the same amino acid.
Protein sequencing from DNA is less accurate due to similar proteins resulting from identical amino acid sequences despite variations in codons.
The start codon AUG initiates protein translation, while premature stop codons can lead to non-functional proteins.
During protein translation, the ribosomal subunits recognize the start sequence, with the P site holding the growing peptide chain and the A site binding incoming amino acids until reaching a stop codon.