Molecular Biology and Protein Synthesis

These flashcards cover the key vocabulary regarding DNA structure, genetic reproduction, and the biological steps involved in protein synthesis as described in the lecture notes.

DNA

A molecule made of two strands consisting of chains of building blocks called nucleotides.

Nucleotides

Repeating chemical units that join together to form a DNA molecule, identified by their bases: adenine, guanine, cytosine, and thymine.

Base pairing

The rule where two strands of DNA connect such that adenine (a) pairs with thymine (t) and guanine (g) pairs with cytosine (c).

Asexual reproduction

A form of reproduction involving one parent producing identical offspring, seen in bacteria, amoeba, and body cells.

Sexual reproduction

A form of reproduction involving two parents producing non-identical offspring, seen in humans, animals, and plants.

Gene

A specific segment of DNA that provides instructions for inherited traits, having a specific starting point and ending point.

Protein

An important molecule composed of amino acids required for building and repairing body structures and controlling body processes.

Amino acids

The smaller molecules that combine to make proteins; there are about 20 different types.

Triplet

A specific sequence of three bases on a gene that codes for a specific amino acid.

Enzymes

Proteins that control chemical reactions within the body.

Actin and Myosin

The proteins that make up muscles.

Keratin

The protein that makes up hair and nails.

Hemoglobin

A protein that carries oxygen in the blood.

RNA

A single-stranded molecule containing ribose sugar that can leave the nucleus and travel to the cytoplasm.

Genome

The complete set of genetic instructions, which in humans is split between 23 pairs of chromosomes.

Histones

Proteins around which long strands of DNA are tightly packaged to form chromosomes.

Transcription

The process of converting DNA instructions into messenger RNA (mRNA) occurring in the nucleus.

RNA polymerase

The enzyme that attaches to the start of a gene, reads the DNA, and builds a strand of messenger RNA.

Translation

The process of using messenger RNA to assemble amino acids into a protein, occurring in the cytoplasm at the ribosome.

Ribosomes

Protein factories in the cytoplasm that bind to mRNA and read the code to produce a chain of amino acids.

Transfer RNA (tRNA)

Molecules that carry specific amino acids to the ribosome and deliver them based on the mRNA codon.

Codon

A group of three bases on an mRNA strand that is read by the ribosome to signal a specific amino acid.

Anticodon

A sequence of three bases on a tRNA molecule that pairs with the matching mRNA codon.

Uracil

The base in RNA that replaces thymine and pairs with adenine (A to U).

Introns

Sections of mRNA that are removed by enzymes because they will not be used to build the protein.

Exons

The remaining sections of mRNA that are spliced together to form functional mRNA before leaving the nucleus.

Protein synthesis

The multi-stage process, including transcription and translation, by which the body creates proteins.