DNA, Transcription, and Translation Practice Flashcards

Vocabulary flashcards covering DNA structure, replication, transcription, and translation, including molecular details and cellular differences.

DNA

A double helix structure resembling a twisted ladder where the sides are sugar and phosphate and the rungs are base pairs.

Base Pairing Rules (DNA)

Adenine (A) always pairs with Thymine (T), and Guanine (G) always pairs with Cytosine (C).

Gene

A specific section or segment of DNA that codes for a specific trait or protein.

Replication

The process essential for cell division that ensures each new cell receives an identical copy of the genetic material by creating two identical DNA molecules.

The Central Dogma

The general flow of genetic information from DNA to RNA to protein.

DNA (Deoxyribonucleic Acid)

A molecule that stores the genetic code within the nucleus.

RNA (Ribonucleic Acid)

A molecule related to DNA that plays a crucial role in carrying out genetic instructions.

mRNA (Messenger RNA)

A molecule that carries the genetic message from the DNA in the nucleus to the ribosomes in the cytoplasm.

tRNA (Transfer RNA)

Molecules that act like delivery trucks, bringing specific amino acids to the ribosome based on mRNA instructions.

Transcription

The first step in building proteins where a section of DNA is used as a template to create a complementary strand of mRNA.

Base Pairing Rules (RNA Synthesis)

Adenine (A) pairs with Uracil (U), and Guanine (G) pairs with Cytosine (C).

Translation

The process where the mRNA sequence is read by ribosomes at the site of protein synthesis to assemble a chain of amino acids.

Codon

A group of three consecutive bases on the mRNA or DNA molecule that specifies a particular amino acid.

Amino Acids

The building blocks of proteins, of which there are 20 common types.

Number of Possible Codons

With 4 possible bases and 3 bases per codon, there are $4^3 = 64$ possible combinations.

Chromosome

DNA packaged with proteins into a compact structure.

Protein

Molecules made of a specific sequence of amino acids that perform most functions in living organisms.

Ribosomes

The protein builders made of proteins and ribosomal RNA (rRNA) that read the genetic code in codons.

Start Codon

AUG is the signal that tells the ribosome where to begin and codes for the amino acid methionine.

Stop Codons

UAA, UAG, and UGA are signals that end the protein-building process and do not code for any amino acid.

Anticodon

A three-nucleotide sequence on tRNA that matches a specific mRNA codon.

A-site (Aminoacyl site)

The area in the ribosome where the incoming tRNA carrying its amino acid first docks.

P-site (Peptidyl site)

The site in the ribosome that holds the tRNA attached to the growing chain of amino acids.

E-site (Exit site)

The area from which the "empty" tRNA leaves the ribosome after dropping off its amino acid.

Peptide bond

The link formed between the new amino acid in the A-site and the growing chain in the P-site.

RNA Polymerase

The main enzyme that builds mRNA by unwinding DNA and adding complementary RNA nucleotides.

Promoter

A specific DNA sequence that signals RNA polymerase to bind and start transcription.

Template Strand

The DNA strand used as a guide by RNA polymerase to build the mRNA.

Coding Strand

The non-template DNA strand which has a sequence similar to the resulting mRNA, except for the use of Thymine (T) instead of Uracil (U).

Terminator

A DNA sequence that signals RNA polymerase to stop transcribing.

Pre-mRNA

The initial RNA transcript made in eukaryotic cells before processing.

5' Cap

A modified guanine nucleotide added to the beginning of pre-mRNA to help ribosomes attach.

Poly-A tail

A string of adenine nucleotides added to the end of mRNA to protect it and aid in translation.

Introns

Non-coding regions in eukaryotic pre-mRNA that are removed during splicing.

Exons

Coding regions in eukaryotic pre-mRNA that are joined together to form mature mRNA.

Mature mRNA

The processed mRNA that has been edited and is ready to leave the nucleus.