The Central Dogma Study Guide Flashcards

Vocabulary flashcards covering key concepts from the study guide on the Central Dogma, nucleic acid structures, information flow processes, RNA types, translation, and types of mutations.

Central Dogma

The core concept that genetic information generally flows in a single direction from DNA to RNA to protein.

Nucleotide

The basic building block of nucleic acids, consisting of a sugar, a phosphate group, and a nitrogenous base.

DNA vs. RNA Comparison Table

A summary chart contrasting DNA (deoxyribose, double-stranded double helix, thymine) and RNA (ribose, single-stranded, uracil).

Purines

Double-ring nitrogenous bases consisting of adenine (A) and guanine (G).

Pyrimidines

Single-ring nitrogenous bases consisting of cytosine (C), thymine (T), and uracil (U).

Antiparallel

The arrangement of DNA strands running in opposite directions, where one strand runs $5'$ to $3'$ and the complement runs $3'$ to $5'$.

Information-Flow Processes Table

A table summarizing the pathways of genetic information: replication ($\text{DNA} \rightarrow \text{DNA}$), transcription ($\text{DNA} \rightarrow \text{RNA}$), reverse transcription ($\text{RNA} \rightarrow \text{DNA}$), and translation ($\text{RNA} \rightarrow \text{protein}$).

DNA Replication (process)

The process occurring during the S phase of the cell cycle in which a copy of DNA is synthesized to ensure daughter cells receive identical genetic material.

Semiconservative Replication

The model of DNA replication in which each newly formed DNA molecule consists of one original parent strand and one newly synthesized strand.

Sister Chromatids

Two identical copies of a single chromosome produced after DNA replication.

Transcription

The process of synthesizing an RNA strand from a DNA template strand.

Template Strand

The specific DNA strand used during transcription to build a complementary RNA strand.

Coding Strand

The non-template DNA strand whose sequence matches the generated mRNA sequence (except thymine is replaced by uracil in mRNA).

Reverse Transcription

The synthesis of DNA from an RNA template, utilized by retroviruses such as HIV.

mRNA (messenger RNA)

Type of RNA that carries genetic instructions from DNA as three-base codons to specify amino acid sequences.

rRNA (ribosomal RNA)

Type of RNA that combines with proteins to construct ribosomes, the structural sites of protein synthesis.

tRNA (transfer RNA)

Type of RNA that carries a specific amino acid and has an anticodon that pairs with a complementary mRNA codon.

Codon

A three-base sequence on mRNA that specifies a particular amino acid or a signal to stop translation.

Anticodon

A three-base sequence on a tRNA molecule that base-pairs with a complementary codon on mRNA.

Translation

The process occurring at a ribosome where the nucleotide sequence of mRNA is converted into an amino-acid sequence to form a protein.

Degenerate Genetic Code

The characteristic of the genetic code in which more than one codon can code for the same amino acid.

Start Codon (AUG)

The specific mRNA codon (AUG) that initiates translation and specifies the amino acid methionine.

Stop Codons

UAA, UAG, UGA, that terminate protein translation when reached by a ribosome.

Point Mutation

A genetic mutation involving a change in a single base pair of DNA.

Silent Mutation

A point mutation that changes a codon sequence without altering the resulting amino acid.

Missense Mutation

A point mutation that alters a codon so that it codes for a different amino acid, such as the glutamic acid-to-valine substitution in sickle-cell anemia.

Nonsense Mutation

A point mutation that creates a premature stop codon, causing translation to end early and usually producing a nonfunctional protein.

Frameshift Mutation

A mutation caused by the insertion or deletion of nucleotide bases, which shifts the triplet reading frame and alters every subsequent codon.

DNA bases

adenine (A), thymine (T), cytosine (C), and guanine (G)

RNA bases

adenine (A), uracil (U), cytosine (C), and guanine (G)

DNA shape

double helix

A & G ring structure

double ring structure, called purines

C, T, and U ring structure

single ring structure, called pyrimidines

RNA shape

cloverleaf

DNA ends

3’ with an OH and 5’ with a phosphate

nucleotide joined by

phosphate of one nucleotide joins to OH of other nucleotide

A pairs with (DNA)

T in DNA - by means of hydrogen bonds

A pairs with (RNA)

U in RNA - by means of hydrogen bonds

C pairs with (DNA&RNA)

G in DNA and RNA - by means of hydrogen bonds.

DNA strand orientation

antiparallel

Replication

DNA → DNA, a copy of DNA is made

Transcription

DNA → RNA, RNA strand is made from DNA template

Reverse Transcription

RNA → DNA, DNA is made from RNA; used by retroviruses (HIV)

Translation

RNA → protein, polypeptide/protein is assembled from mRNA template during protein synthesis.

R

ribose

D

deoxyribose

P

phosphate

A

adenine

G

guanine

C

cytosine

T

thymine

U

uracil

OH

hydroxyl group

H

hydrogen atom

mRNA

messenger RNA, contains message from DNA, in form of codons, codons translated into amino acids in the protein

rRNA

ribosomal RNA, w/ proteins make up ribosomes

ribosomes

site of protein synthesis

tRNA

transfer RNA, contains anticodon from amino acid, translates nucleotide lang. to amino acid lang.

RNA complete →

migrates out of nucleus into cytoplasm, combines w/ribsomes

ribosome site

where protein synthesis happens

Phe

phenylalanine

phenylalanine

UUU, UUC

Leu

Leucine

Leucine

CUU, CUC, CUA, CUG

Ile

Isoleucine

Isoleucine

AUU, AUC, AUA.

Met

Methionine

Methionine (code)

start codon AUG

Val

Valine

Valine

GUU, GUC, GUA, GUG

Ser

Serine

Serine

UCU, UCC, UCA, UCG, AGU, AGC

Pro

Proline

Proline

CCU, CCC, CCA, CCG

Thr

Threonine

Threonine

ACU, ACC, ACA, ACG

Ala

Alanine

Alanine

GCU, GCC, GCA, GCG

Lys

Lysine

Lysine

AAA, AAG

Asn

Asparagine

Asparagine

AAU, AAC

His

Histidine

Histidine

CAU, CAC

Gln

Glutamine

Glutamine

CAA, CAG

Tyr

Tyrosine

Tyrosine

UAU, UAC

Cys

Cysteine

Cysteine

UGU, UGC

Trp

Tryptophan

Tryptophan

UGG

Arg

Arginine

Arginine

CGU, CGC, CGA, CGG, AGA, AGG

Gly

Glycine

Glycine

GGU, GGC, GGA, GGG