Gene Control and Molecular Biology Principles

These flashcards cover key vocabulary and concepts related to gene control, molecular biology, and evolutionary principles.

Transcriptional control

The primary mechanism for gene control in prokaryotes.

mRNA sequence

5'-AUGCCGGGAUUUCGU-3' produces the amino acid sequence Met-Pro-Gly-Phe-Arg.

Transcription

The synthesis of RNA from a DNA template.

Translation

The synthesis of protein from mRNA.

Splicing

The removal of introns from pre-mRNA.

Peptide Bond Formation

The linking of amino acids in a protein chain.

Chromatin structure

Tightly packed chromatin prevents gene transcription.

Amino acid composition

Amino acids are made of an amino group, carboxyl group, and side chain.

Amino acid side chains

The size and polarity of side chains make proteins different from each other.

Hydrophobic amino acids

Amino acids that are nonpolar.

Central Dogma

The biological concept that defines the flow of genetic information: DNA -> RNA -> Protein.

Ribosomes

Cell structures that read mRNA and synthesize proteins.

Codons

Sequences of three nucleotides in mRNA.

Possible codons

A total of 64 codons can exist based on the genetic code.

Frameshift mutation

An addition or deletion of nucleotides that alters the genetic sequence.

Degenerate code

The genetic code where multiple codons can code for the same amino acid.

Effects of frameshift mutation

Can result in nonfunctional proteins or halt protein synthesis.

Promoters

Regions where RNA polymerase binds to start transcription.

Transcription in prokaryotes

Transcription occurs simultaneously with translation.

RNA synthesis direction

RNA is synthesized in the 5' to 3' direction.

RNA Polymerase I

Enzyme that transcribes rRNA genes in eukaryotes.

Transcription factors

Proteins that help RNA Polymerase bind to the promoter.

5' methylguanosine cap

Added to the 5' end of eukaryotic mRNA for protection.

Poly A Tail

Added to protect mRNA from degradation.

Spliceosomes

Complexes made of proteins and snRNA involved in splicing.

Population bottleneck

Genetic similarities in modern species, like cheetahs, due to historical population declines.

Gradual equilibrium

Description of evolutionary change as slow and steady over long time periods.

Hardy-Weinberg principle

States that allele and genotype frequencies remain constant in absence of evolution.

Pre-translation mRNA processing

Involves mRNA splicing and capping.

tRNA function

Carries amino acids to the ribosome during translation.

Darwin's study focus

Beak shape and size in finches as adaptations.

Genomics

The study of whole genomes.

Theory of evolution as fact

Misunderstanding; a scientific theory is a well-supported explanation.

Antibiotics from biotech

Designed to prevent and treat bacterial infections.

RNA Polymerase II

Enzyme responsible for transcribing protein-coding genes.

Introns after processing

Introns are spliced out before translation.

First cloned animal

The first cloned animal was a sheep.

Mutation effects on stop codons

Changes can lead to longer proteins than normal.

Theory of Natural Selection

States that individuals with traits better suited to the environment will survive and reproduce.

Anticodon function

Recognizes and pairs with the corresponding codon during protein synthesis.

Selective pressure

Environmental factors that affect survival and reproduction.

Darwin's book

On the Origin of Species.

Ribosomal functions

Two main functions: translation and protein synthesis.

Function of small ribosomal unit

Binds to the start codon and tRNA.

Introns post-processing

Introns are removed after mRNA processing.

Post-zygotic isolation

Reduces reproduction or fertility in hybrid species.

Malthus influence on Darwin

Malthus' work inspired Darwin and Wallace.

DNA movement in gel electrophoresis

DNA moves toward the positive pole.

Sum of allele frequencies

In a population, the total equals 1.

DNA fragment separation method

Gel electrophoresis is used to separate and identify DNA fragments.

Allopatric speciation

Occurs when physical barriers divide populations, creating new species.

Punctuated equilibrium

Evolutionary changes characterized by periods of stability interrupted by rapid change.

Gel electrophoresis separation

Separates DNA by size through an electric field gel matrix.

DNA size visibility in gel

Requires a DNA ladder to determine size of molecules.

Faint bands in gel

Use a more concentrated DNA sample or re-stain the gel.

FACT complex function

Facilitates the formation of nucleosomes.

Lysis buffer in extraction

Breaks down cell membranes during DNA extraction.

Analogous structures

Body parts with similar functions but different appearances.

Translation stages

Initiation, elongation, termination are the three main stages.

Fossil record and evolution

Evidence shows species appear, change, and go extinct over time.

Pangea breakup and biogeography

Allowed for different species development in isolated regions.

Reproductive isolation

Barriers preventing reproduction between two populations.

H-W conditions rarely met explanation

Natural populations are influenced by mutations, selections, migrations, and genetic drift.

Cellular respiration process

Cells extract energy from food.

Stop codon effects on translation

Translation ends and the protein is released.

Lysis process in extractions

Breaks down cell membranes during DNA extractions.

Electron role in glucose breakdown

Transfers energy.

GMO characteristics

Has DNA from different species.

DNA fragment visualization

Uses staining dyes and UV light during gel electrophoresis.

Genetic map definition

Indicates the location of genes on chromosomes.

DNA fingerprinting function

Matches DNA samples with individuals in forensics.

Sympatric speciation

New species arise within the same geographic area.

Convergent evolution example

Similar body structures of whales and sharks due to similar environmental pressures.

Pre-zygotic isolation definition

Blocks fertilization between species.

Amino acid transformation in protein formation

Amino acids lose water during protein synthesis.

Temporal isolation occurrence

Breeding occurs at different times or seasons.

Microevolution definition

Small genetic changes in a population over time.

Mutation importance in evolution

Creates genetic variation necessary for evolution.

Evolution without natural selection

Yes, evolution can occur without it.

Behavioral isolation example

Mating calls attract only the same species.

Heterozygous frequency prediction

Given p=0.7 and q=0.3, the frequency is 0.42.

Genetic drift

Random changes in allele frequencies within a population.

Start codon for protein synthesis

AUG.

Peptidyl transferase function

Enzyme that binds amino acids during translation.

PCR use

To amplify DNA segments.

Biotechnology use

Modify genetic material of living organisms.

Divergent evolution definition

Two species evolve from a common ancestor.

Homologous structures definition

Body parts that share a common ancestry.

Darwin's contemporaries

No, he was not the only naturalist at the time.

Biotechnology definition

The use of living organisms to create useful products.

Population allele frequencies matching H-W

Indicates no evolution is occurring.

Plasmid definition

A small circular DNA molecule used in cloning.

Recombinant DNA definition

DNA that has been cut and reassembled.

Larger gene pools adaptability

Better adaptation due to increased genetic variation.

Molecular biology and evolution

Shows closely related species share similar DNA/protein sequences.

Adaptive radiation definition

Rapid diversification of many species from a single ancestor.

Rho-dependent termination signal

One type of signal that ends transcription.

Evolutionary response statement

False; evolution does not always respond directly.

Speciation definition

The formation of a new species from an ancestral population.

Biogeography study focus

Geographic distribution of living and extinct species.