Topic 4 - Genetic Information Flashcards
Eukaryotic DNA
Linear DNA associated with histone proteins.
Prokaryotic DNA
Circular DNA not associated with proteins.
Introns
Non-coding regions within genes.
Exons
Coding regions of genes that produce proteins.
Genome
Complete set of genes in a cell.
Proteome
Complete set of proteins expressed by a cell.
Complementary bases
Pairing of bases allows DNA replication.
Double-stranded DNA
Structure that enables stable information storage.
Hydrogen bonds in DNA
Weak bonds allowing DNA strands to separate.
Triplet code
Three bases coding for a single amino acid.
Universal genetic code
Same triplet codes for amino acids across organisms.
Non-overlapping genetic code
Each base is read only once in coding.
Degenerate genetic code
Most amino acids have multiple coding triplets.
Functional RNA
RNA molecules that perform roles without coding proteins.
Transcription
Process of synthesizing RNA from DNA template.
RNA polymerase
Enzyme that forms RNA by linking nucleotides.
Pre-mRNA
Initial RNA transcript before splicing occurs.
Splicing
Removal of introns and joining of exons.
Nuclear pore
Channel through which pre-mRNA exits the nucleus.
Ribosomal RNA
RNA component of ribosomes for protein synthesis.
Transfer RNA
RNA that transports amino acids to ribosomes.
Helicase enzyme
Unwinds DNA by breaking hydrogen bonds.
Sugar-phosphate backbone
Strong structure protecting DNA’s weak hydrogen bonds.
Mitochondrial DNA
Circular DNA found in mitochondria, similar to prokaryotes.
Chloroplast DNA
Circular DNA in chloroplasts, resembling prokaryotic DNA.
mRNA
Messenger RNA that carries genetic information.
tRNA
Transfer RNA that brings amino acids to ribosomes.
Codon
Three-base sequence on mRNA coding for amino acid.
Anticodon
Three-base sequence on tRNA complementary to codon.
Peptide bond
Covalent bond linking amino acids in proteins.
ATP
Energy molecule used in biochemical reactions.
Ribose sugar
Sugar component in RNA nucleotides.
Deoxyribose sugar
Sugar component in DNA nucleotides.
Mutation
Change in base sequence of a gene.
Substitution mutation
Replacement of one base with another.
Deletion mutation
Removal of a base causing frame shift.
Allele
Different form of a gene.
Genetic code
Set of rules for translating mRNA to proteins.
Silent mutation
Mutation that does not affect amino acid sequence.
Meiosis
Cell division producing gametes with half chromosome number.
Diploid
Cell with two sets of chromosomes (2n).
Haploid
Cell with one set of chromosomes (n).
Homologous chromosomes
Chromosome pairs with same genes, different alleles.
Bivalents
Paired homologous chromosomes during meiosis.
Crossing-over
Exchange of DNA segments between homologous chromosomes.
Independent segregation
Random distribution of maternal and paternal chromosomes.
Sister chromatids
Identical copies of a chromosome joined at centromere.
Centromere
Region where sister chromatids are joined.
Spindle fibres
Structures that separate chromatids during cell division.
Genetic diversity
Variability in genetic makeup within a population.
Mutagenic agents
Factors that increase mutation frequency, e.g., radiation.
High energy radiation
Radiation like X-rays that can cause mutations.
Benzene
Chemical compound known to be mutagenic.
Primary structure
Sequence of amino acids in a protein.
Tertiary structure
3D shape of a protein determined by folding.
Independent segregation
Leads to varied combinations of alleles in gametes.
Gametes
Reproductive cells containing maternal and paternal alleles.
Chromosome pairs
Humans have 23 pairs of chromosomes.
Genetically different gametes
Humans can produce 2^23 unique gametes.
Zygote combinations
246 different chromosome combinations in a zygote.
Crossing over
Rare event creating new allele combinations during meiosis.
Chromosome abnormalities
Changes in chromosome number affecting genetic outcomes.
Non-disjunction
Chromatids fail to separate during meiosis.
Down syndrome
Result of zygote with three copies of a chromosome.
Genetic diversity
Variety of different alleles in a population.
Natural selection
Process favoring advantageous traits in a population.
Mutations
Changes in DNA creating different alleles.
Advantageous alleles
Alleles that enhance survival and reproduction.
Allele frequency
Proportion of a specific allele in a population.
Antibiotics
Substances that kill or inhibit bacterial growth.
Bacterial cell wall
Structure targeted by antibiotics like penicillin.
Osmotic lysis
Cell death due to pressure from water absorption.
Antibiotic resistance
Bacteria’s ability to survive despite antibiotic presence.
Penicillinase
Enzyme that breaks down penicillin, causing resistance.
Decreased permeability
Reduced ability of antibiotics to enter bacterial cells.
Random mutations
Spontaneous genetic changes leading to resistance.
Sensitive bacteria
Bacteria susceptible to the effects of antibiotics.
Resistant bacterium
Bacterium that survives antibiotic treatment and reproduces.
Daughter cells
Cells produced from the division of a resistant bacterium.
Widespread antibiotic use
Increased selection for resistant bacterial strains.
Resistant strain
Bacteria that survive antibiotic treatment.
Antibiotic resistance
Ability of bacteria to resist effects of antibiotics.
Selective advantage
Benefit that allows survival and reproduction.
Directional selection
Favors one extreme phenotype over others.
Stabilising selection
Favors average phenotypes, reducing variation.
Antibiotic course completion
Patients must finish prescribed antibiotics.
Combination therapy
Using multiple antibiotics to prevent resistance.
Penicillinase enzyme
Enzyme that inactivates penicillin antibiotics.
Taxonomy
Classification of organisms into hierarchical groups.
Taxon
Group of organisms in taxonomy.
Domain
Highest taxonomic rank, e.g., Eukaryote.
Kingdom
Second highest taxonomic rank, e.g., Animalia.
Phylum
Group of related classes in taxonomy.
Class
Group of related orders in taxonomy.
Order
Group of related families in taxonomy.
Family
Group of related genera in taxonomy.
Genus
Group of closely related species.
Species
Group of organisms that can breed.
Binomial nomenclature
Two-word naming system for species.
Phylogeny
Study of evolutionary relationships among organisms.
Common ancestor
An organism from which others evolved.
Antibiotic use limitation
Restricting antibiotics for minor infections.
Resistant alleles
Genetic variants that confer antibiotic resistance.
Infectious outbreak
Spread of disease caused by resistant bacteria.
Long-term antibiotic treatment
Prolonged use leading to resistance development.
Birth weight selection
Stabilizing selection example in human infants.
Surface area:volume ratio
Influences heat loss in organisms.
Common Ancestor
An ancestor shared by closely related species.
Genus
A group of closely related species.
Family
A group of related genera sharing a common ancestor.
Order
A classification above family, grouping related families.
Observable Features
Physical traits used in early taxonomy.
Molecular Biology
Study of biological processes at a molecular level.
DNA Sequencing
Determining the exact sequence of nucleotides in DNA.
Cytochrome c Gene
A gene crucial for respiration, found in eukaryotes.
Base Sequence Similarity
Closer sequences indicate closer evolutionary relationships.
Amino Acid Sequence
Determined by base sequences, reflects evolutionary closeness.
Immunological Comparison
Testing blood proteins for evolutionary relationships.
Antibodies
Proteins produced by the immune system to fight antigens.
Precipitation Reaction
Formation of a solid when antibodies bind to antigens.
Behaviour Patterns
Similar behaviors observed within the same species.
Courtship Displays
Behaviors to attract mates and recognize species.
Hybrid Infertility
Offspring of different species are often infertile.
Gamete Production
Process stimulated by hormones during courtship.
Pair Bond Formation
Development of a strong connection between mating individuals.
Sexual Selection
Natural selection favoring traits that enhance mating success.
Advantageous Alleles
Genetic traits that improve reproductive success.
Courtship Signals
Displays used to attract mates, vary by species.
Pheromones
Chemical signals used for communication in mating.
Natural Selection
Process where advantageous traits become more common.
Evolutionary Relationships
Connections between species based on shared ancestry.
Environmental Influence
External factors affecting observable features in organisms.
Molecular Similarity
Genetic closeness inferred from DNA and protein analysis.
Species Recognition
Identifying members of the same species through behavior.
Biodiversity
Variety of life forms in ecosystems.
Species richness
Count of different species in a community.
Diversity index
Measures species diversity considering population sizes.
Diversity index formula
Diversity index = N(N-1) / Σn(n-1).
N in diversity index
Total organisms across all species.
n in diversity index
Total organisms of each specific species.
Higher diversity index
Indicates greater species diversity in habitat.
Plant diversity impact
More plant species leads to varied animal habitats.
Agricultural land impact
Lower plant variety due to monoculture practices.
Weedkillers effect
Eliminate native plants, reducing biodiversity.
Pesticides effect
Harmful to insect populations, affecting food webs.
Conservation techniques
Methods to protect species and habitats from extinction.
Setting aside land
Preserving areas for natural growth and biodiversity.
National Parks
Protected areas to maintain species diversity.
Quantitative investigation
Measurement of variation in species populations.
Sample size importance
Larger samples yield more reliable statistical results.
Random selection
Method to avoid bias in sample collection.
Standard deviation
Measures data spread around the mean.
Significance of overlap
Overlapping standard deviations indicate non-significant differences.
