Genetics And Evolution- Molecular Basis Of Inheritance - Steps Of Initiation On Eukaryotes

Molecular Basis of Inheritance - Steps of Initiation on Eukaryotes

Inheritance: transfer of genetic information from parents to offspring
Genetics: study of heredity and variation in organisms
Evolution: change in inherited characteristics of populations over generations

Slide 2: DNA Structure

Deoxyribonucleic Acid (DNA) is a double-stranded molecule
Made up of nucleotides: sugar (deoxyribose), phosphate group, and nitrogenous base (adenine, thymine, guanine, cytosine)
Complementary base pairing: A-T and G-C

Slide 3: DNA Replication

Process by which DNA makes an exact copy of itself
Steps: initiation, elongation, and termination
Enzymes involved: helicase, DNA polymerase, DNA ligase

Slide 4: Transcription

Process of making a RNA molecule from a DNA template
Steps: initiation, elongation, and termination
RNA polymerase enzyme catalyzes the synthesis of RNA

Slide 5: Post-Transcriptional Modifications

Modifications made to the RNA molecule after transcription
Addition of a 5’ cap and a poly-A tail
RNA splicing removes introns and joins exons

Slide 6: Genetic Code

The set of rules by which information in the DNA sequence is converted into a protein
Codons: sequences of three nucleotides that code for amino acids
Start codon (AUG) initiates protein synthesis, stop codons (UAA, UAG, UGA) end protein synthesis

Slide 7: Translation

The process by which mRNA is decoded and a protein is synthesized
Occurs on ribosomes in the cytoplasm
Steps: initiation, elongation, and termination

Slide 8: Mutations

Permanent changes in the DNA sequence
Types: point mutations (substitution, insertion, deletion), frameshift mutations, chromosomal mutations
Can lead to genetic disorders or variation in populations

Slide 9: Recombinant DNA Technology

Techniques used to manipulate and study DNA in the laboratory
Applications: genetic engineering, gene cloning, gene therapy
Tools: restriction enzymes, DNA ligase, plasmids

Slide 10: Polymerase Chain Reaction (PCR)

Method used to amplify a specific DNA sequence
Steps: denaturation, annealing, and extension
Components: DNA template, primers, nucleotides, DNA polymerase

Slide 11: Gene Expression

Process by which information encoded in a gene is used to direct the synthesis of a functional gene product (protein or RNA molecule)
Steps: transcription and translation
Regulation of gene expression: control of when, where, and in what amount a gene is expressed

Slide 12: Regulation of Gene Expression

Gene regulation ensures that genes are expressed only when needed
Types of regulation: transcriptional, post-transcriptional, translational, and post-translational
Examples: gene regulatory proteins, enhancers, repressors

Slide 13: Genetic Variation

Differences in genetic makeup among individuals within a population
Sources of genetic variation: mutation, recombination, and gene flow
Importance of genetic variation in evolution and adaptation

Slide 14: Mendelian Genetics

Study of inherited traits and their patterns of transmission
Mendel’s laws: law of segregation and law of independent assortment
Punnett squares used to predict the inheritance of traits

Slide 15: Mendelian Inheritance of Traits

Dominant and recessive traits
Phenotype and genotype
Examples: Mendel’s pea plant experiments, human genetic disorders (e.g. cystic fibrosis, sickle cell anemia)

Slide 16: Non-Mendelian Inheritance

Inheritance patterns that do not follow Mendel’s laws
Incomplete dominance, codominance, and multiple alleles
Examples: blood types (A, B, AB, O), sickle cell trait

Slide 17: Sex-Linked Inheritance

Inheritance of traits linked to sex chromosomes
Examples: color blindness, hemophilia
Females are carriers while males are more likely to express the trait

Slide 18: Polygenic Inheritance

Inheritance of traits controlled by multiple genes
Produces a wide range of phenotypes
Examples: height, skin color, eye color

Slide 19: Human Genome Project

International scientific research project
Goal: to determine the complete sequence of the human genome
Benefits: understanding the genetic basis of diseases, personalized medicine, genetic counseling

Slide 20: Genetic Engineering

Manipulation of an organism’s genes to achieve desired traits or outcomes
Tools and techniques: recombinant DNA technology, gene editing (e.g. CRISPR-Cas9), genetic modification of crops
Applications: medical research, agriculture, biotechnology

Slide 21: Evolutionary Adaption

Evolutionary adaptation refers to the process through which species become better suited to their environment over time
Natural selection acts on variations within a population, favoring traits that increase an organism’s survival and reproductive success
Examples: camouflage, mimicry, antibiotic resistance

Slide 22: Speciation

Speciation is the process by which new species arise from existing ones
It occurs through reproductive isolation and genetic divergence
Types of speciation: allopatric, sympatric, and parapatric speciation

Slide 23: Mechanisms of Evolution

Evolution occurs through several mechanisms:
- Natural selection: differential survival and reproduction of individuals with advantageous traits
- Genetic drift: random changes in gene frequencies due to chance events
- Gene flow: movement of genes between populations through migration
- Mutation: changes in DNA sequence that introduce new genetic variation

Slide 24: Hardy-Weinberg Principle

Hardy-Weinberg equilibrium describes a situation in which allele frequencies in a population do not change over time
Conditions for Hardy-Weinberg equilibrium: no mutation, random mating, no natural selection, no genetic drift, no gene flow
Can be used to calculate allele frequencies and predict genotype frequencies in a population

Slide 25: Evolutionary Tree

An evolutionary tree, also known as a phylogenetic tree, depicts the evolutionary relationships between different species or groups of organisms
It shows the common ancestry and divergence of species over time
Branches represent lineages, and nodes represent common ancestors

Slide 26: Fossil Record

Fossils are preserved remnants or traces of organisms from the past
The fossil record provides evidence for the existence of extinct species and the evolution of current species
Fossil dating techniques: relative dating, radiometric dating

Slide 27: Comparative Anatomy

Comparative anatomy involves studying the anatomical similarities and differences among different species
Homologous structures: structures with similar origin but different function
Analogous structures: structures with different origin but similar function

Slide 28: Comparative Embryology

Comparative embryology studies the development of different organisms to identify similarities and differences in their embryonic stages
Embryos of different species often exhibit common developmental patterns, suggesting shared ancestry
Examples: pharyngeal arches in animals, tail development in humans

Slide 29: Molecular Phylogenetics

Molecular phylogenetics uses DNA or protein sequences to infer the evolutionary relationships between organisms
DNA sequencing techniques provide a molecular clock to estimate the divergence and evolutionary history of species
Examples: DNA barcoding, molecular clock analysis

Slide 30: Human Evolution

Human evolution is the study of the evolutionary history of the human species
Hominin fossils provide evidence for the gradual development of human-like traits over time
Examples: hominin species (Homo habilis, Homo erectus, Homo neanderthalensis)