Bio Buddy Exam 3
.docx
School
University of Kentucky**We aren't endorsed by this school
Course
BIO 148
Subject
Biology
Date
Dec 18, 2024
Pages
3
Uploaded by MagistrateNewt2919
Mitosis:Purpose: To produce two genetically identical daughter cells for growth and repair.Meiosis:Purpose: To produce four genetically diverse haploid cells (gametes) for sexual reproduction.Meiosis I: Homologous chromosomes separate.Prophase I: Homologous chromosomes pair up and exchange segments (crossing over).Metaphase I: Homologous pairs align at the equator.Anaphase I: Homologous chromosomes are pulled to oppositepoles.Telophase I: Two haploid cells form.Meiosis II: Sister chromatids separate.Prophase II: Chromosomes condense again.Metaphase II: Chromosomes align at the equator.Anaphase II: Sister chromatids are pulled apart.Telophase II: Four haploid cells form.Inheritance Patterns:Autosomal Dominant: Only one copy of the dominant allele is needed for the trait to be expressed.Autosomal Recessive: Two copies of the recessive allele are needed for the trait to be expressed.Sex-Linked Traits: Traits associated with genes located on sex chromosomes (e.g., X-linked recessive traits).NaturalSelection:Definition: A processwhereorganismsbetteradapted totheirenvironment tend to survive and produce more offspring. This concept was introduced by Charles Darwin.Mechanism: Variations in traits exist within a population. Traits that enhance survival and reproduction become more common in subsequent generations.Adaptation:Definition: A trait shaped by natural selection that increases an organism's fitness in its environment.Types: Structural (e.g., beak shapein birds), behavioral (e.g., migration), and physiological (e.g., antifreeze proteins in Arctic fish).Speciation and Genetic DriftSpeciation:Definition: The formation of new and distinct species during evolution.Types: Allopatric Speciation: Occurs when populations are geographically separated.Sympatric Speciation: Occurs without geographical separation, often through genetic mutations or behavioral changes.Genetic Drift:Definition: Random changes in allele frequencies in a population, which can lead to significant geneticchangesover time.Effects: Bottleneck Effect: A sharp reduction in population size due to environmental events, leading to a loss of genetic diversity.Founder Effect: When a new population is established by a smallnumber of individuals, leading to reduced genetic variation.
