Define analogous structure.
Structures that serve similar functions but evolved independently in different lineages
They arise due to convergent evolution.
What are homeotic genes?
Master regulator genes that control the development of anatomical structures in animals, plants, and fungi
They play a crucial role in embryonic development.
Define homologous structure.
Body parts that appear similar in separate lineages because they evolved in a common ancestor
They provide evidence for divergent evolution.
What is a vestigial structure?
Body parts that no longer have a function, such as tail bones and muscles for moving the ears in humans
They are remnants of evolutionary history.
What does developmental evidence suggest about closely related animals?
The more closely related animals are, the more similar their development is
This is coordinated by layers of master gene expression.
What are Hox genes?
Subsets of homeotic genes that direct the head-to-tail formation of body segments during embryonic development
They are crucial for proper body plan formation.
Define convergent evolution.
Process where organisms with different ancestries adapt in similar ways to similar environmental demands
This results in analogous structures.
Define divergent evolution.
Process where closely related species accumulate differences over time, leading to distinct traits and potentially new species
Often due to adaptation to different environments or niches.
What are neutral mutations?
Mutations that have no effect on an individual’s survival or reproduction
They contribute to genetic diversity without impacting fitness.
What can similarities in nucleotide sequences of shared genes indicate?
They can be used to study shared ancestry
This is a key method in genetic evidence for evolution.
What are pseudogenes?
Copies of genes that exist elsewhere in the genome but no longer produce a functional protein
They can reveal information about ancient genes and gene duplication rates.
What is the significance of mitochondrial DNA?
It is inherited intact from only one parent in most animals
It provides insights into maternal lineage and evolutionary relationships.
What does the cytochrome-b gene help scientists study?
The evolution of species, such as lizards in the Canary Islands
It is used to determine genetic differences and relationships between species.
True or false: The more similar two genomes are with respect to nucleotide sequences, the more closely related the organisms are.
TRUE
This principle is fundamental in DNA sequencing for evolutionary studies.
