All flashcards
Flashcard 1: Identify the best conclusion: Species A and B embryos differ greatly at all stages that were compared.
Answer: A and B are likely less closely related. Different embryonic development suggests more distant evolutionary relationship.
Flashcard 2: What does it mean if two species share more embryonic similarities than either shares with a third species?
Answer: The two species are more closely related. More shared traits indicate more recent common ancestry.
Flashcard 3: Which embryonic feature in vertebrates commonly supports relatedness: a post-anal tail or a placenta?
Answer: A post-anal tail. This structure appears in all vertebrate embryos, indicating shared ancestry.
Flashcard 4: Which embryonic feature in vertebrates is often cited as evidence of relatedness: gill slits (pharyngeal pouches) or wings?
Answer: Gill slits (pharyngeal pouches). All vertebrate embryos develop these pouches, revealing common ancestry.
Flashcard 5: What is the key difference between homologous and analogous structures in embryo comparisons?
Answer: Homologous share ancestry; analogous share function only. Homology indicates evolutionary relationship; analogy indicates convergent evolution.
Flashcard 6: What is a homologous structure in embryology?
Answer: A shared developmental structure inherited from a common ancestor. These structures develop from the same embryonic tissue due to common ancestry.
Flashcard 7: Which developmental stage is usually most useful for detecting shared ancestry: early or late embryonic stages?
Answer: Early embryonic stages. Early stages show ancestral traits before species-specific features develop.
Flashcard 8: What is the main embryological claim that supports common ancestry among species?
Answer: Similar early embryos suggest shared ancestry. Species with common ancestors develop similarly in early stages.
Flashcard 9: What is embryology as used in evolutionary biology evidence?
Answer: Study of embryo development used to compare species. Comparing embryonic stages reveals evolutionary relationships between organisms.
Flashcard 10: Which statement correctly uses embryology to support relatedness between two vertebrates?
Answer: Similar early embryos indicate a shared ancestor. This principle connects embryonic similarities to evolutionary relationships.
Flashcard 11: Identify the best evidence type: Similarities in adult body shape or similarities in embryo segmentation patterns?
Answer: Similarities in embryo segmentation patterns. Embryonic patterns reveal ancestry better than adult forms.
Flashcard 12: Which option is an embryology-based inference: 'shared DNA' or 'shared developmental pathways'?
Answer: Shared developmental pathways. Embryology studies development patterns, not DNA directly.
Flashcard 13: What is a vestigial structure as inferred from embryonic development?
Answer: A reduced trait inherited from ancestors, often seen forming in embryos. These non-functional remnants appear during development, revealing ancestry.
Flashcard 14: Identify the best claim supported by embryos: Snake embryos form limb buds that later regress.
Answer: Snakes descended from limbed ancestors. Temporary limb buds reveal snakes evolved from four-legged ancestors.
Flashcard 15: Identify the best claim supported by embryos: Human and fish embryos both show pharyngeal pouches early.
Answer: Humans and fish share a vertebrate ancestor. Pharyngeal pouches in both species indicate common vertebrate ancestry.
Flashcard 16: What is the strongest embryological evidence of relatedness: shared early structures or shared learned behaviors?
Answer: Shared early developmental structures. Embryonic structures are inherited; behaviors are often learned.
Flashcard 17: Which comparison best supports close relatedness: similar early embryos or similar adult habitats?
Answer: Similar early embryos. Embryonic similarities reveal evolutionary relationships; habitats don't.
Flashcard 18: Which embryonic pattern most strongly suggests relatedness: shared early structures or shared adult habitats?
Answer: Shared early embryonic structures. Inherited structures indicate ancestry; habitats can be coincidental.
Flashcard 19: Which option best supports relatedness: embryos share the same early limb buds or adults share the same diet?
Answer: Embryos share the same early limb buds. Limb buds are inherited structures; diet is environmental.
Flashcard 20: What is the neural tube in a vertebrate embryo?
Answer: A structure that develops into the brain and spinal cord. Forms from folding neural plate in all vertebrates.
Flashcard 21: What is the notochord in a chordate embryo?
Answer: A flexible supporting rod along the back. Present in all chordates; becomes spine in vertebrates.
Flashcard 22: Which group is best supported by embryological evidence showing a notochord: vertebrates or flowering plants?
Answer: Vertebrates (chordates). Notochords are defining features of chordate embryos.
Flashcard 23: In many vertebrate embryos, what does the presence of a post-anal tail suggest?
Answer: Shared ancestry among vertebrates. All vertebrates develop tails early, even if lost later.
Flashcard 24: What is a pharyngeal pouch in vertebrate embryos?
Answer: A throat-region structure that can form gills or ear parts. These pouches develop differently in fish (gills) vs mammals (ears).
Flashcard 25: What is the key difference between homologous and analogous structures?
Answer: Homologous share ancestry; analogous share function only. Homology indicates evolutionary relationship; analogy is convergent evolution.
Flashcard 26: What is a homologous embryonic structure?
Answer: An embryonic feature inherited from a common ancestor. These structures develop from the same ancestral blueprint.
Flashcard 27: Identify the best conclusion if species A and B embryos are similar early but differ later in development.
Answer: They share ancestry but diverged as development progressed. Early similarities followed by divergence shows evolutionary branching.
Flashcard 28: What is embryological evidence in evolution?
Answer: Similarities in embryos used to infer common ancestry. Comparing developmental stages reveals evolutionary relationships.
Flashcard 29: What is the main claim supported when embryos of two species are very similar early on?
Answer: The species likely share a recent common ancestor. Similar early development indicates shared evolutionary origin.
Flashcard 30: Which term describes similarities due to common ancestry: homology or analogy?
Answer: Homology. Homologous structures share evolutionary origin, not just function.