All flashcards
Flashcard 1: What is the best inference when embryonic development patterns are very different between two species?
Answer: They are likely more distantly related. Different embryonic patterns suggest separate evolutionary paths.
Flashcard 2: What is a homologous embryonic structure?
Answer: A shared embryonic feature inherited from a common ancestor. These structures develop from the same ancestral blueprint.
Flashcard 3: What is an analogous structure (not evidence of close relationship) in evolution?
Answer: A similar feature that evolved independently (convergent evolution). Similar appearance but different evolutionary origins.
Flashcard 4: Which embryonic feature in vertebrates is commonly used as evidence of shared ancestry: pharyngeal pouches or petals?
Answer: Pharyngeal pouches. All vertebrate embryos develop these gill-like structures.
Flashcard 5: Which embryonic feature in vertebrates is commonly compared to infer relatedness: tails or chloroplasts?
Answer: Tails. Vertebrate embryos share tail development; plants lack tails.
Flashcard 6: What does the presence of similar pharyngeal pouches in vertebrate embryos suggest?
Answer: Shared ancestry among vertebrates. This embryonic trait links all vertebrates to common ancestors.
Flashcard 7: Which option best describes why embryological evidence supports evolution?
Answer: It reveals inherited developmental patterns from ancestors. Embryos retain ancestral features lost in adult forms.
Flashcard 8: Identify the best match: more similar embryos in early development means what relationship?
Answer: Closer evolutionary relationship. More shared embryonic traits indicate recent common ancestry.
Flashcard 9: Which pair is most closely related if embryos A and B share more early-stage traits than A and C?
Answer: A and B. Shared traits indicate A and B diverged more recently.
Flashcard 10: Choose the correct inference: two embryos share a tail bud and pharyngeal pouches in early stages.
Answer: They likely share a common vertebrate ancestor. These are defining features of vertebrate embryos.
Flashcard 11: Identify the stronger evidence for close relationship: similar embryos early or similar adults only?
Answer: Similar embryos early. Early similarities reflect true evolutionary relationships.
Flashcard 12: Which statement is correct: embryological similarities are most meaningful when they occur at what stage?
Answer: Early developmental stages. Ancestral features appear before species-specific traits develop.
Flashcard 13: What is the main limitation of using embryology alone to infer relationships among species?
Answer: It should be combined with DNA and fossil evidence. Multiple evidence types provide more accurate relationships.
Flashcard 14: What is comparative embryology used for in evolutionary biology?
Answer: Using embryo development similarities to infer relatedness. Similar embryonic development patterns indicate evolutionary relationships.
Flashcard 15: Which conclusion is supported when two species share many early embryonic structures?
Answer: They likely share a more recent common ancestor. Similar embryonic features are inherited from shared ancestors.
Flashcard 16: Which embryological comparison is most useful for inferring evolutionary relationships: early stages or adult traits?
Answer: Early embryonic stages. Early stages show ancestral traits before divergence occurs.
Flashcard 17: What is the typical adult fate of pharyngeal pouches in humans?
Answer: Parts of the ear, jaw, and throat (not gills). In land vertebrates, these pouches form non-respiratory structures.
Flashcard 18: What is the embryonic tail in many vertebrates evidence of?
Answer: Shared vertebrate ancestry. All vertebrates descend from tailed ancestors.
Flashcard 19: Which group is best supported as closely related if their embryos share neural tube, notochord, and pharyngeal pouches?
Answer: Vertebrates (chordates). These three structures are defining features of chordate embryos.
Flashcard 20: Which embryonic structure in vertebrates develops into the spinal cord and brain?
Answer: Neural tube. Forms from dorsal ectoderm and becomes the central nervous system.
Flashcard 21: Identify the relationship: Species A and B embryos share more traits than A and C. Who is closer to A?
Answer: Species B. More shared traits indicate closer evolutionary relationship.
Flashcard 22: What does it mean if two species share many embryonic homologous structures?
Answer: They are more closely related evolutionarily. More shared features indicate more recent common ancestor.
Flashcard 23: What is embryology as evidence for evolution?
Answer: Study of embryos used to compare development and infer relatedness. Compares developmental stages to determine evolutionary relationships.
Flashcard 24: What does it suggest when two species have very similar early embryos?
Answer: They likely share a recent common ancestor. Similar early development indicates shared evolutionary history.
Flashcard 25: Which developmental stage is usually most useful for comparing relatedness: early, middle, or late?
Answer: Early embryonic stages. Early stages show most ancestral features before specialization.
Flashcard 26: What is the term for a shared embryonic structure inherited from a common ancestor?
Answer: Homologous structure. Same embryonic origin indicates shared ancestry.
Flashcard 27: Which option best indicates close relationship: similar adult forms or similar embryonic patterns?
Answer: Similar embryonic patterns. Embryonic similarities reveal deeper evolutionary connections.
Flashcard 28: What is a pharyngeal pouch (pharyngeal arch) in vertebrate embryos?
Answer: A throat-region fold that develops into different adult structures. Present in all vertebrate embryos, showing common ancestry.
Flashcard 29: In fish, what do pharyngeal pouches typically develop into?
Answer: Gills or gill-support structures. Fish retain these structures for breathing underwater.
Flashcard 30: In humans, what do pharyngeal pouches typically develop into?
Answer: Parts of the jaw, ear, and throat. Same embryonic structures repurposed for different functions.