Molecular Biology Evidence for Evolution practice quiz

🧬 Topic Summary

Molecular biology provides compelling evidence for evolution by examining the similarities and differences in the genetic material (DNA and RNA) and proteins of different organisms. Conserved sequences and genes across species suggest a shared ancestry, while variations in these molecules reflect evolutionary changes over time. Techniques like comparing DNA sequences, analyzing protein structures, and studying gene expression patterns offer insights into evolutionary relationships and processes. The universality of the genetic code itself is strong evidence for a single origin of life and subsequent diversification through evolution.

🧪 Part A: Vocabulary

Match the terms with their definitions:

Answer Key:

• 🔍 1 - C
• 🔬 2 - B
• 🌱 3 - A
• 🌍 4 - D
• 💡 5 - E

📝 Part B: Fill in the Blanks

Fill in the missing words in the following paragraph:

__________ biology provides evidence for evolution by comparing __________ and __________ sequences across different species. The more similar the sequences, the more closely __________ the species are. __________ genes, which perform essential functions, are often highly conserved across diverse organisms.

Answer Key:

• 🔍 Molecular
• 🔬 DNA
• 🌱 protein
• 🌍 related
• 💡 Conserved

🤔 Part C: Critical Thinking

Explain how the universality of the genetic code supports the theory of evolution.

Answer:

• 🧬 The universality of the genetic code – the fact that virtually all known organisms use the same set of codons to translate DNA into proteins – strongly suggests a single common ancestor for all life on Earth.
• 🧪 If different organisms had evolved independently with different genetic codes, we would expect to see significant variations in how genetic information is translated.
• 💡 The shared genetic code indicates that all life forms are related through a process of descent with modification from a universal ancestor that utilized this code.