Based on the tree of life in Figure 16.12, would you expect human proteins to be more similar to fungal proteins or to plant proteins? Would you expect plant proteins to be more similar to fungal proteins or to human proteins?

Key Concepts

Phylogenetic Tree

A phylogenetic tree is a diagram that represents evolutionary relationships among various biological species based on similarities and differences in their genetic characteristics. It illustrates how species are related through common ancestry, allowing for predictions about the genetic similarities between organisms. Understanding the tree of life helps in determining which organisms share more closely related proteins.

Protein Similarity

Protein similarity refers to the degree to which proteins from different organisms share structural and functional characteristics. This similarity can be assessed through sequence alignment and comparison of amino acid sequences. Proteins that are more similar often perform similar functions and are derived from closely related species, making this concept crucial for understanding evolutionary relationships.

Common Ancestry

Common ancestry is the concept that different species share a common ancestor from which they have evolved over time. This principle is fundamental in evolutionary biology and helps explain the genetic and protein similarities observed among species. By recognizing common ancestry, one can infer that humans, fungi, and plants may have varying degrees of protein similarity based on their evolutionary paths.