Question

answer bank un digested bacteria evolved into mitochondria. divergence of early eukaryotes occurred. host cell ingested cyanobacteria. host cell ingested aerobic bacteria. undigested bacteria evolved into chloroplasts.

Explanation:

This diagram illustrates the endosymbiotic theory, which explains the origin of eukaryotic organelles like mitochondria and chloroplasts. We map the answer bank items to the steps in order of the evolutionary process:

1. The first step is a host cell ingesting an aerobic bacterium, which becomes the ancestor of mitochondria.
2. The undigested aerobic bacterium evolves into mitochondria.
3. A divergence of early eukaryotes occurs, leading to two lineages.
4. One lineage's host cell ingests cyanobacteria, the ancestor of chloroplasts.
5. The undigested cyanobacteria evolve into chloroplasts.
6. The final step is the divergence of early eukaryotes leading to distinct eukaryotic groups.

Answer:

• Bottom left box (first step): Host cell ingested aerobic bacteria.
• Box connected to the cell with mitochondria: Undigested bacteria evolved into mitochondria.
• Middle right box: Divergence of early eukaryotes occurred.
• Box connected to the cell with both mitochondria and chloroplast (upper path): Host cell ingested cyanobacteria.
• Top right box: Undigested bacteria evolved into chloroplasts.
• Bottom right box: Divergence of early eukaryotes occurred.