Which of the following experimental model organisms are used to study invertebrates? Escherichia coli Saccharomyces cerevisiae Mus musculus, Rattus norvegicus Gallus gallus, Arabidopsis thaliana Drosophila melanogaster, Caenorhabditis elegans

The experimental model organisms used to study invertebrates are Drosophila melanogaster and Caenorhabditis elegans.

Here's why:

1. Escherichia coli: This is a bacterium, not an invertebrate. It's often used in studies related to microbiology and genetics.

2. Saccharomyces cerevisiae: This is a species of yeast, a type of fungus. It's not an invertebrate, but it's commonly used in molecular and cell biology studies.

3. Mus musculus, Rattus norvegicus: These are the scientific names for the house mouse and the brown rat, respectively. Both are vertebrates, not invertebrates.

4. Gallus gallus, Arabidopsis thaliana: Gallus gallus is the red junglefowl, the wild ancestor of the domestic chicken. Arabidopsis thaliana is a small flowering plant. Neither of these are invertebrates.

5. Drosophila melanogaster, Caenorhabditis elegans: These are the fruit fly and a type of roundworm, respectively. Both are invertebrates and are widely used in biological research. Drosophila melanogaster is often used in genetics and developmental biology studies, while Caenorhabditis elegans is commonly used in neurobiology and developmental biology studies.