Assistant Laboratory Animal Technician (ALAT) Practice Exam

Which of the following is true about the anatomy of rodents?

1. They have continuously growing incisors

2. Their molar teeth are also front-facing

3. They lack a cecum

4. They have a complex stomach structure

The correct answer is: They have continuously growing incisors

Rodents are indeed characterized by their continuously growing incisors. This anatomical feature is essential for their survival because their teeth need to be constantly worn down through the gnawing and chewing of various materials, such as wood, seeds, and other vegetation. If the incisors grow too long, they can cause significant health issues, including difficulty eating and injuries to the mouth. This continuous growth is a result of the specific structure of their dental enamel and the arrangement of their teeth, which allows them to maintain a functional bite as they wear their incisors down naturally through their typical behaviors. This distinct trait sets rodents apart from many other mammals, which have a set number of teeth that do not continue to grow after reaching maturity. In contrast, the other options describe different anatomical features that don't apply to rodents. Their molar teeth are not front-facing but are situated further back in the mouth for grinding down food. Additionally, rodents possess a cecum, which plays a role in the fermentation of plant material, and their stomach structure is generally simple rather than complex, with a single-chambered system.