The following questions refer to the digestive system structures in Figure 41.1.

Figure 41.1
-Adult lampreys attach onto large fish and feed regularly on their body fluids. Given this continuous supply of food, which one of the following is most likely missing in lampreys?

Question

The following questions refer to the digestive system structures in Figure 41.1.
  
Figure 41.1
-Adult lampreys attach onto large fish and feed regularly on their body fluids. Given this continuous supply of food, which one of the following is most likely missing in lampreys?

Quizplus · Accepted Answer

Lampreys are agnathan fishes that lack jaws and a true stomach. Instead, they have a circular, muscular oral disc used for attaching to the host and rasping at tissues with keratinized teeth, and a long intestine that is adapted for absorption of nutrients from body fluids. Lampreys also lack a liver, pancreas, and gallbladder, which are accessory digestive organs found in jawed vertebrates. These organs help with digestion, absorption, and storage of nutrients, but are not essential for survival in lampreys.

The Following Questions Refer to the Digestive System Structures in Figure