Question

Which of the following is true of the digestive tracts of minnows? a. They are incomplete but have both a mouth and an anus. b. They are complete, facilitating compartmentalization of digestion in different organs. c. They are incomplete, with no accessory organs. d. They are complete and include a large gastrovascular cavity.

Short answer

The correct answer is (b) They are complete, facilitating compartmentalization of digestion in different organs.

Step-by-step solution

Understand Complete and Incomplete Digestive Tracts

A complete digestive tract is also called an alimentary canal. It consists of a continuous tube running through the body from mouth to anus, where food enters the mouth and waste is eliminated through the anus. In contrast, an incomplete digestive tract has only one opening, which serves as both the mouth and the anus. Examples of animals with an incomplete digestive tract include jellyfish and flatworms.

Characteristics of Minnows

Minnows are small freshwater fish species belonging to the family Cyprinidae. They are vertebrates, shares common characteristics with other fish, including a digestive system with an alimentary canal.

Compare Options with Minnow's Digestive Tract Characteristics

Using the knowledge of minnows' digestive tract characteristics, compare each option to determine which is true of minnows' digestive tracts: a. Incomplete but have both a mouth and an anus: This is incorrect because minnows have a complete digestive tract. b. Complete, facilitating compartmentalization of digestion in different organs: This is correct, as minnows have a complete digestive tract with different organs where the process of digestion occurs. c. Incomplete, with no accessory organs: This is incorrect because minnows have a complete digestive tract with accessory organs. d. Complete and include a large gastrovascular cavity: This is incorrect because minnows have an alimentary canal, and gastrovascular cavities are found in animals with incomplete digestive tracts.

Choose the Correct Answer

Based on the comparison in step 3, the correct answer is: b. They are complete, facilitating compartmentalization of digestion in different organs.

Key concepts

Alimentary Canal

The alimentary canal is a fundamental aspect of the vertebrate digestive system, forming a continuous tube running from the mouth to the anus. This path allows for an efficient process where food is taken in, nutrients are absorbed, and waste is expelled.

Key features of the alimentary canal include its segmentation into specialized regions that perform distinct functions. For example, the esophagus moves food to the stomach, the stomach breaks down food chemically with acids, and the small intestine is the primary site of nutrient absorption.

The alimentary canal not only simplifies the process of digestion and absorption but also provides a barrier against pathogens. Its structure supports digestive efficiencies, like sequential processing where food components are broken down in a stepwise fashion.

Vertebrate Digestive System

The vertebrate digestive system is a complex and highly coordinated network of organs. It includes the alimentary canal and accessory organs such as the liver, pancreas, and gallbladder. In vertebrates, including humans and minnows, digestion is a compartmentalized process.

Each organ within the system contributes to the overall digestive process. For instance, the liver produces bile that aids in fat digestion, the pancreas produces enzymes to further break down food, and the gallbladder stores bile.

These specialized structures exemplify the evolutionary advancements that enable vertebrates to utilize a wide range of food sources. They also enhance digestive efficiency and nutrient absorption, facilitating a high energy intake which supports complex bodily functions.

Minnows Biology

Understanding minnows biology, particularly their digestive system, unveils their adaptation to life in freshwater environments. Minnows, small fish within the family Cyprinidae, possess a complete digestive tract characteristic of vertebrates.

This inclusion allows for the organization of the digestive process across multiple organs, supporting a diet that includes plants, insects, and detritus. Remarkably, although small in size, minnows have adapted to efficiently process their food, ensuring they absorb the necessary nutrients needed for growth and reproduction.

The study of minnows provides insight into vertebrate evolutionary biology and helps in understanding how even small species are equipped with complex organ systems to thrive in diverse ecosystems.