Problem 195 - Objective Biology for NEET

Question

Which of the following tract open into a common chamber cloaca in amphibians? (a) Alimentary canal (b) Urinary tract (c) Reproductive tract (d) All of these

Step-by-Step Solution

Answer

The correct answer is (d) All of these. The alimentary canal, urinary tract, and reproductive tract all open into the common chamber, cloaca in amphibians.

Step 1: Understanding the Concept of Cloaca in Amphibians

Cloaca is a common chamber and outlet into which the intestinal, urinary, and genital tracts open in amphibians. It acts as the body's exit point for both the urinary and digestive systems.

Step 2: Evaluating the Options

Look at each of the provided options. Alimentary canal pertains to the digestive system, urinary tract refers to the urinary system, and reproductive tract relates to the genital system. All of these systems in amphibians end in the cloaca.

Step 3: Select the Correct Answer

Since all the mentioned tracts - the alimentary canal, the urinary tract, and the reproductive tract - open into the cloaca in amphibians, the correct answer is (d) All of these.

Key Concepts

Alimentary Canal

The alimentary canal is a key component of an amphibian's digestive system. It is a long tube that runs from the mouth to the cloaca.
This passage allows food to be efficiently broken down and absorbed. The journey of food begins in the mouth, where enzymes start digesting it as it gets chewed.
Then, the food travels down the esophagus into the stomach. Here, gastric acids and enzymes continue to break down the food into smaller pieces.

• In the stomach, digestion becomes more intensive, with the help of movements that mix gastric juices with the ingested food.
• After the stomach, the food moves into the small intestine, where most nutrients are absorbed into the bloodstream.
• The remaining waste then passes through the large intestine, where water is absorbed, leaving solid waste ready for excretion.

Ultimately, the alimentary canal guides waste to the cloaca, where it can exit the body. This system is crucial for maintaining the energy and nutrient supply in amphibians.

Urinary Tract

Amphibians have an intriguing urinary tract system that plays a vital role in maintaining fluid balance and removing waste.
The urinary tract includes structures such as the kidneys, ureters, and the bladder. Each part has its unique function:

• The kidneys filter blood by removing waste products and excess substances, creating urine.


• The ureters are tubes that carry this urine from the kidneys to the bladder, where it is stored temporarily.


• From the bladder, urine moves into a common cavity known as the cloaca. This chamber then expels urine from the body.

This seamless system helps amphibians efficiently manage waste and regulate their internal environment. It ensures an amphibian maintains the right levels of salts, water, and other essential substances.

Reproductive Tract

The reproductive tract in amphibians is essential for their reproduction and the continuation of their species.
This system includes organs responsible for producing and transporting gametes (sperm and eggs).

• In males, the reproductive tract consists of testes, which produce sperm.


• The sperm travel through ducts to reach the cloaca, where they can be released during mating.


• In females, ovaries produce eggs, which also move through structured ducts to the cloaca.

The cloaca plays a crucial role as it is a shared exit point for reproductive cells, facilitating mating and fertilization processes.
Amphibians employ this efficient system to ensure their reproductive success in their aquatic or terrestrial environments.