Question

Select the incorrect statement from the following: (a) Simple organisms like sponges and coelenterates circulate water from their surroundings through their body cavities to facilitate the cells to exchange substances. (b) Different groups of animals have evolved the same method for transport. (c) Blood is the most commonly used body fluid by most of the higher organisms for transport. (d) Lymph also helps in the transport of certain substances in human.

Short answer

The incorrect statement from the given options is (b) Different groups of animals have evolved the same method for transport.

Step-by-step solution

Identifying Statement A

For statement (a), sponges, and coelenterates indeed use water from their surroundings for substance exchange within their body cavities. This is a simple transport mechanism they have evolved and is well-documented in biology. So, statement (a) is correct.

Identifying Statement B

Coming to statement (b), It leads to an incorrect inference. It suggests that different groups of animals have all evolved to use the same transport mechanisms, which is not accurate. Various organisms have evolved distinct methods based on their complexity, environment, and other factors. Hence, statement (b) is incorrect.

Identifying Statement C

In statement (c), it mentions most higher organisms primarily use blood for transport. This is a widely accepted fact in biology. Blood serves as a fundamental medium for transporting nutrients, oxygen, waste products, hormones, and other essential elements within the organism. Thus, statement (c) is correct.

Identifying Statement D

Lastly, for statement (d), indeed, apart from blood, lymph also plays a vital role in the human body for transporting certain substances such as fats, and providing immunity. Therefore, statement (d) is also correct.

Key concepts

Sponges Transport Mechanism

Sponges have a fascinating way of ensuring the exchange of substances like oxygen and nutrients, which is vital for their survival. Unlike more complex organisms, sponges do not have a circulatory system with blood vessels to transport these substances. Instead, they utilize a simple yet effective mechanism based on water flow. Sponges are porous creatures with numerous tiny openings known as ostia. Water from the surrounding environment flows through these openings. As the water moves through their bodies, it passes through specialized cells called choanocytes. These cells help in capturing nutrients and oxygen from the water.

Once the necessary nutrients and dissolved oxygen are extracted, the water is expelled back into the environment through larger openings called oscula. This constant flow enables sponges to meet their biological needs without the necessity of complex structures. It's a brilliant adaptation to their often-sedentary lifestyle in aquatic environments.

The simplicity of this mechanism is uniquely efficient for the sponge's survival, highlighting nature's ability to tailor solutions to organism's specific environments.

Blood as Transport Medium

Higher organisms, including humans, rely heavily on blood as a primary medium for transport within the body. The circulatory system uses blood to transport a variety of essential substances that support life processes. Blood is composed of different components, each serving specific functions.

• Red Blood Cells (RBCs) carry oxygen from the lungs to various body tissues and return carbon dioxide for exhalation.
• White Blood Cells (WBCs) play a crucial role in the immune system, protecting the body against infections.
• Platelets assist in blood clotting, preventing excessive bleeding during injuries.
• Plasma, the liquid component, transports nutrients, hormones, and waste products throughout the body.

With this complex yet efficient system, blood ensures that each cell gets the necessary nutrients while removing waste, thus maintaining the body's internal environment crucial for optimal function. This intricate system of the circulatory network, comprising arteries, veins, and capillaries, facilitates efficient blood flow to all parts of the body.

Lymphatic System Functions

The lymphatic system plays a critical role in maintaining bodily health besides supporting the circulatory system. It is a network consisting of lymphatic vessels, nodes, and a clear fluid called lymph. This system provides several vital functions that are fundamental to the body's homeostasis.

### Function as an Immune System Supporter
Lymph nodes filter harmful substances and pathogens, effectively acting as an immune response primer. They contain lymphocytes, which help in recognizing and attacking unfamiliar substances like bacteria and viruses.

### Transport of Fats
In addition to immunity, the lymphatic system also assists in transporting fats. After the digestion of food, large fat molecules are absorbed through the intestinal villi into the lymphatic vessels. These fats, in the form of chylomicrons, are ultimately released into the bloodstream, ensuring the fats are distributed throughout the body.

### Fluid Balance and Drainage
Another important function of the lymphatic system is maintaining fluid balance. It recovers the excess fluid that escapes from blood vessels into tissues and returns it to the circulatory system, thus preventing swelling and edema.

To sum up, the lymphatic system is a vital component interlinked with the immune and circulatory systems, ensuring the body's fluid environment remains stable while guarding against infections.