Correct Answer: D) buoyancy

Explanation

Fish have a special organ called the swim-bladder, which is a gas-filled sac located in their abdomen. One of the major functions of the swim-bladder is to help the fish control its buoyancy in water. Buoyancy is the upward force exerted by water that helps the fish stay afloat and move up or down in the water column. When the fish wants to rise in the water, it inflates its swim-bladder with gas, which makes it less dense than water, allowing it to float upwards. Conversely, when the fish wants to sink, it deflates its swim-bladder, which makes it denser than water, causing it to sink. Therefore, the correct option for the major function of swim-bladder in fish is D: buoyancy. Swim-bladders help fish regulate their buoyancy and maintain their position in the water column. Option A (breathing), B (swimming), C (diving), are not the correct option Understanding the role of swim-bladders in fish is essential for understanding the adaptations that help fish survive in aquatic environments.

Correct Answer: A. Indiscriminate poaching

Correct Answer: D. XXand XY

Correct Answer: A. tendons

Correct Answer: D. Fern on palm tree

Correct Answer: C) ganglia

Explanation

In Biology, the nervous system is responsible for communication between different parts of the body. The nervous system comprises of many different types of cells, but the most important of these cells are the neurons. The neurons are the cells responsible for transmitting signals between different parts of the body. The question is asking about small masses of nervous tissue in which many neurons have their nuclei. These small masses of nervous tissue are referred to as ganglia. Ganglia are found outside the brain and spinal cord and contain many cell bodies of neurons. They are responsible for processing and relaying information to and from the peripheral nervous system. Dorsal roots and ventral roots are two types of nerves that extend from the spinal cord. They are responsible for carrying sensory and motor signals respectively. Synapses, on the other hand, are junctions between two neurons where signals are transmitted from one neuron to another. Therefore, the correct answer to this question is option C: ganglia. Ganglia are small masses of nervous tissue that contain many neuron cell bodies and are responsible for processing and relaying information to and from the peripheral nervous system.

Correct Answer: D. mitrochondria and chloroplast

Correct Answer: D. Survival of the fittest

Correct Answer: A. acetylcholine

Correct Answer: A. animal rather than plant remains