Which of the following statements is true? Blood in the heart only flows one-way.
The heart is the largest organ in the body.
The ventricles receive blood from the body.
The atria pump oxygen-rich blood to the body.

Answer is D

Explanation:

As the heart pumps blood, a series of valves open and close tightly. These valves ensure that blood flows in only one direction, preventing backflow. The tricuspid valve is situated between the right atrium and right ventricle. The pulmonary valve is between the right ventricle and the pulmonary artery.

answer: 20 percent

the fish culture has become a developing commercial practice in developing countries which is already prominent in developed countries of the world. the major fish protein demand is being supplemented in developing countries is   fishing to meet the needs of the growing population. therefore, in some developing nations, the percentage of animal protein from fish in the diet can be as high as 20 percent.

the answer is d. embryo