Exercise 3. Answer the following questions: 1. What are the functions of the skeletal and muscular systems? 2. What is carried by the blood stream? 3. What is the chief function of the blood? 4. What does the nervous system consist of? 5. What is the main function of the respiratory system? 6. What does the urinary system consist of? 7. How do the kidneys produce urine? 8. How is the urine discharged from the body?

The main function of the skeletal system is structural. The main function of the muscular system is to move us about.

The nutrients, oxygen, special substances which are required by cells are carried by the blood stream, and the cellular wastes, and sometimes other materials produced by the cells are carried away by the blood stream.

Its function is mainly that of transportation system.

The nervous system consists of the brain and spinal cord, nerves, ganglia and receptors.

Its main function is to convey oxygen to the lungs, where it can enter the blood stream and to remove carbon dioxide, which escapes from the blood into the lung spaces.

The urinary system consists of the kidneys, which produce urine by removing nitrogenous and other wastes from the blood, the two ureters, which convey the urine away from the kidneys, the urinary bladder where the urine is stored until it is discharged and the urethra through which the urine is discharged.

The kidneys produce urine by removing nitrogenous and other wastes from the blood.

The urine is discharged from the body through the urethra.