Since there isn't much prey during winter, the bears have to eat a lot of the remaining prey and then go into sleeping, so that they will not go through the whole winter without food.
Organs of excretion make up the excretory system. They include the kidneys, large intestine, liver,and lungs. The kidneys filter blood and form urine. They are part of the urinary system, which also includes the ureters, bladder, and urethra.
Answer:
1. B. Methane
2. C. Methane collection system
