Plants have to store up their extra food for when they need the energy, such as in times of drought when the plant might not be able to be fed as consistently. Most often, this part of the plant is located within the root system underground. Some animals have learned to tear the plants out of the ground and eat the roots when they need the extra nutrition and water.
Organ
As in ANY living animal, its brain, then heart and lungs or gills.
Any animal that breathes has a respiratory organ
What you see when you talk about carrots is the taproot.
It depends on the organ, animal species, and disease, but generally, with the diseased organ.
Lungs
Urinary bladder
Most people call this an organ system.
No, the rectum is the lower part of the large intestine between the colon and the anal canal. The storage organ for urine is the urinary bladder.
The main organ for starch storage in plants is the potato tuber, though starch is also stored in other parts like seeds and roots. In animals, glycogen serves a similar function as a storage form of carbohydrates, primarily found in the liver and muscles, but starch itself is not stored in animal tissues.
The bladder stores the urine.
skeletal