The 15th day of the first lunar month is a traditional festival in China-Lantern Festival. Lantern Festival has the custom of eating Yuanxiao, which is made of glutinous rice.

(1) Rice belongs to monocotyledonous plants, and the nutrients of monocotyledonous plants mainly exist in the endosperm of seeds, so glutinous rice is rich in nutrients such as sugar and protein, which are mainly stored in the endosperm of rice seeds.

(2) Fat is digested in the small intestine, and the digestive juice for digesting fat includes bile secreted by the liver, intestinal juice secreted by intestinal glands and pancreatic juice secreted by the pancreas.

(3) The small intestine is the main site for digestion and absorption, and protein is an essential component of cells. In the digestive tract, protein is finally digested into amino acids, which can be absorbed by villi of small intestine and enter the blood of villi capillaries.

(4) Rough skin and night blindness are caused by lack of vitamin A. Animals' livers are rich in vitamin A, and corn and carrots contain carotene, which can be converted into vitamin A in the body. Eating more can prevent night blindness and rough skin.

So the answer is: (1) endosperm.

(2) Liver, intestinal glands and pancreas

(3) Capillaries

(4) vitamin a