Food then moves on to the jejunum. This is the most nutrient absorptive section of the small intestine. The liver regulates the level of nutrients absorbed into the blood system from the small intestine. From the jejunum, whatever food that has not been absorbed is sent to the ileum which connects to the large intestine. The first part of the large intestine is the cecum and the second portion is the colon. The large intestine reabsorbs water and forms fecal matter.