KERALA PSC / CDPO / BIOLOGY / HUMAN BODY / DIGESTIVE SYSTEM / NOTES / OBJECTIVE QUESTIONS / STUDY MATERIALS / GENERAL KNOWLEDGE / KERALA PSC PRELIMINARY

 

KERALA PSC / CDPO / BIOLOGY / HUMAN BODY / DIGESTIVE SYSTEM / NOTES / OBJECTIVE QUESTIONS / STUDY MATERIALS / GENERAL KNOWLEDGE / KERALA PSC PRELIMINARY

KERALA PSC / CDPO / BIOLOGY / HUMAN BODY / DIGESTIVE SYSTEM / NOTES / OBJECTIVE QUESTIONS / STUDY MATERIALS / GENERAL KNOWLEDGE / KERALA PSC PRELIMINARY

·      The process of converting food into energy giving substances is carried out by the digestive system.

·      The digestive system consists of the alimentary canal (buccal cavity, oesophagus, stomach, small intestine, large intestine ending in the rectum and anus) and the associated glands.

·      Alimentary canal is a long tube which is 6-9 meters long and starts from mouth and ends at anus.

·      The parts of the alimentary canal are Mouth, Pharynx, Oesophagus, Stomach, Small intestine, Large intestine.

·      The mouth leads into a funnel shaped pharynx, which is the common passage for food and air.

·      Pharynx lead into oesophagus which is about 25cm long.

·      The three divisions of large intestine are Caecum, Colon and Rectum.

·      Small intestine: It is the largest and narrow tubular part of alimentary canal. It measures about 6 meters in length.

·      Small intestine, the highly coiled portion has 3 divisions such as duodenum, jejunum and ileum.

·      Digestion is of two types:

Ø Intra Cellular digestion: The digested products pass to the cytoplasm across the endocytotic inside membrane. Eg: Amoeba

Ø Extra Cellular Digestion: Cell synthesizes one or more enzymes for digesting specific type of nutrient.

·      The liver is the largest gland of the body. It secretes bile, containing bile pigments and bile organic salt. If intestine contains no food, the bile flows to gall bladder, instead of duodenum; which contract and secrete bile later when food is present in intestine.

·      The large intestine secretes no enzyme and play only a minor role in the absorption of nutrients.

KERALA PSC / CDPO / BIOLOGY / HUMAN BODY / DIGESTIVE SYSTEM / NOTES / OBJECTIVE QUESTIONS / STUDY MATERIALS / GENERAL KNOWLEDGE / KERALA PSC PRELIMINARY