NCERT Solutions for Class 11 Biology Chapter 16 – Digestion and Absorption
Are you searching for the best NCERT Solutions for Class 11 Biology Chapter 16 Digestion and Absorption? Look no further than Myclass24, where you will find detailed, accurate, and easy-to-understand answers to every question in this chapter. Digestion and Absorption is one of the most important chapters in Class 11 Biology, especially for students preparing for NEET, where Human Physiology is a major section. The chapter covers the complete human digestive system, the role of various digestive enzymes, the process of absorption of nutrients in the small intestine, and common digestive disorders.
Myclass24 has designed these solutions with a focus on concept clarity so that students from all across India, including those in competitive exam hubs like Kota, Hyderabad, Patna, and Chandigarh, can benefit equally. The answers are framed in exam-ready language and cover all types of questions including short answers, long answers, and diagram-based questions. Getting a strong grip on this chapter will certainly help you secure high marks in both board exams and NEET. Must check the CBSE resources and NCERT Solutions.
NCERT Solutions for Class 11 Biology Chapter 16 PDF – Digestion and Absorption
Download the free PDF of NCERT Solutions for Class 11 Biology Chapter 16 Digestion and Absorption from Myclass24. The PDF covers all NCERT textbook questions with answers, labelled diagrams of the digestive system, and notes on digestive enzymes and absorption mechanisms. It is available for free and is optimised for mobile reading.
Digestion and Absorption – Chapter Overview, Key Facts & Concepts
The human digestive system is a complex system that breaks down food into simpler molecules that can be absorbed into the bloodstream and used by the body. It consists of the alimentary canal and associated digestive glands. The alimentary canal runs from the mouth to the anus and includes the buccal cavity, pharynx, oesophagus, stomach, small intestine, large intestine, rectum, and anus. Check out NCERT Solutions for Class 11 Biology and NCERT Solutions for Class 11 for the rest of the chapters.
Digestion begins in the mouth, where salivary amylase (ptyalin) starts the breakdown of starch into maltose. The food then travels through the oesophagus via peristalsis to the stomach, where the gastric glands secrete gastric juice containing pepsinogen, HCl, and intrinsic factor. HCl activates pepsinogen to pepsin, which digests proteins into proteoses and peptones. The acidic environment also kills most microorganisms ingested with food.
The small intestine is the primary site of digestion and absorption. It is divided into duodenum, jejunum, and ileum. The liver secretes bile, which emulsifies fats. The pancreas secretes pancreatic juice containing trypsinogen, chymotrypsinogen, amylase, lipase, and nucleases. The intestinal mucosa secretes enzymes like maltase, sucrase, lactase, and peptidases.
Absorption of nutrients occurs mainly in the small intestine. The inner wall of the small intestine is lined with finger-like projections called villi and microvilli (collectively called the brush border), which enormously increase the surface area for absorption. Glucose and amino acids are absorbed by active transport, fatty acids and glycerol are absorbed into lacteals, and water is absorbed by osmosis.
Key Digestive Enzymes and Their Functions
| Enzyme | Source | Substrate | Product |
| Salivary Amylase | Salivary glands | Starch | Maltose |
| Pepsin | Stomach (chief cells) | Proteins | Peptides |
| Trypsin | Pancreas | Proteins/peptides | Dipeptides |
| Lipase | Pancreas | Fats/triglycerides | Fatty acids + glycerol |
| Maltase | Intestinal glands | Maltose | Glucose |
| Nucleases | Pancreas | Nucleic acids | Nucleotides |
Common Digestive Disorders
| Disorder | Description |
| Jaundice | Liver disorder; yellowing of skin due to excess bilirubin |
| Vomiting | Reflex expulsion of stomach contents through the mouth |
| Diarrhoea | Frequent watery stools due to intestinal infection or irritation |
| Constipation | Irregular bowel movement; faeces retained in rectum |
| Indigestion | Incomplete digestion; pain and fullness in abdomen |
The large intestine absorbs water and electrolytes from undigested material, forming semi-solid faeces. It also absorbs vitamin K produced by gut bacteria. The rectum stores faeces until defecation. An important fact for NEET aspirants: the total length of the small intestine in humans is about 6–7 metres, while the large intestine is about 1.5 metres long.
Hepatic portal vein carries absorbed nutrients from the small intestine to the liver for processing. The liver plays a central role in metabolism, detoxification, and regulation of blood glucose levels. Understanding this chapter thoroughly, including the structure of teeth, the role of the epiglottis in preventing food from entering the trachea, and the neural and hormonal control of secretion, is essential for scoring well in exams.
FAQs for NCERT Solutions for Class 11 Biology Chapter 16 Digestion and Absorption
NCERT Solutions for Digestion and Absorption explain the human digestive system and the processes involved in food digestion and nutrient absorption. The chapter covers the alimentary canal, digestive glands, digestive enzymes, digestion of carbohydrates, proteins, and fats, and nutrient absorption mechanisms. These solutions provide detailed explanations and textbook answers that simplify physiological concepts. Students learn how the body converts food into usable nutrients. The chapter is important for examinations because it forms the foundation for understanding human nutrition and metabolism. Regular revision improves conceptual clarity and exam performance.
Digestion is essential because it breaks down complex food substances into simpler molecules that can be absorbed and utilized by the body. NCERT solutions explain the roles of saliva, stomach acids, pancreatic enzymes, and intestinal secretions in digestion. Students understand how nutrients are processed and absorbed to support growth, energy production, and maintenance. Detailed explanations help learners connect digestive functions with overall health. Understanding digestion is important for answering physiology-based questions in school and competitive examinations.
Nutrient absorption occurs mainly in the small intestine through specialized structures called villi. NCERT solutions explain the absorption of carbohydrates, proteins, fats, vitamins, minerals, and water in a simple and organized manner. Students learn the importance of intestinal adaptations and transport mechanisms. These explanations help improve understanding of human physiology and strengthen preparation for examinations. Consistent practice ensures better retention of important concepts.
Students should focus on digestive organs, digestive enzymes, digestion of food components, absorption mechanisms, and disorders of the digestive system. NCERT solutions provide detailed explanations and exam-oriented answers for these topics. Thorough preparation helps students answer conceptual and application-based questions confidently. These concepts are frequently tested in school examinations and entrance tests.