Science · Class 7
Nutrition in Animals
Human digestive system, nutrition in amoeba, and food pipe to absorption.
4 sections15–25 min read6 MCQs · 2 examples
Chapter Overview
Animals are heterotrophs. This chapter covers types of nutrition, human digestive system, digestion in grass-eating animals (rumination), and feeding in Amoeba.
Human Digestive System
- Mouth → oesophagus → stomach → small intestine → large intestine
- Salivary glands, liver, pancreas add digestive juices
- Small intestine: absorption through villi
- Large intestine: water absorption; rectum stores faeces
Digestion in Other Animals
- Ruminants (cow): rumen bacteria digest cellulose; regurgitate cud
- Amoeba: pseudopodia engulf food; food vacuole digests
- Different teeth: incisors, canines, premolars, molars
Components of Digestive Juices
- Saliva: amylase breaks starch
- Gastric juice: pepsin + HCl in stomach
- Bile emulsifies fats; pancreatic juice digests proteins, fats, carbs
Solved Examples
Step-by-step solutions — read each step before checking the final answer.
Digestion path
In which part is food mainly absorbed?
- 1Most absorption in small intestine
- 2Inner wall has finger-like villi
- 3Large surface area for nutrients
Answer
Small intestine
Ruminant digestion
Why do cows chew cud?
- 1Grass has cellulose hard to digest
- 2Partially digested food returned to mouth
- 3Chewed again for better breakdown
Answer
Rumination aids cellulose digestion
Key Points to Remember
- ✓ Bile is stored in gall bladder
- ✓ Villi increase absorption surface
- ✓ Assimilation: absorbed food used by body cells
Exam Tips
- • Draw human digestive system with labels
- • Distinguish ingestion, digestion, absorption, egestion
- • Explain ruminant digestion
Practice MCQs — Nutrition in Animals
Test your understanding with topic-wise multiple choice questions. Explanations appear after each answer.
Question 1 of 6Score: 0/0
Main site of absorption is: