Nutrition in Other Animals
Class 7 Science · Chapter 9: Life Processes in Animals · NCERT Curiosity section 9.1.2
Learn
Animals eat in many ways: bees and sunbirds sip nectar, babies drink milk, a python swallows prey whole, and some water animals filter tiny food from the water around them. On a farm visit, Zoya sees a cow lying down, chewing steadily though it is not grazing. "What is it eating?" she asks.
Cows, buffaloes and goats quickly swallow half-chewed grass into a large stomach chamber (the rumen), where it is partly digested. Later, the food is brought back to the mouth and chewed again slowly: rumination. Such animals are ruminants; a cow can spend about 8 hours a day chewing!
Birds have no teeth. Instead they have a muscular chamber, the gizzard, which grinds food, often with the help of small stones (grit) the bird swallows. Different animals have alimentary canals shaped to suit the foods they eat.
Remember
- Ruminants like cows partly digest grass in the rumen, then bring it back to chew again.
- Birds grind food in a gizzard with grit; alimentary canals vary with diet.
Quick check
Why does a cow keep chewing even when it is not grazing?
- it brings back partly digested food to chew again (rumination)
- it is chewing air
- its teeth itch
- it is breathing
Answer
it brings back partly digested food to chew again (rumination). Ruminants chew their food twice.
Think about it
Why might a grass-eater need a longer, more complex gut than a meat-eater?
One answer
Grass is tough and full of fibre that is hard to break down, so it needs more time, more chewing and help from gut bacteria.
Practice
Practise with fresh questions at three levels (easy, medium, hard), some answered hands-on, with hints and worked answers. Get 4 of your last 5 right to finish the topic.