Chewing the cud
Rumination.
A cow chewing
A cow sits and chews, even when it has no grass in its mouth.
Why does a cow chew again?
What this lesson covers
The idea
Grass-eating animals partially chew and swallow grass, partly digest it in the stomach, then bring it back to the mouth for gradual chewing; this is rumination, and such animals are ruminants.
A cow chewing
A cow sits and chews, even when it has no grass in its mouth.
Why does a cow chew again?
- It brings partly digested food back to chew it more
- It is tasting the air
- It forgot to swallow
Follow the grass
Press Next step four times. Follow the grass round the circle.
Chew it twice
The cow chewed the grass a little, swallowed it, and the stomach partly digested it. Then the food came back to the mouth and the cow chewed it slowly. A cow spends about 8 hours a day just chewing.
Grass-eating animals partially chew and swallow grass, partly digest it in the stomach, then bring it back to the mouth for gradual chewing. This is rumination, and such animals are ruminants.
Notes
Grass-eating animals partially chew and swallow grass, partly digest it in the stomach, then bring it back to the mouth for gradual chewing. This is rumination, and such animals are ruminants.
Check yourself
What is rumination?
Grass-eating animals that ruminate are called …
Which of these is a ruminant?
About how many hours a day does a cow spend chewing its food?
Answer: 8 h
A cow spends about 8 hours a day just chewing the food.
- Chewing food only once. In rumination the food is chewed again after partial digestion.
- Bringing partly digested food back to the mouth to chew it again — correct. Yes!
- Swallowing without any chewing. A ruminant first chews the grass a little, and chews it again later.
- carnivores. Carnivores eat flesh. Grass-eating animals that ruminate are called ruminants.
- predators. Predators hunt other animals. Grass-eating animals that ruminate are called ruminants.
- ruminants — correct. Yes!
- Cow — correct. Yes!
- Python. A python swallows the animals it preys upon. It is not a grass-eating ruminant.
- Human. Humans do not bring food back from the stomach to chew it again.