Video Transcript
Amer and Dalia are talking about
what role the mouth plays in digestion. Amer says, “The mouth secretes
saliva that contains digestive enzymes.” Dalia says, “The mouth breaks down
food by cutting, tearing, and grinding through the work of teeth.” Which student is correct?
We know that the mouth plays a
number of different roles in digestion. Salivary glands are found in the
mouth. And they excrete a liquid called
saliva. Saliva is an important part of
digestion because the saliva contains enzymes which break down food, like starch,
into simpler substances, like sugar. So we can see that Amer is correct;
the mouth does secrete saliva.
Let’s think about what Dalia
says. The mouth breaks down food by
cutting, tearing, and grinding through the work of teeth. Teeth are an important part of the
role of the mouth in digestion. So Dalia is also correct. Since both of the statements are
true, we can give the answer that both students are correct.
Before we finish with thinking
about the role of the mouth in digestion, there is one other part of the mouth which
also helps food on its digestive journey: the tongue. We might not have thought that our
tongue helps us digest our food. It’s great for tasting our food,
but how does it help digest it?
Well, firstly, the tongue helps
push the food around our mouth. That then allows our teeth to tear
and grind the food into smaller pieces. The tongue also helps mix our food
with saliva, which allows all the digestive enzymes to start mixing and working. Finally, our tongues help with
swallowing our food.
