Wednesday, 13 February 2013

2.26 describe the structures of the human alimentary canal and describe the functions of the mouth, oesophagus, stomach, small intestine, large intestine and pancreas

The mouth
Mechanical digestion happens here- your jaw action.
A bolus is created; this is a ball of food covered in saliva. This is help full as the food is lubricated to enable swallowing and enzymes in the saliva can begin to break down the food. (amylase)

The oesophagus
this tube connects you mouth and stomach. It is next to the trachea which is covered by the epiglottis when you swallow so the food only enters the oesophagus.
Peristalsis- or muscular contractions- moves the food downward.

The stomach
Churning mechanically digests whilst enzymes do so chemically.
Chyme is the name for liquid food existing in the stomach.

The small intestine
This absorbs digested molecules into the blood stream.
Villi cover the inside giving it a large surface area which many molecules can diffuse through into the blood.

Large intestine
This absorbs water from undigested food, producing faeces.

This produces the enzymes lipase, amylase and protease.


  1. Pancreas should be just before small intestine.

    Thanks for all the help!

    1. This was me revising for end of year exams last year. It's really weird seeing myself.

      Anyway, you got me an A* back then so let's do it again for the real thing :D

    2. Oh mate nice! Best of luck :))

    3. Thanks for all the help from your side, its people like you who keep the blog going even when I have no recolection of GCSE haha. Remeber not to work too hard will!

    4. Now you're probably studying for your A-level exam. I'm only revising for my year 10 IGCSE exams.

  2. It's important to mention that gastric juice in the stomach contains: 1) protease to digest protein and 2) hydrochloric acid which maintains the pH and also kills bacteria.

  3. Stomach contains acid which helps digest food and small intestine seceretes enzymes to help digest food as well

  4. this has helped me so much ! thank you xx

  5. I got DE in my IGCSE science double award... I really want to cry when I got my result. I've study so hard and yet...

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