Download NAME: DATE: THE HUMAN DIGESTIVE SYSTEM The digestive

NAME: ___________________________ DATE: ___________________________
THE HUMAN DIGESTIVE SYSTEM
The digestive system - (also called the __________________________________ or GI tract) is
a series of organs and glands that processes food and breaks the ______________ molecules of
food into ________________ molecules.
Our body has to break food down into smaller molecules and get rid of waste.
The Digestive Process:
The start of the process
 The digestive process begins in the _____________________.
 Food is partly broken down by the process of ______________ and by the chemical
action of _________________ ________________ (physical and chemical digestion).
 After being chewed and swallowed, the food enters the _______________________.
 The esophagus is __________ ___________ that runs from the mouth to the stomach.
Like all parts of the tube, it uses wave-like ___________________ movements (called
__________________) to force food from the throat into the stomach.
(This is why astronauts can swallow food where this no gravity!)
 The _____________________ is a large, sack-like organ that ____________________
and bathes it in a very strong _____________ (means stomach) ________ (Hydrochloric
acid HCl).
 There are also some ________________ _______________ in the stomach.
 Food in the stomach that is partly digested and mixed with stomach acids is called
________________________.
 After being in the stomach, food enters the ____________ _____________________.
 In the small intestine, ____________ (squirted from the liver and gall bladder), and
_________________ ______________ (squirted from the pancreas), and other
_________________ ______________ (produced by the small intestine itself) cause the
_______________ breakdown of food.
 After passing through the small intestine, food passes into ________________
_____________________.
 In the large intestine: ___________ and ___________________ (chemicals like sodium)
are removed from the food. Many _____________ (such as bacteria like Escherichia coil
or E. coli for short) in the large intestine _____________ in the digestion process.
 ______________ ____________ is then stored in the _____________ until it is excreted
via the _____________.
Mixed Bag of Terminology
- the passage through which food passes, including the
mouth, esophagus, stomach, intestines, and anus.
________________ - the first part of the digestive system, where food enters the body. Chewing and
salivary enzymes in the mouth are the beginning of the digestive process (breaking down the food).
___________________________ - the long tube between the mouth and the stomach. It uses
rhythmic muscle movements (called peristalsis) to force food from the throat into the stomach.
__________________ - a sack-like, muscular organ that is attached to the esophagus. Mostly
chemical and a little bit of mechanical digestion takes place in the stomach. When food enters the
stomach, it is churned in a bath of acids and enzymes.
The
Intestine: “__________________ “digestion
1. ____________________ - the first part of the small intestine; it is C-shaped and runs from the
stomach to the jejunum.
2. ____________________ - the long, coiled mid-section of the small intestine; it is between the
duodenum and the ileum. Most of the chemical digestion occurs here.
3. ____________________ - the last part of the small intestine before the large intestine begins.
The
Intestine: “ ____________ ________________”
1. ___________ - the first part of the large intestine; the appendix is connected to the caecum.
2. _______________ - a small sac located on the caecum. No current function. Is vestigial (used to
be for digesting cellulose – like how a cow's stomach can, and how some monkey-like animals can.
3. ________________________ colon - the part of the large intestine that run upwards; it is located
after the caecum.
4. ________________________ colon - the part of the large intestine that runs horizontally across
the abdomen.
5. ________________________ colon - the part of the large intestine that run downwards after the
transverse colon and before the sigmoid colon.
6. _________________________ colon - the part of the large intestine between the descending
colon and the rectum.
7._________________________ - the lower part of the large intestine, where feces are stored before
they are excreted.
8. ____________ - the opening at the end of the digestive system from which feces (waste) exits the
body.
Accessory Organs of Digestion
(not part of the alimentary canal (tube) – but produce chemicals that get squirted into the tube)
1. ______________- a large organ located above and in front of the stomach. It filters toxins from the
blood, produces some vitamins and makes bile (which breaks down fats) and some blood proteins
2. _____________________________ - a small, sac-like organ located in the liver. It stores and
releases bile (a digestive chemical which is produced in the liver) into the small intestine.
_____________ - a digestive chemical that is produced in the liver, stored in the gall bladder, and
secreted into the small intestine. Bile emulsifies (makes smaller) large fat gobs into little goblets that
can be more easily digested.
3. ______________________ - an enzyme-producing gland located below the stomach and above
the intestines. Enzymes from the pancreas help in the digestion of carbohydrates, fats and proteins in
the small intestine. It also produces sodium bicarbonate that neutralizes stomach acid as it enters the
small intestine so that the acid does not corrode the small intestine lining. Another part of the
pancreas produces the hormone insulin, which keeps blood sugar (glucose) at the proper levels.
Mixed bag of other terms:
__________________ - food in the stomach that is partly digested and mixed with stomach acids.
Chyme goes on to the small intestine for further digestion.
___________________________ - the flap at the back of the tongue that keeps chewed food from
going down the windpipe (larynx and trachea) to the lungs. When you swallow, the epiglottis
automatically closes. When you breathe, the epiglottis opens so that air can go in and out of the
windpipe.
_________________________ - rhythmic muscle movements that force food in the esophagus and
the other parts of the tube from the mouth to the anus. Peristalsis is involuntary - you cannot control
it. It is also what allows you to eat and drink while upside-down.
___________________________ - glands located in the mouth that produce saliva. Saliva contains
enzymes that break down carbohydrates (starch) into smaller molecules.