Digestive System Flashcards
In the digestive system, food undergoes two changes, what are they?
Mechanical and chemical transformations.
What are the four stages of digestion?
- Ingestion of food
- Digestion of food
- Absorption of Nutrients
- Elimination of substances that have not been absorbed
Can water, minerals, and vitamins be absorbed into the bloodstream without being digested?
Yes, since they aren’t complex molecules.
Can carbohydrates, proteins, and fats be absorbed directly into the bloodstream?
No, because they’re molecules are so complex that they have to be digested into smaller molecules.
Can carbohydrates, proteins, and fats be absorbed directly into the bloodstream?
No, because they’re molecules are so complex that they have to be digested into smaller molecules.
When does digestion start?
When food is smelt or seen before it is eaten/ingested.
What do Salivary glands do?
They produce saliva, which helps transform the complex molecules of carbohydrates into simpler ones.
Is transforming the complex molecules of carbs into simpler ones a Mechanical or Chemical transformation?
Chemical transformation, because the nature is being changed.
What does the tongue help with?
Moves food around while you masticate (chew) and breaks down food into smaller pieces with your teeth.
Is breaking food into smaller pieces a Mechanical or Chemical transformation?
Mechanical, because the nature of the food isn’t being changed.
What is another term for mushed-up food?
Bolus.
What is the esophagus and what does it do?
An esophagus is like a stretchy pipe, roughly 10 inches long, this moves food from your throat into your stomach through muscle contractions know as peristalsis.
When food is moved from the back of the throat into your stomach, what kind of transformation is this?
Mechanical transformation, because the nature isn’t being changed.
What are the rhythmic muscle contractions of your esophagus called to help food move along?
Peristalsis.
True or false: Is the stomach attached to the esophagus?
True.
The stomach has three main jobs, what are they?
- Store food
- Break down the larger molecules into simpler ones
- Empty the liquid mixture into the small intestines
The stomach is often compared to a mixer, mixing all the small balls of bolus into smaller pieces, is this a mechanical or chemical transformation?
Mechanical transformation, the nature doesn’t change.
What are gastric juices, and what do they do?
Liquid secreted by the glands along the stomach’s walls, this helps break down proteins.
When gastric juices break down protein, is this a mechanical or chemical transformation?
Chemical transformation, because the nature is being changed. The protein is being broken down into peptides and amino acids, which can easily enter the small intestines.
What do the small intestine do?
When food enters the small intestine, the intestinal glands secrete intestinal juices that transform proteins into amino acids and fats into smaller molecules (chemical transformation). The small intestine also churns (mix) and moves food along through peristalsis.
The small intestine is lined with villi, what do they do?
Allows some nutrients to be absorbed into the bloodstream, if needed (diffusion)
What does the liver do?
Secretes bile in the gallbladder and emulsifies fats (separates water and fats)
Is emulsifying fats a mechanical or chemical transformation?
Mechanical, the nature isn’t being changed.
What does the pancreas do?
Secretes pancreatic juices that break down carbohydrates into smaller molecules of glucose.
When pancreatic juices break down carbohydrates, what kind of transformation is this?
Chemical transformation, the nature is being changed.
True or False: Are the liver & pancreas glands?
True.
What does the large intestine do?
This is where most water, nutrients, and minerals are absorbed into the bloodstream.
When all the nutrients needed are absorbed into the bloodstream what happens with the rest?
It transforms into a solid which is then expelled through the anus. (Physical transformation)
