digestive system quiz Flashcards
what are the four stages of food processing?
- ingestion
- digestion
- absorption
- elimination
what is ingestion?
the taking in or eating food
what is digestion?
The breakdown of food by mechanical and chemical processes that form small molecules for the cells of the body to absorb
what is absorption?
transporting and absorbing nutrients into blood stream .
what is elimination?
the removal of undigested solid waste matter from the body
what is mechanical digestion?
A physical breakdown of the food into smaller pieces
what is an example of mechanical digestion?
food enters your mouth and is physically broken down to smaller pieces by your teeth or your stomach churning
what is chemical digestion?
uses certain enzymes to break down nutrients, into smaller molecules
what is an example of chemical digestion?
when our saliva that contains enzymes, break down biomolecules
what organs are in involved in ingestion?
mouth, teeth, and esophagus
what organs are in involved in digestion?
mouth, stomach, and small intestine
what organs are in involved in absorption?
stomach and large intestine
what organs are in involved in elimination?
large intestine, rectum, and anus
what is the alimentary canal?
a tube through which food is processed
what happens in the alimentary canal?
This long tube of organs makes a pathway for food to travel through the body. It runs from the mouth to the anus
why must we digest?
we have to break down nutrients in foods to a form where its small enough to fit into our cells and be usable by the cells
what are the two kids of digestion?
mechanical and chemical digestion
what do organisms require to preform life functions and obtain energy?
nutrients
where can organisms that require nutrients obtain energy?
macromolecules
what are macro molecules?
larger and more complex organic molecules, that are composed of smaller molecules, link together
what are the 4 categories of macromolecules?
- carbohydrates
- lipids
- proteins
- nucleic acids
what is the main function of carbohydrates?
provide quick energy for use by body
what is the main function of lipids?
its a long term energy storage and uses material to build a cell membrane
what is the main function of proteins?
it give structure and support, it has catalysts to speed up chemicals, it transports ions in cell membrane
what is the main function of nucleic acids?
contains genetic information and directs organisms growth
what is an example of carbohydrates?
glucose and fructose
what is an example of lipids?
fats, oils, waxes
what is an example of proteins?
insulin, hemoglobin, enzymes, and collagen
what is an example of nucleic?
DNA and RNA
what are the four types of tissue?
connective tissue, epithelial tissue, muscle tissue, and nervous tissue
what are the 4 structurally organized levels of the human body?
- cells
- tissues
- organs
- organ systems
what are enzymes?
a protein that helps to speed up chemical reactions in the body.
what is hydrolysis?
a chemical reaction in w which water breaks apart macromolecules into smaller molecules
what are accessory organs?
pancreas, liver and gall bladder
what do theses accessory organs do?
release fluids into the canal that are essential for digestion
what does the pancreas do?
Produces insulin and secretes 1L of pancreatic fluid per day
what does Pancreatic fluid contain?
1) Base (bicarbonate) – to neutralize stomach acid
2) Enzymes – to chemically digest proteins carbohydrates and lipids
what are Monosaccharides?
a single carbohydrate unit known to be
“simple sugar”
what are Disaccharides?
a sugar made up of 2
monosaccharide molecules
Polysaccharides?
large molecule made of
many monosaccharides
what are proteins made of?
Made from small sub-units called amino acids. Amino acids are joined by peptide bonds into one or more chains
where does digestion start?
it starts in the mouth. Where the teeth breaks down food into small pieces (mechanical digestion) to make it more assessable to go down the esophagus
what are the roles of water in the body?
- transporting dissolved nutrients
- flushing toxins from cells
- lubricating tissues and joints
- eliminating waste materials (in urine and sweat)
what happens in the mouth?
Salivary glands in the mouth secrete saliva to begin chemical digestion. Teeth begin the process of mechanical digestion, and the tongue helps turn the food into a soft bolus
what does does the alimentary canal contain?
*mouth
*esophagus
*stomach
*small intestine
*large intestine
*rectum/anus
what kind of teeth do carnivores have?
In carnivores such as the
dog, “canine” teeth
specialized for ripping food
are more common.
what kind of teeth do herbivores have?
Herbivores like deer have
grinding teeth to eat
grass/leaves.
what kind of teeth do snakes have?
Snake teeth slope backwards to
help them hold their prey during
swallowing
what happens in the esophagus ?
The esophagus transports the
bolus to the stomach by
wave-like muscular contractions
called peristalsis
Mucus keeps the passage moist.
what happens after you swallow the boules from chemical/mechanical digestion in the mouth?
The bolus is swallowed and enters the esophagus. The epiglottis at the top of the wind pipe (next to the esophagus) closes to ensure the bolus does
not enter the lungs
what IS the stomach?
a J-shaped organ that Lies on left side of abdominal cavity, Just below the diaphragm
what is diaphragm?
sheet of muscle that separates the heart, lungs, and ribs from
the abdominal cavity
what happens in the stomach?
Entrance of stomach controlled by a ring of muscle called the esophageal sphincter. There are glands in the stomach that secrete gastric juice. Pepsin Breaks protein into small
polypeptides. Stomach has 3 layers of muscle fibers that contract/relax to physically churn food. The wall for the stomach expand. Food forms a thick liquid called chyme. Chyme exits the stomach through a muscular valve called pyloric sphincter
what happens in the small intense?
further break down macromolecules and ABSORB nutrients through cells. Moves food through path using peristalsis. Contractions squeeze chyme and break up food
how long is a small intestine?
Small intestine would be about 6 meters long (20 feet) if stretched out!!
what are the 3 parts of the small intestine?
1) The duodenum
2) The jejunum
3) The ileum
what happens in the duodenum?
Duodenum receives secretions from the pancreas and gall bladder
what are accessory organs?
Pancreas, liver and gall bladder are not part of the alimentary canal (food does not
travel through them). But they do aid in digestion
what are enzyme functions in chemical digestion?
1) Carbohydrase digest carbs
2) Lipases digest lipids
3) Proteases digest proteins
4) Nucleases digest nucleic acids
what is the liver?
the liver Secretes bile. Bile is produced in the liver, and stored in the gall bladder.
what is bile?
a greenish-yellow fluid
Made of bile pigments and bile salts
what do bile salts digest?
fats
what is the pancreas?
Pancreas secretes pancreatic fluid into duodenum.
what is the Jejunum?
Contains even more folds than the duodenum. Breaks down the remaining proteins and carbohydrates
what is the Ileum?
Its function is to absorb nutrients. it will push any remaining undigested material into the large intestine
Digestion of carbohydrates starts in the….
mouth
Digestion of lipids starts in the…
oral cavity
Digestion of proteins and nucleic acids starts in the….
the stomach
what happens in the large intestine?
Much shorter/wider than small
intestine. Main function of colon is to absorb water back into blood. Remaining indigestible matter is sent to rectum
what are the 3 portions on the large intestine?
- Ascending colon (larger part)
- Transverse colon (middle)
- Descending colon (near rectum)
what vitamins do the large intestine produce?
vitamins B and vitamin K
what happens in the rectum/anus?
Waste travels through rectum and exits body through anus.
Signals are sent from brain to trigger an urge to go to the bathroom.
what is the anal sphincter?
group of muscles surrounding the anus that controls release of stool
what are the symptoms of constipation?
Bowel movements reduced to 3 times/week or less, stools are dry, small and difficult to eliminate.
what is the cause of constipation?
Lack of good nerve & muscle function in bowel Unhealthy diet, lacking fiber, Lack of physical activities
what is the treatment for constipation?
Eat fiber-rich foods (whole grain bread, rice, beans, peas, lentils, flax, vegetables, etc.)
