Science 13 Flashcards
(19 cards)
Explain the different functions of the incisors, canines, and molars.
Incisors cut food like a knife, while canines tear it like a fork. The molars crush and grind food.
What teeth are the last ones to come in? What are they commonly called?
Your third set of molars is the last to come in, and those molars are often called your wisdom teeth.
What are the four functions of saliva?
It starts the chemical digestion, moistens food, allows you to taste things, and helps kill pathogens that might be on the food.
Describe what the soft palate and the epiglottis do when you swallow something.
The soft palate blocks the opening between the throat and nose so that food doesn’t go up your nose. The epiglottis blocks off the larynx so that food doesn’t enter the trachea.
What is the wet ball of food that is swallowed called?
It is called a bolus.
If you were standing on your head and swallowed something, would it go to your stomach? Why or why not?
Yes, it would. The smooth muscles of the esophagus push the food to the stomach. It doesn’t matter where your stomach is relative to your mouth.
What are sphincters?
They are rings of muscle that open and close things like the esophagus, stomach, small intestine, etc.
Why must the acid in the food be neutralized in the small intestine?
The digestive enzymes in the small intestine do not work well in the presence of acid.
In which organ of the digestive tract does most of the digestion take place?
The small intestine.
For the mouth, esophagus, stomach, and small intestine indicate whether chemical digestion, physical digestion, both, or neither happens in each.
In the mouth, it’s both. In the esophagus, it’s neither. In the stomach, it’s both. In the intestine, it’s chemical.
For the mouth, esophagus, liver, stomach, pancreas, small intestine, gall bladder, and large intestine, indicate whether each is part of the digestive tract or an accessory digestive organ.
The mouth, esophagus, stomach, small intestine, and large intestine are all organs of the digestive tract. The liver, pancreas, and gall bladder are accessory digestive organs.
What do the gastric rugae allow the stomach to do?
They allow the stomach to expand in size as it fills with food.
How are soap and bile similar? Why is that important for the digestion of fat?
They both emulsify nonpolar compounds. This is important so that there is a lot of surface area for the fat that is in the small intestine. That speeds up chemical digestion.
What two things happen to the chyme when it reaches the large intestine?
Water is removed from it, and bacteria digest whatever chemicals they can use.
What do the intestinal villi do for absorption of nutrients in the small intestine?
They increase the surface area of the small intestine to speed up absorption.
The body uses the chloride ion for certain functions. Does that mean the kidneys will never take chloride from the blood? Why or why not?
No. The kidneys will remove chloride ions if they are at too high a concentration.
One kind of physician is called a nephrologist. What does this doctor specialize in?
He or she specializes in kidneys.
Compare how the kidneys clean blood to how some people clean out their junk drawer.
The kidneys take everything out of the blood and then return to the blood what is needed. Anything left over is then put in the urine. This is similar to dumping the contents of a drawer on a counter, putting back the things you want to keep, and throwing away anything left on the counter at the end.
If your urine is unusually thin and not very yellow, have you been drinking more or less water than usual?
You have been drinking more water than usual.
