Digestive System Pt 1. - Oral Cavity

Question 1

Where does the digestive system begin and what type of digestion is it?

Answer 1

At the oral cavity and goes into the pharynx
* Mechanical digestion in the O. cavity

Goes into esophagus after passing the pharynx

Question 2

What is the path of food after it goes from the esophagus?

Answer 2

1. Stomach
2. Small intestine - Duodenum, Jejunum & Ileum
3. Cecum - small intestine empties into large & first part of cecum
4. Ascending, Transverse and Descending Colon - from the cecum
5. Sigmoid colon - posterior part of large intestine
6. Rectum, Anal Canal & Anus

Question 3

How many baby teeth do we initially have and what are the groups they are split into and how many teeth?

Answer 3

20 teeth
* 4 central incisors upper and lower (8 total)
* 2 canine teeth (4 total)
* 4 First and Second Molar (8 total)

Note: 2 pairs for each (top and bottom)

Question 4

How many more adult teeth are there compared to baby? What are the pairs and how many?

Answer 4

32 total compared to 20

• 2 pairs of central incisors (8 total)
• 2 pairs of first and second premolar - new teeth (8 total)
• 2 pairs of canine (4 total)
• 2 pairs of first and second molar - (8 total)
• 4 pairs of third molar (a.k.a. wisdom teeth) - new teeth (4 total)

Note: equal set of teeth for each pair on the upper and lower part of the oral cavity

Question 5

Purpose of third molar and why it tends to be removed?

Answer 5

As cavemen, used this to eat leaves and other things that required a lot of grinding, but now that we don’t need that we get them removed because its hard to get cleaned

Question 6

What are salivary glands?

Answer 6

• Produce saliva which is water based but contain digestive enzymes to breakdown food
• exocrine glands which contain ducts that carries saliva from the gland to their destinations

Note: chemical breakdown of food

Question 7

What are the different salivary glands and where are they located

Answer 7

1. Parotid - anterior-inferior to ears
2. Submandibular - floor of oral cavity (beneath the
   base of the tongue, are medial and partly inferior to the mandible)
3. Sublingual - floor of oral cavity (superior to the submandibular glands)

Question 8

Where do the submandibular duct open?

Answer 8

Travels to the front of the oral cavity & comes up under the tongue

Question 9

Where does the sublingual duct open?

Answer 9

Travels through multiple ducts that are open under the tongue in the floor of the oral cavity

Question 10

Where does the parotid duct open at?

Answer 10

Travels inside the teeth and pierce muscles of teeth to travel into oral cavity

Question 11

Based on the picture explain how the salivary glands work

Answer 11

The glands have storage spaces for the chemical enzymes which collectively form and move out of the salivary ducts into the oral cavity

Question 12

What is the tongue’s function?

Answer 12

1. Rooted to the floor of the mouth
2. Tip of tongue helps with speaking
3. Helps in mechanical digestion by moving food around to the teeth

Question 13

What are papilae?

Answer 13

• Bumps on tongue
• Important for mechanical breakdown and digs things out of teeth that are stuck
• Another form of papilae contains taste buds (special receptors for taste related food)
• Attached to cranial nerves

Question 14

What is the lingual frenulum?

Answer 14

Limits the movement of the tongue posteriorly, underneath the tongue

Question 15

What is found on the bottom of the lingual frenulum?

Answer 15

Opening of the duct of the submandibular gland & openings of sublingual ducts