L3 chewing and swallowing

Question 1

where does the oesophagus pierce the diaphragm?

Answer 1

oesophageal hiatus (enters abdomen)

Question 2

what nerve innervates the oesophagus?

Answer 2

vagus (10th cranial)

Question 3

which layer of the oesophagus has mucous secreting cells?

Answer 3

sub-mucosa

Question 4

what muscle is the muscularis of the oesophagus?

Answer 4

superior 1/3 = skeletal muscle
middle 1/3 = transitional
inferior 1/3 = SMC

Question 5

where is the hypopharyngeal sphincter?

Answer 5

upper oesophagus

Question 6

where is the gastro-oesophageal sphincter?

Answer 6

lower oesophagus

Question 7

what is gustation?

Answer 7

taste

Question 8

what type of receptor are taste buds?

Answer 8

chemoreceptor

Question 9

what are the 4 types of taste buds and where do you find them?

Answer 9

1. filiform (don’t taste)
2. fungiform (dorsal surface of tongue)
3. foliate (tips and side of tongue)
4. circumvallate (intersection of anterior/posterior tongue)

Question 10

what is aguestia?

Answer 10

loss of taste

Question 11

what is phenylthiourea?

Answer 11

inability to taste bitterness

Question 12

3 pairs of salivary glands and their output?

Answer 12

1. parotid (serous) (water and alpha amylase)
2. submandibular (serous and mucous) (weak alpha amylase and lysozyme)
3. sublingual (mucous) (thick, viscous secretion)

Question 13

what is saliva composed of?

Answer 13

90% water, <1% ions and over 50 proteins

Question 14

pH of salvia?

Answer 14

6. 8 at low flow rate

8. 0 at high flow rate

Question 15

rate of saliva production?

Answer 15

0.05ml/min at rest

7ml/min sour stimulation

Question 16

how much salvia to we produce in a day?

Answer 16

1-2L

Question 17

What is mumps?

Answer 17

infection of parotid gland by myxovirus

Question 18

what is xerostomia?

Answer 18

dry mouth

Question 19

what is deglutition?

Answer 19

swallowing

Question 20

what are the 3 phases of deglutition?

Answer 20

1. voluntary
2. pharyngeal (activates pressure receptors in palate and anterior pharynx, impulses in trigem and glossophar nerves -> swallowing centre in medulla oblongata - causes elevation of soft palate and inhibition of respiration and closure of glottis (sealing airway)).
3. Oesophageal (peristalsis (circular SMC), vagus nerve)

Question 21

what is gastro-oesophageal reflex disease?

Answer 21

• gastric contents into oesophagus (heartburn)