Digestive System

Question 1

List some functions of the digestive system and the 3 main parts

Answer 1

Securing food
Conducting and storing food
Mechanical/chemical digestion
Absorption of food
Storage and disposal of wastes

3 mains parts= mouth, pharynx, alimentary canal

Question 2

T/F:

Areas for digestion have high pH

Answer 2

False
Low pH
(areas for absorption have high pH)

Question 3

Distinguish between the oral cavity proper and the oral vestibule

Answer 3

Oral cavity proper= space between palate, teeth/gums, tongue on floor of cavity

Vestibule= space between the teeth and lips/cheeks

Question 4

Which two systems are crossed over by the pharynx?

Answer 4

Digestive system and respiratory system

Question 5

T/F:

Food is conveyed from the mouth to the oesophagus by the larynx via deglutition

Answer 5

False

By the pharynx

Question 6

What are the four main structures of the alimentary canal?

Answer 6

Oesophagus
Stomach
Small intestine
Large intestine

Question 7

What is the main different between the small and large intestine in terms of what they absorb?

Answer 7

Small= carbohydrates, proteins and fat

Large= absorption, fermentation of plant material in the caecum

Question 8

Describe the general divisions of the abdomen

Answer 8

Cranial: xiphoid, left and right hypochondrial regions
Middle: umbilical, left and right flank regions
Caudal: pubic, left and right inguinal regions

Question 9

Describe the boundaries of the abdominal cavity

Answer 9

Refer to notes

Question 10

T/F:

The lateral boundary of the abdominal cavity is bounded by the left and right rectus abdominus muscles

Answer 10

False
Lateral boundary is bounded by the diaphragm and the ext. oblique, in. oblique and transverse abdominal muscles
Parts of the pelvis (wing of ilium)

Ventral boundary is bounded by the left and right rectus abdominus muscle

Question 11

T/F:

The peritoneum is composed of simple cuboidal mesothelium

Answer 11

False

simple squamous mesothelium

Question 12

What is the function of the peritoneum?

Answer 12

Secretes peritoneal fluid which acts as a lubricant to prevent friction between opposing surfaces

Question 13

What is the peritoneal cavity further divided into?

Answer 13

Peritoneal cavity and pelvic portion

Question 14

List some examples of connecting peritoneum (composed of double membranes)

Answer 14

Mesentery
Greater/lesser omentum
Ligaments

Question 15

T/F:

An empty dog stomach is in contact with the abdominal wall

Answer 15

False

Question 16

When the dog stomach is moderately filled, where does it lie?

Answer 16

Against the xiphoid and left hyochondrial region

Question 17

Would you find the uterus more ventrally or more dorsally and why?

Answer 17

Ventrally

Not filled with air so it is heavy

Question 18

T/F:

Tooth sockets are located in the mandible and maxilla

Answer 18

False

Located in alveolar bone

Question 19

T/F:

Palatine surface is a feature of both upper and lower teeth

Answer 19

False

Just upper

Question 20

List the surfaces of the teeth

Answer 20

Buccal= facing the cheek
Lingual= facing the tongue
Palatine= facing the palate
Occlusal= masticatory surface, where the two partner teeth come into contact with each other
Interproximal/interdental= facing adjacent teeth in the same arcade/row

Question 21

Describe the differences between brachydont and hypsodont teeth and relate this to function

Answer 21

see notes

Question 22

T/F:

The neck structure is present in hypsodont teeth only

Answer 22

False
only present in brachydont teeth
Slight constriction at the cementoenamel junction

Question 23

T/F:

The root is covered in enamel

Answer 23

False

Not covered in enamel

Question 24

Which cells product enamel, dentine and cementum?

Answer 24

Enamel= ameloblasts
Dentine= odontoblasts
Cementum= cementoblasts

Question 25

T/F: Ameloblasts create enamel and persist after eruption

Answer 25

False

Lost after eruption

Question 26

When is secondary dentine laid down?

Answer 26

After root formation

Question 27

How do odontoblasts contribute to sensitive teeth?

Answer 27

Their processes extend into the dentine, damage to the dentine can transmit this to the nerves in the pulp cavity

Dentine at the occlusal surface of horse teeth is not sensitive

Question 28

Describe dental pulp

Answer 28

Connective tissue with blood vessels

Nerves/BVs enter through the apical foramen

Question 29

Which nerves are found in the pulp cavity and where do they come from?

Answer 29

Superior alveolar= maxillary division of trigem

Inferior alveolar= mandibular division of trigem

Question 30

Where is the periodontal ligament attached to and what is its function?

Answer 30

Alveolar bone to the cementum surrounding the root of the tooth
Suspends the tooth in the alveolus
Some shock absorbing to accomodate compression during chewing

Question 31

What is the periodontal ligament comprised of and which cells make it?

Answer 31

Comprised of collagen fibres called Sharpeys fibres

Made by fibroblasts

Question 32

Which species usually are monophyodont?

Answer 32

Most species of rodents

Question 33

Which species usually are polyphyodont?

Answer 33

Elephant

Most other vertebrates

Question 34

T/F:

Tooth eruption is quite fast in hypsodont teeth and commences after root formation

Answer 34

False
Slow
Comments before root formation