MDS PREP
Immediately following the closure of the A-V valves is the period of
1. Isotonic contraction
2. Isometric contraction
3. Isometric relaxation
4. Isotonic relaxation
Anatomy
Answer: 3
Immediately following the closure of the A-V valves is the period of
Isometric relaxation
The trigeminal ganglion lies on
1 Anterior temporal bone near its apex hi Meckel’s cave, which is a depression in the bone
2. Posterior surface of petrous temporal bone near Its apex in -Meckel’s cave. which is a depression In the bone
3. Anterior surface of petrous temporal bone near its apex in Meckel’s cave which is a space of dura mater
4. Petrous temporal bone in posterior cranial fossa
Anatomy
Answer: 3
The trigeminal ganglion lies on Anterior surface of petrous temporal bone near its apex in Meckel’s cave which is a space of dura mater
The beginning of active eruption of a human tooth occurs
1. before the root has begun to develop
2. coincidental with the beginning of root formation
3. before the root has begun to develop
4. after one half of the root is formed
Dental Anatomy
Answer: 4
The beginning of active eruption of a human tooth occurs after one half of the root is formed
The primary canine is usually exfoliated between the ages of
1. 5 and 6 years
2. 10 and 11 years
3. l3 and l4years
4. 8 and 9years
Dental Anatomy
Answer: 2
The primary canine is usually exfoliated between the ages of 10 and 11 years
A wound to the posterior left axillary line, between the ninth and tenth rib, and extending approximately 5 cm deep, will most likely damage which organ?
1) Ascending colon
2) Duodenum
3) Left kidney
4) Spleen
Anatomy
Answer: 4
The spleen follows the long axes of ribs 9 to 11 and lies mostly posterior to the stomach, above the colon, and partly anterior to the kidney. It is attached to the stomach by a broad mesenterial band, the gastrosplemic ligament. Therefore, it is the most likely organ of the group to be pierced by a sharp object penetrating just above rib 10 at the posterior axillary line. Note that the pleural cavity, and possibly the lower part of the inferior lobe of the lung, would be pierced before the spleen. The ascending colon (choice 1) is on the wrong side (the right) to be penetrated by a sharp instrument piercing the left side.
Most of the duodenum (choice 2) is positioned too far to the right to be affected by this injury.
Even the third part of the duodenum, which runs from right to left, would still be out of harm's way. In addition, the duodenum lies at about levels L1 to L3, placing it too low to be injured in this case.
The superior pole of the left kidney (choice 3) is bordered by the lower part of the spleen. However, it is crossed by rib 12 and usually does not extend above rib 11. It would probably be too low and medial to be injured in this case because this penetration is at the posterior axillary line.
The most common site for CSF rhinorrhea
1. frontal bone
2. ethmoid bone
3. tegmen tympani
4. none
Anatomy
Answer: 2
Cerebrospinal fluid (CSF) rhinorrhea occurs when there is a leak of CSF through the nasal cavity, often due to a defect in the skull base. The ethmoid bone is the most common site for such leaks because of its thin structure and proximity to the nasal cavity.
The secretory product of odontoblasts is:
1) Topocollagen.
2) Calcium salts.
3) Mantle dentin.
4) Hydroxyapatite
Dental Anatomy
Answer: 3
Dentinogenesis is the formation of dentin by odontoblasts of mesenchymal origin
located at the periphery of the dental pulp
Dentinogenesis is initiated by the inductive influence of the enamel organ
involving molecular signaling pathways, such as Wnt, Runx-2, and TGF-?. In the
molar tooth, dentinogenesis starts at the late bell stage, and occurs in the
crown as well as root regions.
Predentin, the first organic matrix secreted by odontoblasts, is composed by
proteoglycans, glycoproteins, and collagens.