Anatomy 1 MCQ PDF

**Lecture 1 -- 34 multiple choice questions:** 1\. Which of the following statements regarding the notochord's role in vertebral development is NOT correct? A. The notochord signals the development of the vertebral column before vertebral segmentation occurs. B. Remnants of the notochord become p...

**Lecture 1 -- 34 multiple choice questions:** 1\. Which of the following statements regarding the notochord's role in vertebral development is NOT correct? A. The notochord signals the development of the vertebral column before vertebral segmentation occurs. B. Remnants of the notochord become part of the nucleus pulposus within the intervertebral discs. C. The notochord directly ossifies to form the vertebral centrum. D. Excess notochordal cells during ossification can result in a butterfly vertebra. E. Insufficient notochordal cells during ossification can contribute to block vertebra formation. Answer: C. Explanation: The notochord does not ossify; it is replaced by vertebral elements formed from mesenchymal cells. Its remnants form the nucleus pulposus. 2\. During which stage of vertebral development do the paired primary centres of chondrification first form, and what do they differentiate into? A. Mesenchymatous stage; perinotochordal sheath B. Cartilaginous stage; centrum and neural arches C. Osseous stage; neural arches and costal elements D. Cartilaginous stage; costal elements and zygapophyseal joints E. Mesenchymatous stage; intervertebral discs Answer: B. Explanation: In the cartilaginous stage (6-9 weeks), paired primary centres of chondrification form the centrum, neural arches, and costal elements. 3\. A neonate presents with scoliosis. Imaging reveals hemivertebrae. Which developmental error most likely caused this condition? A. Failure of re-segmentation during the mesenchymatous stage B. Failure of one primary ossification centre to form in the osseous stage C. Failure of notochordal signalling during the cartilaginous stage D. Persistent neurocentral cartilage beyond 6 years of age E. Excessive Hox10 expression in thoracic vertebrae Answer: B. Explanation: Hemivertebrae occur when one primary cartilage centre fails to form during the cartilaginous stage, causing vertebral asymmetry. 4\. A mutation in Hox10 expression results in which of the following skeletal abnormalities? A. Additional ribs in the thoracic region B. Rib formation in the lumbar region C. Vertebral fusion in the cervical region D. Increased vertebral height due to delayed epiphyseal fusion E. Formation of butterfly vertebrae due to excess notochordal cells Answer: B. Explanation: Loss of Hox10 expression leads to thoracic-isation of the lumbar vertebrae, resulting in rib formation in this region. 5\. In the vertebral development process, failure of segmentation during which stage is most likely to result in block vertebrae? A. Mesenchymatous stage B. Cartilaginous stage C. Osseous stage D. Secondary ossification stage E. Growth plate closure stage Answer: A. Explanation: Block vertebrae result from segmentation failure beginning in the mesenchymatous stage, affecting subsequent cartilage and bone formation. 6\. During the mesenchymatous stage, sclerotome cells migrate to form which of the following vertebral structures? A. Intervertebral discs, annulus fibrosus, and nucleus pulposus B. Centrum, neural arch, and costal element C. Zygapophyseal joints, transverse processes, and mammillary processes D. Cartilage growth plates, interlaminar cartilage, and neurocentral cartilage E. Spinous processes, transverse processes, and ring epiphyses Answer: B. Explanation: Sclerotome cells migrate to form the perinotochordal sheath (centrum), neural arch, and costal elements during this stage. 7\. The presence of interlaminar and neurocentral cartilage growth plates is characteristic of which stage of vertebral column development? A. Mesenchymatous stage B. Cartilaginous stage C. Osseous stage D. Secondary ossification stage E. Growth plate fusion stage Answer: C. Explanation: Interlaminar and neurocentral cartilage are growth plates present in the osseous stage, separating ossification centres. 8\. Which vertebral element contributes to the formation of the zygapophyseal joints and mammillary processes? A. Centrum B. Neural arch element C. Costal element D. Spinous process E. Ring epiphysis Answer: B. Explanation: The neural arch element forms the dorsal arch, zygapophyseal joints, and mammillary processes. 9\. A 12-year-old patient has vertebral anomalies due to a lack of bone deposition at the site of the nucleus pulposus. What is the most likely congenital condition? A. Hemivertebra B. Block vertebra C. Butterfly vertebra D. Thoracic-isation of lumbar vertebrae E. Spina bifida Answer: C. Explanation: Butterfly vertebra results from the persistence of too many notochordal cells, inhibiting bone deposition at the site of the nucleus pulposus. 10\. Which process drives the re-segmentation of somites during vertebral development? A. Notochordal signalling to mesenchymal cells B. Vascularisation and body wall vessel development C. Hox gene expression and intersegmental artery location D. Formation of the nucleus pulposus and annulus fibrosus E. Fusion of neurocentral and interlaminar cartilage Answer: C. Explanation: Re-segmentation is driven by Hox gene expression and the location of intersegmental arteries. 11\. Which of the following accurately describes the mesenchymatous stage of vertebral development? A. Formation of primary ossification centres in the centrum and neural arches B. Migration of sclerotome cells to the perinotochordal sheath, neural arch, and costal elements C. Appearance of secondary ossification centres in the spinous processes and transverse processes D. Differentiation of the notochord into the nucleus pulposus and annulus fibrosus E. Fusion of cartilage growth plates into the vertebral body Answer: B. Explanation: The mesenchymatous stage involves sclerotome migration to form the perinotochordal sheath, neural arch, and costal elements. 12\. Which vertebral anomaly arises due to a failure of one cartilage centre to develop during the cartilaginous stage? A. Butterfly vertebra B. Block vertebra C. Hemivertebra D. Thoracic-isation of lumbar vertebrae E. Lumbar-isation of thoracic vertebrae Answer: C. Explanation: Hemivertebra results from the failure of one cartilage centre during the cartilaginous stage, causing vertebral asymmetry. 13\. The intervertebral discs align with which developmental structure during the cartilaginous stage? A. Neural arches B. Sclerotomes C. Notochordal remnants D. Segments and somites E. Costal elements Answer: D. Explanation: Intervertebral discs develop in line with somite-derived segments, ensuring alignment. 14\. During vertebral segmentation, what defines the location of a vertebral segment? A. Site of intervertebral disc development and nerve root exit B. Position of the neural arch and transverse processes C. Presence of interlaminar cartilage between vertebrae D. Hox gene activation at the thoracic-lumbar boundary E. Position of primary ossification centres in the centrum Answer: A. Explanation: Vertebral segments are defined by intervertebral disc location and where nerve roots emerge. 15\. A patient is diagnosed with butterfly vertebra. What developmental abnormality most likely caused this condition? A. Excess notochordal cells inhibiting bone deposition in the centrum B. Fusion failure of neurocentral cartilage plates C. Loss of Hox10 expression during thoracic-lumbar boundary formation D. Deficient ossification of spinous and transverse processes E. Failure of sclerotome migration during the mesenchymatous stage Answer: A. Explanation: Butterfly vertebra results from excess notochordal cells inhibiting bone deposition in the centrum. 16\. Which vertebral structures form directly from the costal element during development? A. Entire vertebral body and nucleus pulposus B. Ribs in the thoracic region and transverse processes in other regions C. Neural arches and zygapophyseal joints D. Spinous processes and mammillary processes E. Intervertebral discs and annulus fibrosus Answer: B. Explanation: The costal element forms ribs in the thoracic region and contributes to transverse processes in other regions. 17\. How does the notochord contribute to vertebral development during the cartilaginous stage? A. It signals segmentation of somites into vertebral bodies and discs. B. It forms the nucleus pulposus of the intervertebral discs. C. It creates Hox gene expression patterns for rib formation. D. It induces the appearance of secondary ossification centres. E. It becomes segmented into individual vertebral arches. Answer: B. Explanation: The notochord forms the nucleus pulposus, with fibrocartilage forming the surrounding annulus fibrosus. 18\. Which of the following is a direct consequence of Hox10 gene deletion in vertebral development? A. Excessive rib formation in the lumbar and sacral regions B. Increased height of the vertebral bodies at puberty C. Fusion of the neural arches during the osseous stage D. Retention of mesenchymal cells in the perinotochordal sheath E. Reduction in thoracic vertebrae due to lumbarisation Answer: A. Explanation: Loss of Hox10 expression causes thoracic-isation, with rib formation in the lumbar and sacral regions. 19\. What is the significance of neurocentral cartilage growth plates in vertebral development? A. They allow the ribs to attach to transverse processes. B. They separate primary ossification centres in the vertebral body and neural arches. C. They differentiate into secondary ossification centres in the spinous processes. D. They contribute to the formation of the intervertebral disc's annulus fibrosus. E. They signal the re-segmentation of somites into intervertebral structures. Answer: B. Explanation: Neurocentral cartilage growth plates separate ossification centres in the vertebral body and neural arches during development. 20\. In the osseous stage, which process contributes to the continuation of vertebral growth beyond birth? A. Formation of secondary ossification centres in the ring epiphysis B. Closure of interlaminar and neurocentral cartilage growth plates C. Proliferation of hyaline cartilage in the costal elements D. Persistence of intersegmental arteries between vertebrae E. Deposition of bone towards the vertebral body endplates Answer: A. Explanation: Secondary ossification centres in the ring epiphysis contribute to vertebral growth during the osseous stage. 21\. What is the primary clinical manifestation of block vertebra? A. Loss of mobility between fused vertebral segments B. Presence of a hypoplastic vertebral arch C. Structural scoliosis due to vertebral asymmetry D. Rib anomalies in the thoracic region E. Compression of intersegmental arteries Answer: A. Explanation: Block vertebra causes reduced mobility due to the fusion of vertebral segments. 22\. What distinguishes the neural arch element in vertebral development? A. It forms the entirety of the vertebral body. B. It contributes to the dorsal arch, zygapophyseal joints, and lateral vertebral body. C. It fuses with the costal element to create the nucleus pulposus. D. It signals the segmentation of sclerotome cells into somites. E. It differentiates into the spinous processes and transverse processes. Answer: B. Explanation: The neural arch element forms the dorsal arch, zygapophyseal joints, and contributes to the lateral vertebral body. 23\. What distinguishes the mesenchymatous stage from the cartilaginous stage in vertebral development? A. Formation of sclerotome cells into primary ossification centres. B. Migration of sclerotome cells into perinotochordal and neural arch regions. C. Replacement of mesenchyme with hyaline cartilage. D. Development of intervertebral discs from Hox gene expression. E. Fusion of interlaminar cartilage plates. Answer: C. Explanation: The cartilaginous stage is marked by the replacement of mesenchyme with hyaline cartilage, forming vertebral structures. 24\. During the osseous stage, which process is responsible for continuing vertebral growth after birth? A. Proliferation of primary ossification centres in costal elements. B. Closure of neurocentral cartilage growth plates. C. Growth of the ring epiphysis, contributing to vertebral body height. D. Segmentation of somites into vertebral bodies. E. Hyaline cartilage differentiation into neural arches. Answer: C. Explanation: Growth of the ring epiphysis allows vertebral bodies to continue growing in height during the osseous stage. 25\. Which Hox gene expression error is associated with lumbar-isation of thoracic vertebrae? A. Loss of Hox10 expression in lumbar segments. B. Gain of Hox10 expression in thoracic segments. C. Loss of Hox6 expression in cervical regions. D. Gain of Hox11 expression in lumbar segments. E. Gain of Hox8 expression in sacral regions. Answer: B. Explanation: Gain of Hox10 expression causes lumbar-isation of thoracic vertebrae. 26\. What developmental process ensures nerve roots exit between vertebrae? A. Migration of notochordal cells into nucleus pulposus. B. Alignment of segments with intervertebral discs during somite re-segmentation. C. Appearance of secondary ossification centres at puberty. D. Formation of interlaminar cartilage between spinous processes. E. Fusion of costal elements to vertebral bodies. Answer: B. Explanation: Somite re-segmentation aligns intervertebral discs with nerve root exit sites. 27\. Failure of segmentation during which stage contributes to block vertebra? A. Cartilaginous stage B. Mesenchymatous stage C. Osseous stage D. Secondary ossification stage E. Ring apophysis stage Answer: B. Explanation: Block vertebrae result from segmentation failure during the mesenchymatous stage, affecting later cartilage and bone formation. 28\. Which vertebral structure forms exclusively from the costal element? A. Zygapophyseal joints in the thoracic vertebrae. B. Ribs in the thoracic region and parts of the transverse process in other regions. C. Spinous processes in lumbar and thoracic vertebrae. D. Entire vertebral bodies in the cervical region. E. Ring epiphysis in lumbar vertebrae. Answer: B. Explanation: The costal element contributes ribs in the thoracic region and transverse processes elsewhere. 29\. What clinical condition may result from the persistence of neurocentral cartilage after 8 years of age? A. Scoliosis due to asymmetry in vertebral height. B. Failure of vertebral body fusion, leading to hemivertebrae. C. Thoracic-isation of lumbar vertebrae. D. Butterfly vertebra due to notochordal persistence. E. Structural weakness in the vertebral arch. Answer: E. Explanation: Persistent neurocentral cartilage can affect the integrity of the vertebral arch. 30\. A neonate presents with thoracic ribs extending into the lumbar region. Which developmental process is most likely disrupted? A. Notochord segmentation during the mesenchymatous stage. B. Hox gene expression during thoracic-lumbar differentiation. C. Failure of neural arch ossification in the cartilaginous stage. D. Excess neurocentral cartilage retention in thoracic segments. E. Migration of sclerotome cells into costal elements. Answer: B. Explanation: Disrupted Hox10 expression leads to thoracic-isation, with ribs extending into the lumbar region. 31\. What is the role of the nucleus pulposus in intervertebral disc function? A. Prevents vertebral fusion during mesenchymatous development. B. Facilitates segmentation by separating vertebral elements. C. Acts as a remnant of the notochord, providing shock absorption. D. Directly ossifies to contribute to vertebral height. E. Promotes bone deposition in the annulus fibrosus. Answer: C. Explanation: The nucleus pulposus, a remnant of the notochord, provides shock absorption within intervertebral discs. 32\. Which of the following secondary ossification centres is responsible for increasing vertebral height during puberty? A. Spinous processes B. Ring epiphysis C. Mammillary processes D. Neurocentral cartilage E. Costal elements Answer: B. Explanation: Ring epiphysis contributes to the vertical growth of vertebral bodies during puberty. 33\. Which condition results from excess nucleus pulposus formation during development? A. Block vertebra B. Butterfly vertebra C. Hemivertebra D. Spina bifida E. Thoracic-isation Answer: B. Explanation: Excess nucleus pulposus due to notochordal cell persistence causes butterfly vertebra. 34\. What distinguishes vertebral growth plates from epiphyseal plates in long bones? A. Vertebral growth plates ossify earlier than epiphyseal plates. B. Vertebral growth plates allow circumferential rather than linear growth. C. Vertebral growth plates persist until age 8, unlike epiphyseal plates. D. Vertebral growth plates do not ossify but transform into costal elements. E. Vertebral growth plates do not influence height growth in vertebrae. Answer: C. Explanation: Neurocentral and interlaminar growth plates close by age 8, distinguishing them from long bone epiphyseal plates.