Human Anatomy - Problem Drill 06: The Skeletal System Axial Skeleton & Articualtions

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1 Human Anatomy - Problem Drill 06: The Skeletal System Axial Skeleton & Articualtions Question No. 1 of 10 Instructions: (1) Read the problem and answer choices carefully, (2) Work the problems on paper as 1. Which of the following statements about the axial skeleton is correct? Question #01 (A) The axial skeleton includes the vertebral column and the bones of the upper limbs. (B) The major functions of the axial skeleton include protecting the brain and the organs of the thorax. (C) The axial skeleton includes the bones of the skull and the pelvic girdle. (D) The axial skeleton plays no role in the breathing cycle. (E) Adjusting the position of the head and neck is not part of the function of the axial skeleton. The bones of the upper limbs are part of the appendicular skeleton. B. Correct! The major functions of the axial skeleton include protecting the brain and the organs of the thorax, providing surfaces for the attachment of muscles in the region, adjusting the position of the head and neck, and playing a role in the breathing cycle. The pelvic girdle is part of the appendicular skeleton. The axial skeleton does contribute to breathing. The first two cervical vertebrae facilitate the movements of the head and neck. The two major divisions of the skeletal system are the appendicular skeleton and the axial skeleton. The axial skeleton includes the bones of the skull, inner ear bones, vertebral column and the bones of the thorax. The major functions of the axial skeleton include: (1) protecting the organs in the thorax, as well as the brain, (2) providing surfaces for the attachment of muscles in the region, (3) adjusting the position of the head and neck, and (4) playing a role in the breathing cycle. (B)The major functions of the axial skeleton include protecting the brain and the organs of the thorax.

2 Question No. 2 of 10 Instructions: (1) Read the problem and answer choices carefully, (2) Work the problems on paper as 2. What part of the vertebrae in the image below is labeled with the letter A? A Question #02 (A) Spinous process. (B) Transverse process. (C) Vertebral body. (D) Vertebral arch. (E) One of the two spinous processes. The spinous process is the process at the most posterior part of the vertebra. B. Correct! The letter A identifies one of the two transverse processes. The vertebral body is the round, thick anterior portion of the vertebra. The vertebral arch is connected to a transverse process. The letter A identifies one of the two transverse processes. Spinous Process Transverse Process Vertebral Arch Vertebral Body Vertebral Foramen The vertebrae in the spinal column share some common structural features. The vertebral body is in contact with the intervertebral discs and transfers the weight along the axis and length of the spinal column. The vertebral arch protects a portion of the spinal cord and, from it, extends the spinous process and transverse processes. These processes function by providing muscle attachment points, as well as by playing a role in the articulation with rib bones. The spinal cord passes through the vertebral foramen in each vertebra, down the length of the spinal column. (B)Transverse process.

3 Question No. 3 of 10 Instructions: (1) Read the problem statement and answer choices carefully, (2) Work the problems on paper as 3. An individual is injured in a motor vehicle accident and the x-ray reveals a fracture of the patient s second cervical vertebra. Based on this information, which of the following would be correct? Question #03 (A) The second cervical vertebra is known as the atlas. (B) There is no risk of injury to the dens projection, as it is part of the first cervical vertebra. (C) The second cervical vertebra has a process known as the dens projection that passes through a ligament opening in the atlas. (D) The second cervical vertebra plays no role in the pivot movement of the head. (E) The axis is fused with the 3 rd cervical vertebra by the age of 25. The second cervical vertebra is known as the axis. The dens projection originates at the second cervical vertebra and then passes cranially into the first cervical vertebra. C. Correct! The second cervical vertebra has a process known as the dens projection that passes through a ligament opening in the atlas. The ability of the head to pivot and rotate on the spinal column is due, in part, to the dens projection of the second cervical vertebra. The axis is fused with the atlas by adulthood. The cervical region of the spinal column contains two unique vertebrae, the Atlas C1 and the Axis C2. The occipital bone of the skull rests on and communicates with the first cervical vertebra C1. The arrangement of these first two vertebrae allows the rotation of the head on the spinal column. The Atlas C1 articulates with the occipital bone of the skull. This vertebra lacks a vertebral body, has oval articular facets, and has the largest vertebral foramen. The Axis C2 contains a dens or odontoid projection from the fusion of the first two cervical vertebrae. The dens projection passes through a ligament opening in the Atlas C1, which permits the skull to pivot relative to the rest of the spinal column. This fusion between C1 and C2 is not complete in children and, therefore, severe shaking can lead to dislocation and brain damage. (C) The second cervical vertebra has a process known as the dens projection that passes through a ligament opening in the atlas.

4 Question No. 4 of Which region of the spinal column is highlighted in the image below? Question #04 (A) The region of the spinal column with the largest vertebral bodies. (B) Thoracic region. (C) A region of the spinal column with no curve. (D) Cervical region. (E) Coccyx. A. Correct! The region of the spinal column identified in the image is the lumbar region, which contains vertebrae with the largest vertebral bodies. The thoracic region is made up of 12 vertebrae, which are adjacent to the cervical region. The spinal column region identified in the image forms an anterior curve. The cervical region is the first spinal column segment; the lumbar region is identified in the image. The coccyx is the most distal region of the spinal column; the lumbar region is identified in the image. 5 Lumbar Vertebrae There are 5 lumbar vertebrae, named L1 through L5. The lumbar have the largest vertebral body but the smallest vertebral foramen. These vertebrae, which form an anterior (lordotic) curve, are located in the small of the back and bear the most weight in the vertebral column. These vertebrae provide attachment points for lower back muscles. The true spinal cord ends at L2 in 98% of the human population. (A)The region of the spinal column with the largest vertebral bodies.

5 Question No. 5 of The sternum is part of the ribcage, which houses and protects the heart and lungs. Which of the following statements about the sternum is correct? Question #05 (A) The sternum is made up of 2 separate bones that fuse by the age of 25 years. (B) The xiphoid process is attached to the diaphragm. (C) The body of the sternum is attached to the costal cartilages from the rib pairs 1 through 10. (D) The sternum is attached through costal cartilages to all 12 pairs of ribs. (E) The xiphoid process articulates with the clavicles. The sternum is made up of 3 separate bones that fuse by the age of 25. B. Correct! The xiphoid process is attached to the diaphragm. The body of the sternum is only attached to the costal cartilages from rib pairs 2 through 10. The sternum, as a whole, is attached to the first 10 pairs of ribs. The first part of the sternum, which is the manubrium, articulates with the clavicles. The sternum is a 3-component bone that forms the anterior midline of the thoracic wall. The three components are the manubrium, body and xiphoid process. These 3 bones do not fuse until at least 25 years of age. The manubrium articulates with the clavicle bones and costal cartilages and contains a jugular notch. The body of the sternum is attached to the costal cartilages from the rib pairs 2 through 10. However, the 8th, 9th and 10th pairs of ribs are not directly attached to the sternum but rather through an attachment with the 7th pair of ribs. The xiphoid process is attached to the diaphragm and the rectus abdominis muscle. (B)The xiphoid process is attached to the diaphragm.

6 Question No. 6 of Which bone of the skull is labeled in the image below? A Question #06 (A) The basilar bone. (B) The occipital bone. (C) The sphenoid. (D) The temporal bone. (E) The sella turcica portion of the occipital bone. The letter A in the image is labelling the occipital bone. B. Correct! The letter A is labelling the occipital bone of the skull. The sphenoid bone is anterior to the occipital bone; the letter A is pointing to the occipital bone. The temporal bone is part of the floor of the skull; however, the letter A is pointing to the occipital bone. The sella turcica is part of the sphenoid. Occipital Bone The cranial vault, or fossa, houses the brain and changes in size as the skull grows. The foramen magnum is an opening in the occipital bone through which the medulla oblongata of the spinal cord passes. This is the route through which the central nervous system exits the skull and becomes the spinal cord. (B)The occipital bone.

7 Question No. 7 of The orbit of the eye is made up of a number of bones. The orbit contains the eye, muscles, vessels and ocular fat. Which of the following is correct? Question #07 (A) The bones of the eye orbit include the lacrimal bone and the temporal bone. (B) There are a total of 9 bones that make up the orbit of the eye. (C) The ethmoid bone is part of the eye orbit. (D) The bones of the eye orbit include the lacrimal bone and the parietal bone. (E) The superior orbital fissure is a fissure of the zygomatic bone. The lacrimal bone is part of the eye orbit; however, the temporal bone is not. There are a total of 7 bones that make up the eye orbit. C. Correct! The ethmoid bone is one of the 7 bones that make up the orbit of the eye. The lacrimal bone is part of the eye orbit, but the parietal bone is not. The superior orbital fissure is a foramen in the skull, which lies between the wings of the sphenoid. There are a total of seven bones that articulate to form the eye orbit. The bones are the: frontal, lacrimal, ethmoid, zygomatic, maxillary, palatine and the sphenoid. Contained within the orbit are the eyeball, ocular musculature, nerves and blood vessels. There are a number of nerves that pass through the superior orbital fissure, including: superior division of the oculomotor nerve, trochlear nerve, abducens nerve, and the sympathetic fibers from the cavernous plexus. (C) The ethmoid bone is part of the eye orbit.

8 Question No. 8 of Which of the following are examples of a diarthrosis joint? Question #08 (A) Knee joint. (B) Elbow joint. (C) Sagittal suture. (D) Both A and B are correct. (E) None of the answers are correct. The knee joint is an example of a diarthrosis joint, but this is not the only correct answer. The elbow joint is an example of a diarthrosis joint, but this is not the only correct answer. The sagittal suture is an example of a synarthrosis joint. D. Correct! Both the knee joint and the elbow joint are both examples of a diarthrosis joint. There is a correct answer option. The joints (articulations) of the body are the movement points for bones that allow such movements as bending an arm or leg. The joints of the body can be categorized into three main groups based on function: (1) synarthrosis joint, (2) amphiarthrosis, and (3) diarthrosis. This categorization is dependent on the amount of movement at the joint. An example of a synarthrosis joint is the suture joints found in between the bones of the skull. This type of joint can convert from a fibrous suture to solid mass of bone (bony fusion). An amphiarthrosis joint permits a little movement between two bones; examples include the symphysis between the pubic bones in the pelvis and fibrous connections between the tibia and fibula. A diarthrosis joint permits movement in a wide range of motion, a freely movable joint. There are many examples of these types of joints in the body: knee joint, elbow, ankle and wrist. (D)Both A and B are correct.

9 Question No. 9 of Which type of joint movement is labeled in the image below? Question #09 A (A) Plantar flexion. (B) Dorsiflexion. (C) Depression. (D) Elevation. (E) Adduction. A. Correct! The movement labeled in the image is plantar flexion. Dorsiflexion is when the heel is pushed down and the toes are raised; the movement labeled in the image is plantar flexion, the opposite movement. An example of a depression movement would be lowering the shoulders. An example of an elevation movement would be raising the shoulders, such as during a shrug. An example of an adduction movement is when the fingers are pulled in together from being spread out. Dorsiflexion Plantar Flexion There are also special joint movements that are specific to the articulation, such as depression and elevation while shrugging the shoulders. The ankle joint is capable of dorsiflexion, which is raising the toes up, and plantar flexion, which elevates the heel. Angular movements at joints include: adduction, abduction, flexion and extension. For example, when the fingers are brought together again, this is adduction. When the fingers are spread out or away from the body, this is known as abduction. These terms refer to the appendicular skeleton. (A)Plantar flexion.

10 Question No. 10 of 10 Instructions: (1) Read the problem statement and answer choices carefully, (2) Work the problems on paper as 10. The ankle joint includes the tibia bone, fibula bone and the talus bone. The ankle joint is made up of more than one actual joint. Based on this, which of the following is correct? Question #10 (A) The tibiotalar joint involves the tibia bone and the trochlea of the talus. (B) The ankle joint is actually made up of two joints: the tibiotalar and the tibiofibular joint. (C) The fibula bone does not articulate with any other bones in the ankle region. (D) There are a total of 6 joints in the ankle. (E) There are only 3 joints in the ankle region. A. Correct! The tibiotalar joint, which is one of 4 joints that make up the ankle joint, involves the tibia bone and the trochlea of the talus. The ankle joint includes the following portions: (1) tibiotalar joint, between the tibia articulation and the trochlea of the talus. This joint is the primary weight-bearing joint in the ankle, (2) proximal tibiofibular joint, (3) distal tibiofibular joint, and the (4) fibulotalar joint. The fibula bone articulates with the tibia and the talus bone. There are a total of 4 joints in the ankle region of the body. There are a total of 4 joints in the ankle region of the body. The ankle joint is a hinge diarthrosis joint made up of articulations between the tibia, fibula and talus bone. This joint permits dorsiflexion and plantar flexion of the foot. The ankle joint includes the following portions: (1) tibiotalar joint, between the tibia articulation and the trochlea of the talus. This joint is the primary weightbearing joint in the ankle, (2) proximal tibiofibular joint, (3) distal tibiofibular joint, and the (4) fibulotalar joint. A number of ligaments along the length of the tibia and the fibula hold these two bones in place. The articular capsule of the ankle extends from the distal surfaces of the tibia and the medial malleolus of the fibula and the talus bone. The medial deltoid ligament and the three lateral ligaments function to prevent the ankle bones from sliding side to side. (A)The tibiotalar joint involves the tibia bone and the trochlea of the talus.