Lab Questions Section 3 – Skeletal Anatomy and Structure of Bones and Bones of the Head and Neck
This section contains questions from the course material related to the skeletal anatomy and bone structure. Each question is answered with explanations for all answer choices, highlighting why the correct choice is accurate and why the others are incorrect, unless otherwise noted. Additionally, labeling of bone components is included where applicable.
1. Which bone cells are entrapped in the bone matrix?
Choice
Explanation
a. Osteoclast cells
Incorrect. Osteoclasts are large, multinucleated cells involved in bone resorption but are not entrapped in the matrix. They break down old or damaged bone tissue.
b. Osteogenic cells
Incorrect. These are undifferentiated precursor cells found in the periosteum and endosteum that differentiate into osteoblasts but are not embedded in the matrix.
c. Osteoblast cells
Incorrect. Osteoblasts build bone matrix but are not embedded in it; they eventually become osteocytes.
d. Osteocyte cells
Correct. Osteocytes are mature bone cells that are entrapped within the bone matrix. They originate from osteoblasts that become trapped after secreting the bone matrix.
2-5. Label the components of the bone matrix (No explanation needed):
Label
Name
A
Spongy Bone
B
Bone Marrow
C
Compact Bone
D
Periosteum
6. Which statement about the diaphysis labeled D is true?
Choice
Explanation
a. The diaphysis is comprised of compact bone and cartilage.
Incorrect. The diaphysis consists primarily of compact bone. Cartilage is typically located at the bone ends (epiphyses), not within the diaphysis.
b. The diaphysis is mostly compact bone.
Correct. The diaphysis mainly consists of dense, strong compact bone; cartilage is not part of the diaphysis but rather in growth plates.
c. The diaphysis is comprised of spongy bone and cartilage.
Incorrect. Spongy bone is found primarily in the epiphyses, not in the diaphysis, and cartilage is not present within the diaphysis.
d. The diaphysis is mostly spongy bone.
Incorrect. Spongy bone is located in the epiphyses; the diaphysis contains compact bone for strength and support.
7. Which image is classified as an irregular shaped bone?
Choice
Explanation
a. A – Long bones
Incorrect. Long bones are longer than they are wide and function as levers, such as the femur.
b. B – Sesamoid bones
Incorrect. Sesamoid bones are small bones embedded within tendons, like the patella.
c. C – Flat bones
Incorrect. Flat bones are thin and broad, consisting of two compact bone layers with spongy bone in between.
d. D – Irregular bones
Correct. Irregular bones have complex shapes, such as vertebrae, sphenoid, and ethmoid bones.
8. Which type of bone is labeled A?
Choice
Explanation
a. Irregular bones
Incorrect. Irregular bones have complex shapes and are not typically cylindrical.
b. Short bones
Incorrect. Short bones are roughly equal in length and width, like carpals, not long and cylindrical.
c. Long bones
Correct. Long bones have a long shaft with expanded ends, mainly composed of compact bone, acting as levers.
d. Flat bones
Incorrect. Flat bones are thin and broad, unlike the labeled bone A.
9. Bones that surround the spinal cord are classified as ________ bones.
Choice
Explanation
a. Flat
Incorrect. Flat bones protect organs like the skull and ribs but do not surround the spinal cord.
b. Irregular
Correct. Vertebrae surrounding the spinal cord are irregular bones due to their complex shapes.
c. Short
Incorrect. Short bones are small and cube-like, such as carpals, not surrounding the spinal cord.
d. Sesamoid
Incorrect. Sesamoid bones form within tendons, not around the spinal cord.
10. What is the classification of bones labeled A and B?
D312 Lab Week 2 – Comparative Study of Prokaryotic and Eukaryotic Cells
Choice
Explanation
a. Long bones
Correct. Includes humerus, radius, ulna, femur, etc., which are characterized by their length and structure.
b. Flat bones
Incorrect. Flat bones include skull bones, ribs, and scapula but not bones labeled A and B in this image.
c. Irregular bones
Incorrect. Irregular bones have unique shapes like vertebrae, not represented by A and B.
d. Short bones
Incorrect. Short bones include carpals and tarsals, not A and B in this context.
11. What is part of the axial skeleton?
Choice
Explanation
a. Thigh bones
Incorrect. Thigh bones (femur) belong to the appendicular skeleton (limbs).
b. Vertebral column
Correct. The axial skeleton consists of the skull, vertebral column, and thoracic cage.
c. Foot bones
Incorrect. Foot bones are part of the appendicular skeleton.
d. Shoulder bones
Incorrect. Shoulder bones belong to the appendicular skeleton.
12. The appendicular skeleton ________.
Choice
Explanation
a. forms the vertical axis of the body
Incorrect. The axial skeleton forms the vertical axis, not the appendicular.
b. includes all bones of the body trunk and limbs
Incorrect. The trunk bones belong to the axial skeleton; appendicular includes limbs only.
c. consists of 126 bones
Correct. The appendicular skeleton includes 126 bones of the upper and lower limbs.
d. is comprised of the bones of the lower and upper limbs
Correct, but since c is more specific with bone count, c is the best choice here.
References
Marieb, E. N., & Hoehn, K. (2019). Human Anatomy & Physiology (11th ed.). Pearson. Tortora, G. J., & Derrickson, B. (2017). Principles of Anatomy and Physiology (15th ed.). Wiley. Kumar, V., Abbas, A. K., & Aster, J. C. (2020). Robbins Basic Pathology (10th ed.). Elsevier.
