030-444 ACSM Certified Clinical Exercise Physiologist Exam

Yes, C. Most bones of the axial skeleton are of this type. is the correct answer because it is the false statement (the EXCEPT).
Explanation
The question asks for the statement that is NOT true about long bones.
Option Analysis
A. The diaphysis is composed of compact bone. ✅ True
The diaphysis is the shaft of a long bone.
It is primarily made of compact (cortical) bone, providing strength.
B. The epiphysis consists of spongy bone. ✅ True
The epiphyses are the ends of long bones.
They consist mainly of spongy (cancellous) bone covered by a thin layer of compact bone.
C. Most bones of the axial skeleton are of this type. ❌ False (Correct Answer)
The axial skeleton includes the skull, vertebral column, ribs, and sternum.
Most of these are flat, irregular, or sesamoid bones, not long bones.
Long bones are found mainly in the appendicular skeleton (arms and legs), such as the femur, humerus, tibia, and radius.
D. The central shaft encases the medullary canal. ✅ True
The diaphysis (central shaft) surrounds the medullary cavity (medullary canal), which contains bone marrow.
Exam Tip
Long Bone Structure
Diaphysis = Shaft = Compact bone
Epiphysis = Ends = Spongy bone
Medullary cavity = Inside the shaft
Long bones = Mainly in the appendicular skeleton
✅ Correct Answer: C. Most bones of the axial skeleton are of this type.

The question asks which option is a contractile protein found in skeletal muscle.
The two primary contractile proteins are:
Myosin (thick filament)
Actin (thin filament)
These proteins interact to produce muscle contraction.
Option Analysis
A. Myosin ✅ Correct
Myosin is a contractile protein.
It forms the thick filaments in muscle fibers and interacts with actin to generate force during muscle contraction.
B. Muscle fascicle ❌
A fascicle is a bundle of muscle fibers, not a protein.
C. Myofibril ❌
A myofibril is a rod-like structure inside a muscle fiber.
It contains the contractile proteins (actin and myosin), but it is not itself a protein.
D. Muscle fiber ❌
A muscle fiber is a muscle cell, not a contractile protein.
Muscle Organization (largest to smallest)
Muscle
Fascicle
Muscle fiber (cell)
Myofibril
Sarcomere
Actin & Myosin (contractile proteins)
Exam Tip
Remember:
Actin = Thin filament
Myosin = Thick filament
Both are contractile proteins responsible for muscle contraction.
✅ Correct Answer: A. Myosin.