Which of the following is INCORRECT with respect to bone and its associated part ?

Options

A. Atlas vertebra - Odontoid process
B. Pectoral girdle - Acromion process
C. Humans - Trochlea
D. Ulna - styloid process

Answer

To determine which of the following statements about bone and its associated parts is incorrect, we will analyze each option provided.

### Step-by-Step Solution:

1. **Understanding Atlas and Odontoid Process**:
- The atlas is the first cervical vertebra (C1) and supports the skull. It does not have an odontoid process.
- The odontoid process (or dens) is a bony projection on the second cervical vertebra (C2), known as the axis. It allows for the rotation of the head.
- Therefore, the statement that the atlas vertebra is associated with the odontoid process is incorrect.

2. **Pectoral Girdle and Acromion Process**:
- The pectoral girdle consists of the scapula and clavicle.
- The acromion process is a bony process on the scapula that forms the highest point of the shoulder and serves as an attachment point for muscles and ligaments.
- This association is correct.

3. **Trochlea in Humans**:
- The trochlea is a structure found in the humerus (upper arm bone) that articulates with the ulna (one of the forearm bones).
- It is not a motor neuron but rather a part of the bone structure. However, the statement may be misleading as it does not accurately describe the trochlea's function.
- This association is somewhat misleading but not entirely incorrect.

4. **Ulna and Styloid Process**:
- The ulna does have a styloid process, which is a slender projection at the distal end of the ulna.
- The styloid process serves as an attachment point for ligaments of the wrist.
- This association is correct.

### Conclusion:
- The incorrect statement is the one that associates the atlas vertebra with the odontoid process, as the odontoid process is part of the axis vertebra, not the atlas.

### Final Answer:
The incorrect statement is that the atlas vertebra is associated with the odontoid process.

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