The weight of upper limb is transmitted to the axial skeleton by-
π‘ Explanation
Okay, let's tackle this question about how the upper limb's weight is transmitted to the axial skeleton. Hmm, I remember that the axial skeleton includes the skull, vertebral column, ribcage, and sternum. The upper limb is connected to the axial skeleton through the pectoral girdle, right? The pectoral girdle consists of the clavicle and scapula. The clavicle is a long bone that connects the sternum to the acromion of the scapula. So, the clavicle is part of the axial skeleton? Wait, no, the clavicle is part of the appendicular skeleton, but it connects to the axial skeleton via the sternoclavicular joint. The scapula is also part of the appendicular skeleton but is connected via the acromioclavicular joint to the clavicle. So, the main points of attachment are the sternoclavicular and acromioclavicular joints. But the question is about the transmission of weight. When the upper limb is used, the force is transmitted through the clavicle to the sternum. For example, when you lift something heavy with your arm, the force goes through the clavicle to the sternum. Also, the scapula is connected to the thoracic vertebrae by muscles, but not directly. So the main structure transmitting weight would be the clavicle. Let me check the options again. The correct answer is probably the clavicle. The sternoclavicular joint is the key point here. So the weight is transmitted via the clavicle to the sternum. Therefore, the correct answer should be the clavicle. The other options might be incorrect because they don't directly transmit the weight. For example, the scapula isn't directly connected to the axial skeleton except via the clavicle. The acromioclavicular joint is between the scapula and clavicle, but the clavicle is the main link to the sternum. So the answer is clavicle. Now, the options might have the clavicle as option C or D. Let me make sure. The core concept here is the anatomical connection between the upper limb and axial skeleton. The key structures are the clavicle and the sternoclavicular joint. The clavicle acts as a strut, transmitting forces from the upper limb to the axial skeleton. Without the clavicle, the scapula would be more mobile but less stable. So, the correct answer is the clavicle.
**Core Concept**
The upper limb's weight is transmitted to the axial skeleton via the pectoral girdle, specifically the **clavicle** and its articulation with the **sternum** (sternoclavicular joint). The clavicle acts as a rigid strut, transferring forces from the upper limb to the axial skeleton, ensuring stability while allowing shoulder mobility.
**Why the Correct Answer is Right**
The **clavicle** is the sole bony structure connecting the appendicular skeleton (upper limb) to the axial skeleton. It articulates with the **manubrium of the sternum** at the sternoclavicular joint and the **acromion of the scapula** at the acromioclavicular joint. When weight is applied to the upper limb
β Correct Answer: A. Coracoclavicular ligament