Question

Indicate whether the statement is true (T) or false (F). The pectoral girdle is specialized for weight-bearing, while the pelvic girdle is specialized for flexibility of movement. _________

Short answer

F

Step-by-step solution

Pectoral Girdle Functions

The pectoral girdle consists of the clavicle and scapula and connects the upper limb (arm) to the axial skeleton (trunk). Its main functions include providing support and allowing for various movements of the upper limb. Step 2: Analyze the pelvic girdle

Pelvic Girdle Functions

The pelvic girdle is formed by the fusion of the ilium, ischium, and pubis bones and forms the base of the spine. The pelvic girdle connects the lower limb (leg) to the axial skeleton and provides support, stability, and movement for the lower limbs. Step 3: Compare the functions of the pectoral and pelvic girdles

Comparison of Functions

From the analysis of the functions of the pectoral and pelvic girdles, it can be seen that the pectoral girdle, connecting the upper limb to the axial skeleton, allows for a wide range of movements and flexibility, while the pelvic girdle, connecting the lower limb to the axial skeleton, is more specialized for weight-bearing and stability. Step 4: Determine the validity of the statement

Statement Assessment

The statement "The pectoral girdle is specialized for weight-bearing, while the pelvic girdle is specialized for flexibility of movement" is incorrect. It should be the other way around. The pectoral girdle is specialized for flexibility of movement, while the pelvic girdle is specialized for weight-bearing. Therefore, the statement is False (F).

Key concepts

Pectoral Girdle

The pectoral girdle, also known as the shoulder girdle, comprises two main bones: the clavicle (collarbone) and the scapula (shoulder blade). This structure plays a crucial role in connecting the arms to the core part of the body, the axial skeleton. The primary function of the pectoral girdle is to provide the upper limb with a wide range of motion. This flexibility supports several daily actions, such as lifting, throwing, and rotating the arm.
Furthermore, the pectoral girdle allows for the elevation, depression, and retraction movements of the shoulder, making it integral to the dexterity and versatility of arm movements.
Unlike the pelvic girdle, which is adapted for stability and weight-bearing, the pectoral girdle prioritizes movement.

Pelvic Girdle

The pelvic girdle forms a robust base of the skeleton, consisting of the fused bones: ilium, ischium, and pubis. Unlike the agile pectoral girdle, the pelvic girdle is specifically engineered for weight-bearing. It supports the body's upper weight and transmits it to the legs.
This girdle links the lower limbs to the axial skeleton and provides stability necessary for standing and walking. It also offers support to internal organs within the pelvic region.
The stability provided by the pelvic girdle allows humans to maintain an upright posture and perform energy-intensive activities such as running and jumping.

Axial Skeleton

The axial skeleton forms the central axis of the human body and includes the skull, spinal column, and rib cage. This framework is essential for supporting the body and protecting the central nervous systems along with critical organs such as the heart and lungs.
One of its main functions is to serve as the central structure to which the pectoral and pelvic girdles attach.
This alignment provides a sturdy framework for movement and keeps the upper and lower limbs correctly positioned. The axial skeleton is thus pivotal in supporting body weight and facilitating upright posture.

Upper Limb

The upper limb consists of the arm (humerus), forearm (ulna and radius), and hand (carpals, metacarpals, and phalanges). Its connection to the axial skeleton through the pectoral girdle allows for a wide range of movements.
This flexibility is vital for tasks that require precision and dexterity, such as writing, grasping objects, and manipulating tools.
The upper limb's design includes a complex system of muscles and joints that enable rotational motions as well as the strength required for lifting and pulling objects.

Lower Limb

The lower limb includes the thigh (femur), leg (tibia and fibula), and foot (tarsals, metatarsals, and phalanges). These bones are connected to the axial skeleton via the pelvic girdle.
The lower limb is primarily designed for supporting the body's weight, allowing for balance, movement, and mobility. It facilitates activities like standing, walking, and running.
Moreover, the joints and muscles of the lower limb combine stability with strength, allowing humans to carry out physically demanding activities while maintaining body support.