BIO 141 Chapter 8

Briefly describe the two conditions that might result from incomplete fusion of the upper jaw components during embryonic development.

A *cleft lip* is the split upper lip extending from the mouth to one side of the nostril. A *cleft palate* is a congenital tissue in the midline of the palate.

List the major bones that make up the appendicular skeleton.

Pectoral girdle, upper limbs, pelvic girdle, lower limbs.

Describe the functions of the vertebral column.

Provides vertical support for the body and supports the weight of the head. It helps maintain the upright position. Most important, it houses and protects the spinal cord.

List the major bones that make up the axial skeleton.

Skull, vertebrae, sternum, coccyx.

Briefly state the function of the arches of the foot.

The arches support the weight of the body and ensures the the blood vessels and nerves on the sole of the foot are not pinched when a person is standing.

Name the joint and the bones that make up this joint that permit us to shake our heads to signify 'no'.

The articulation between the atlas and the axis called the atlantoaxial joint.

Name the joint and the bones that make up this joint that permit us to nod our heads to signify 'yes'.

The articulation between the occipital condyles and the atlas called the atlanto-occipital joint.

Explain why the ischial tuberosities of the ischium are sometimes referred to as 'sitz bones' by some health professionals.

These bones support the weight of the body when seated.

Name the vertebral structure that serves as an exit for the spinal nerves.

Intervertebral foramina.

Briefly explain what forms the perineum, an important body region in females for labor and delivery.

It is formed by muscles and skin. It is important in females as the opening must be wide enough to accommodate the fetal head during childbirth.

Briefly describe the three main spinal curvature abnormalities.

Kyphosis is an exaggerated thoracic curvature. Lordosis is an exaggerated lumbar curvature. Scoliosis is the most common; it is an abnormal lateral conformity.

State the specific type of spinal curvature abnormality seen in a pregnant woman.

Lordosis.

Explain what is meant by herniated disc.

Occurs when the gelatinous nucleus pulposus protrudes through or into the anulus fibrosus. This herniation produces a bulging of the disc contents posterolaterally into the vertebral canal and pinches the spinal cord.

Name the two structures that make up the intervertebral disc.

An outer ring of fibrocartilage called the annulus fibrosus and an inner gelatinous circular region called the nucleus pulposus.

Explain why the humerus has a region called the 'surgical neck'.

Because it is a common fracture site.

Name the vertebral structure that contains the spinal cord.

Vertebral canal.

Briefly explain the condition of sciatica.

When the herniated disc starts to pinch nerve roots and the patient feels pain down the entire lower limb.