Overview of the Mandible A comparative study of the lower jaw or mandible in vertebrates explores the evolutionary adaptations, structural variations, and functional modifications of this critical skeletal element across different vertebrate groups. Here's an overview of key aspects to consider: The mandible, or lower jaw, is a key element…
JAW SUSPENSIONS IN VERTEBRATES Jaw suspension means attachment of the lower jaw with the upper jaw or the skull for efficient biting and chewing. There are different ways in which these attachments are attained depending upon the modifications in visceral arches in vertebrates. The vertebrate skull has three major parts…
Skull Bones of Scoliodon Skull Bones are consists of Cranium and sense capsules Visceral skeleton. Comments 1. Cranium and sense capsules Made up of a single piece of cartilage and divisible into 4 regions. Occipital region : Posterior-most part having a median opening, the foramen magnum. Lateral sides contain occipital…
Comparative study of Vertebral Column Scoliodon : Vertebral Column Comments : It Scoliodo Vertebral Column of 130 vertebrae divided into trunk and caudal regions. Vertebrae are amphicoelous. Trunk vertebra : It consists of neural spine, neural canal, neural arch, passage for notochord and transverse processes a ventral, thick, cylindrical centrum,…
Comparative study of Pelvic Girdles of vertebrate Scoliodon Pectoral Girdle and Fins Comments Pectoral girdle V-shaped structure made up of right and left halves united mid-ventrally. Each half is made up of coracoid portion, scapular portion and suprascapular portion. Pectoral girdle is embedded in lateral and ventral body wall posterior…
Comparative study of Pelvic Girdles of vertebrate Scoliodon Pelvic Girdle and Fins Comments Pelvic girdle : Made up of a simple flattened and transverse cartilaginous rod called ischiopubic bar, having a small blunt iliac process on either side projecting above the acetabular facet for articulation of the basal cartilage of…
Comparative study of Forelimb bones of vertebrate Forelimb Bones of Frog Forelimb Bones of Frog are Humerus, radio-ulna and hand bones constitute bones of forelimb. Comments : Humerus It is a short, cylindrical and slightly curved bone of upper arm. Proximal end fits into glenoid cavity of pectoral girdle. It…
Comparative study of Hind limb bones of vertebrate Hind Limb Bones of Frog Hind limb constitute the femur, tibio-fibula, astragalus-calcaneum and bones of foot. Comments Femur It is thigh bone having expanded ends, covered with calcified cartilages. Proximal end or head articulates with acetabulum while distal end with tibio-fibula. Tibio-fibula…