Study Notes: Axial and Appendicular Skeletons & Cartilage Types

Lab 3: Axial Skeleton Overview

Axial Skeleton

The axial skeleton forms the central axis of the human body and provides support and protection for the brain, spinal cord, and vital organs. It consists of the skull, vertebral column, and thoracic cage.

• Skull: Protects the brain and forms the structure of the face.

• Vertebral Column: Supports the body and protects the spinal cord.

• Thoracic Cage: Includes the ribs and sternum, protecting the heart and lungs.

Fetal Skull Fontanelles are soft spots on a baby's skull where the bones have not yet fused. These allow for growth of the brain and skull during infancy.

• Anterior Fontanelle: Largest, located at the top of the skull.

• Posterior Fontanelle: Smaller, located at the back of the skull.

• Function: Allows for flexibility during birth and rapid brain growth.

Types of Cartilage

Cartilage is a flexible connective tissue found in various parts of the body. There are three main types, each with distinct properties and functions.

• Hyaline Cartilage: Most common type; provides support with some flexibility. Found in the nose, trachea, and at the ends of long bones.

• Fibrocartilage: Contains dense bundles of collagen fibers; very strong and resistant to compression. Found in intervertebral discs and pubic symphysis.

• Elastic Cartilage: Contains elastic fibers; highly flexible. Found in the external ear and epiglottis.

Examples of Locations and Functions:

• Hyaline Cartilage: Articular surfaces of bones, costal cartilages of ribs.

• Fibrocartilage: Menisci of knee, intervertebral discs.

• Elastic Cartilage: Auricle of ear, epiglottis.

Table: Comparison of Cartilage Types

Type	Main Features	Locations	Functions
Hyaline	Glassy matrix, few fibers	Ends of long bones, nose, trachea	Support, flexibility, smooth surfaces for joints
Fibrocartilage	Dense collagen fibers	Intervertebral discs, pubic symphysis	Shock absorption, strength
Elastic	Elastic fibers, flexible	External ear, epiglottis	Flexibility, shape retention

Lab 4: Appendicular Skeleton

Appendicular Skeleton

The appendicular skeleton consists of the bones of the limbs and the girdles that attach them to the axial skeleton. It is essential for movement and manipulation of the environment.

• Pectoral Girdle: Clavicle and scapula, attaching the upper limbs to the trunk.

• Upper Limbs: Humerus, radius, ulna, carpals, metacarpals, phalanges.

• Pelvic Girdle: Hip bones (ilium, ischium, pubis), attaching the lower limbs to the trunk.

• Lower Limbs: Femur, tibia, fibula, tarsals, metatarsals, phalanges.

Function: Facilitates movement, supports body weight during locomotion, and allows manipulation of objects.

Table: Major Bones of the Appendicular Skeleton

Region	Main Bones
Pectoral Girdle	Clavicle, Scapula
Upper Limb	Humerus, Radius, Ulna, Carpals, Metacarpals, Phalanges
Pelvic Girdle	Ilium, Ischium, Pubis
Lower Limb	Femur, Tibia, Fibula, Tarsals, Metatarsals, Phalanges

Practical Exam Structure

Exam Content Breakdown

The practical exam will assess knowledge of the axial and appendicular skeletons, as well as histology. Students should be able to identify bones and cartilage types, and understand their functions and locations.

• Axial Skeleton: 15 questions (11 on the skull, 4 on other axial bones)

• Appendicular Skeleton: 22 questions

• Histology: 3 questions

Preparation Tips:

• Review bone structures and locations using word lists and diagrams.

• Understand the differences between cartilage types and their functions.

• Practice identifying bones and cartilage in lab slides and models.