OSTEOLOGY Flashcards
What is Osteology?
Osteology is the study of bones that make up the skeleton.
It comes from the Greek words “osteon” meaning bone and “logos” meaning study.
What are the main functions of bones?
Protection: Bones protect vital organs, like the skull protecting the brain.
Leverage and Movement: Bones act as levers for muscles, allowing movement.
Support and Shape: Bones give structure and form to the body, holding it upright.
Blood Cell Formation: Bones produce blood cells in the bone marrow.
Mineral Storage: Bones store essential minerals like calcium and phosphorus.
What are the three main divisions of the skeleton?
Axial Skeleton: Includes the skull, vertebral column (spine), ribs, and sternum. It forms the central framework of the body.
Appendicular Skeleton: Comprises the limbs, including the thoracic (front) and pelvic (hind) limbs, which are attached to the axial skeleton.
Heterotopic Skeleton: Consists of bones that are not part of the main skeleton, like the os penis (bone in the penis), os rostri (bone in the snout of some animals), and os cordis (bone in the heart of some species).
What are the different types of bones and their functions?
Long Bones: Cylindrical and longer than wide; act as levers for movement (e.g., femur, humerus).
Flat Bones: Thin and often curved; provide protection to organs (e.g., skull, scapula).
Irregular Bones: Complex shapes; involved in protection and support (e.g., vertebrae).
Sesamoid Bones: Small bones embedded within tendons; reduce friction in joints (e.g., patella).
Pneumatic Bones: Contain air spaces, making them lighter (e.g., bones in birds).
What are the main parts of a typical long bone?
Metaphysis: The flared part of the bone between the shaft (diaphysis) and the ends (epiphyses).
Epiphysial Cartilage (Physis): The growth plate where new bone is formed.
Periosteum: A dense connective tissue covering the bone’s surface, involved in growth and repair.
Endosteum: Thin membrane lining the inside of the bone’s marrow cavity, involved in growth and repair.
Articular Cartilage: Smooth tissue covering the ends of bones at joints to reduce friction.
What are some examples of articular projections on bones?
Head: A rounded, spherical projection, often found at the end of long bones (e.g., head of the femur).
Condyle: A cylindrical, rounded mass at the end of some bones (e.g., condyles at the distal end of the femur).
Trochlea: A pulley-like structure (e.g., trochlea at the distal end of the humerus).
Facet: A small, flat surface on a bone, often where two bones meet (e.g., facets between carpal bones).
What is the difference between cranial and facial bones?
Cranial Bones: Surround and protect the brain, forming the cranium (e.g., occipital bone, frontal bone).
Facial Bones: Form the face, support sensory organs, and provide openings for air and food (e.g., maxilla, nasal bones).
What is the vertebral formula for a dog?
The vertebral formula for a dog is C7 T13 L7 S3 Cd20-23, meaning:
7 cervical (neck) vertebrae
13 thoracic (chest) vertebrae
7 lumbar (lower back) vertebrae
3 sacral (pelvic area) vertebrae
20-23 caudal (tail) vertebrae
What are the regions of the forelimb?
Pectoral Girdle: Includes the clavicle (collarbone) and scapula (shoulder blade).
Brachium: The upper arm, primarily the humerus bone.
Antebrachium: The forearm, consisting of the radius and ulna bones.
Manus: The “hand” region, including the carpus (wrist), metacarpus (bones of the hand), and digits (fingers).
What bones form the pelvic girdle?
Ilium: The large, wing-like part of the pelvis.
Ischium: The lower, back part of the pelvis.
Pubis: The front part of the pelvis.
Acetabular Bone: A small bone that forms the acetabulum (hip joint socket) with the other three bones.
