Podcast
Questions and Answers
The human skeletal system consists of approximately ______ bones in adults.
The human skeletal system consists of approximately ______ bones in adults.
206
Ligaments serve to connect ______ to ______.
Ligaments serve to connect ______ to ______.
bone, bone
The primary function of the skeleton is to provide ______ for the body.
The primary function of the skeleton is to provide ______ for the body.
support
Compact bone can withstand ______ and provides support and protection.
Compact bone can withstand ______ and provides support and protection.
The production of blood cells is known as ______.
The production of blood cells is known as ______.
Sinuses help to lighten the ______ and amplify the voice.
Sinuses help to lighten the ______ and amplify the voice.
The rib cage provides protection to the ______ and ______.
The rib cage provides protection to the ______ and ______.
The skeletal system serves as a reserve of ______ salts.
The skeletal system serves as a reserve of ______ salts.
Ossification begins about ______ weeks after fertilization.
Ossification begins about ______ weeks after fertilization.
Vitamin ______ is vital for calcium metabolism.
Vitamin ______ is vital for calcium metabolism.
In adults, about ______% of bone is remodeled every year.
In adults, about ______% of bone is remodeled every year.
Intramembranous ossification forms the flat bones of the ______.
Intramembranous ossification forms the flat bones of the ______.
Endochondral ossification involves the replacement of ______ cartilage.
Endochondral ossification involves the replacement of ______ cartilage.
Cells of the periosteum develop into ______ that produce additional bony matrix.
Cells of the periosteum develop into ______ that produce additional bony matrix.
A thin layer of epiphyseal cartilage remains, separating ______ and diaphysis.
A thin layer of epiphyseal cartilage remains, separating ______ and diaphysis.
Bone loss can occur if a person is on crutches for several ______.
Bone loss can occur if a person is on crutches for several ______.
The ______ skeleton forms the longitudinal axis of the body and contains 80 bones.
The ______ skeleton forms the longitudinal axis of the body and contains 80 bones.
The ______ skeleton contains 126 bones and forms the limbs and attachment sites.
The ______ skeleton contains 126 bones and forms the limbs and attachment sites.
The male pelvis is characterized by a narrower and less flared shape, with a pelvic inlet that is ______ or heart-shaped.
The male pelvis is characterized by a narrower and less flared shape, with a pelvic inlet that is ______ or heart-shaped.
Adult female pelvises usually exhibit a round pelvic inlet and a pubic arch angle that is greater than ______ degrees.
Adult female pelvises usually exhibit a round pelvic inlet and a pubic arch angle that is greater than ______ degrees.
Joints occur where two bones ______.
Joints occur where two bones ______.
The primary functions of joints include holding bones together, bearing weight, and allowing for ______.
The primary functions of joints include holding bones together, bearing weight, and allowing for ______.
Synarthrosis joints are characterized as ______ and consist of bones joined by fibrous tissue.
Synarthrosis joints are characterized as ______ and consist of bones joined by fibrous tissue.
Osteoclasts erode some of the inner surface of the ______ cavity, leading to an increase in size.
Osteoclasts erode some of the inner surface of the ______ cavity, leading to an increase in size.
The sutures of the skull are classified as ______ joints.
The sutures of the skull are classified as ______ joints.
At birth, the skull has fontanelles, which allow for movement during the ______ canal.
At birth, the skull has fontanelles, which allow for movement during the ______ canal.
The large anterior fontanelle typically closes by ______ years of age.
The large anterior fontanelle typically closes by ______ years of age.
The posterior fontanelle usually closes by ______ months of age.
The posterior fontanelle usually closes by ______ months of age.
Amphiarthrosis refers to joints that are ______ movable.
Amphiarthrosis refers to joints that are ______ movable.
Diarthrosis joints are classified as ______ movable joints.
Diarthrosis joints are classified as ______ movable joints.
The hinge joint allows for ______ movement.
The hinge joint allows for ______ movement.
The ellipsoidal joint permits movement both back and forth and side to ______.
The ellipsoidal joint permits movement both back and forth and side to ______.
The ______ is the shaft of the bone, where the medullary cavity is located.
The ______ is the shaft of the bone, where the medullary cavity is located.
The end of the bone is known as the ______.
The end of the bone is known as the ______.
The thin layer of cartilage that decreases friction at joints is called ______.
The thin layer of cartilage that decreases friction at joints is called ______.
The ______ lines the marrow cavity and is active during bone growth and remodeling.
The ______ lines the marrow cavity and is active during bone growth and remodeling.
The ______ is where red blood cells are produced and is found in the medullary cavity of children.
The ______ is where red blood cells are produced and is found in the medullary cavity of children.
Osteoblasts are also known as the ______ because they produce new bone.
Osteoblasts are also known as the ______ because they produce new bone.
The giant cells that dissolve bony matrix are called ______.
The giant cells that dissolve bony matrix are called ______.
The most abundant cells in bone, which assist in recycling calcium salts, are called ______.
The most abundant cells in bone, which assist in recycling calcium salts, are called ______.
Flashcards are hidden until you start studying
Study Notes
Skeletal System Overview
- Skeleton comprises about 20% of body mass.
- Adults have 206 bones; infants have about 270 bones which fuse into 206.
- Ligaments connect bone to bone, while cartilage reduces friction at joints.
Functions of the Skeletal System
- Support: Provides structural framework for the body and attachment for tissues.
- Storage: Serves as a reserve for calcium salts and lipids stored in yellow marrow.
- Blood Cell Production: Known as hematopoiesis, occurs in red marrow producing red and white blood cells, and platelets.
- Protection: Bones protect vital organs (e.g., pelvis protects reproductive organs, ribs protect heart/lungs, skull protects the brain).
- Leverage: Involved in changing magnitude and direction of muscle forces.
Bone Structure and Histology
- Types of Bone Tissue:
- Compact bone offers strength, support, and protection.
- Spongy bone (cancellous) contains a network of rods making skeleton lighter.
- Bone Components:
- Diaphysis (shaft) contains compact bone; epiphysis (ends) contains spongy bone.
- Periosteum covers outer surface; endosteum lines marrow cavity.
- Medullary cavity holds bone marrow, yellow in adults and red in children.
Cells in Bone
- Osteoblasts: Bone builders that produce new bone matrix and promote calcium deposition.
- Osteoclasts: Giant cells responsible for bone resorption and releasing minerals.
- Osteocytes: Mature bone cells that recycle calcium salts and assist in repairs.
Bone Development and Growth
- Ossification: Process of bone formation begins around 6 weeks post-fertilization and concludes around age 25.
- Requirements for Growth: Needs minerals (especially calcium), vitamins D, A, C, and various hormones for proper development.
- Bone Remodeling: About 18% of bone structure is remodeled yearly to adapt to stresses; exercise strengthens bones while inactivity can weaken them.
Types of Ossification
- Intramembranous Ossification: Bone develops from fibrous membranes, forming flat bones of the skull and clavicle.
- Endochondral Ossification: Bone replaces hyaline cartilage, primarily responsible for forming most bones.
Axial and Appendicular Skeletons
- Axial Skeleton: Comprises 80 bones along body’s longitudinal axis, supports/protects organs (includes skull, vertebrae, ribs).
- Appendicular Skeleton: Contains 126 bones forming limbs and their attachments, including pectoral and pelvic girdles.
Male vs. Female Pelvis
- Male pelvis is narrower with an oval or heart-shaped inlet; pubic arch angle is less than 90 degrees.
- Female pelvis is broader with a round inlet; pubic arch angle is greater than 90 degrees.
Articular System (Joints)
- Joints are articulations where two bones meet, aiding in stability and mobility.
- Types of Joints:
- Synarthrosis: Immovable fibrous joints (e.g., skull sutures).
- Amphiarthrosis: Slightly movable cartilaginous joints (e.g., pubic symphysis).
- Diarthrosis: Freely movable synovial joints (e.g., knee, elbow).
Types of Joint Movements
- Gliding Joints: Allow sliding movements (e.g., carpal bones).
- Hinge Joints: Permit back and forth motion (e.g., elbows, knees).
- Pivot Joints: Enable rotation (e.g., between first two cervical vertebrae).
- Condoid Joints: Allow movement in two directions (e.g., wrist joints).
Aging and the Skeletal System
- Aging affects bone density and strength, potentially leading to conditions like osteoporosis.
- Regular exercise can mitigate some impacts of aging on the skeletal system.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
