Skeletal System Flashcards
What are the 4 functions of the skeletal system?
- to define the shape of the body
- to form the walls of inner compartments and protect organs
- to enable posture and movements
- also involved in mineral storage and blood production
What makes up the axial skeleton?
The cranium/skull which has 22 bones (viscerocranium [14 facial bones] and neurocranium [8 bones around the brain]), the vertebral column which has 26 bones/vertebrae, and the rib cage (12 pairs) and sternum
_______ bones have a long, tube-like _______ which is strong but has some flexibility, and is mostly _______ bone. They have 2 _______ on the ends, which are the _______ ________ for joints, and are mostly ______, but are _______ on the surface. The ________ _______ _______ separates the diaphysis and epiphyses, and is the site of growth. Once growth is complete, the plate _______ to form the ____ ____. The outer surface of the bones is ________, which is the site of attachment for tendons. The ________ lines the internal surfaces of cavities within bones.
LONG have a long, tube-like DIAPHYSIS which is strong but has some flexibility, and is mostly COMPACT bone. They have 2 EPIPHYSES on the ends, which are the ARTICULAR SURFACE for joints, and are mostly SPONGY, but are COMPACT on the surface. The EPIPHYSEAL GROWTH PLATE separates the diaphysis and epiphyses, and is the site of growth. Once growth is complete, the plate OSSIFIES to form the EPIPHYSEAL LINE. The outer surface of the bones is PERIOSTEUM, which is the site of attachment for tendons. The ENDOSTEUM lines the internal surfaces of cavities within bones.
Short bones are similar in structure to what other bone type? Give 2 examples of short bones.
They are similar to long bones. Examples of short bones are the bones of the wrist and ankles.
Flat bones are _____, ______, and usually ______. Examples of flat bones are the _____, ______, _____, and ______.
Flat bones are THIN, FLAT, and usually CURVED. Examples of flat bones are the SKULL, STERNUM, SCAPULA, and RIBS.
Irregular bones are bones that don’t fit into other categories. What are 3 examples?
Vertebrae, sacrum, and facial bones.
______ bones are small, round bones embedded in _____. Their function is to_____ ______ and ______ _______. An example is the ______.
SESMOID bones are small, round bones embedded in TENDONS. Their function is to PROTECT TENDONS and INCREASE MOVEMENT . An example is the PATELLA.
_____ bones have collagen fibres ______ orientated, and are formed in foetal development or in bone repair.
WOVEN bones have collagen fibres RANDOMLY orientated, and are formed in foetal development or in bone repair.
________ break down woven bone while ______ build new bone. Bone mass decreases after 35 years old when ______ is greater than ______, resulting in osteoporosis which is when bones are _____ & ______.
OSTEOCLASTS break down woven bone while OSTEOBLASTS build new bone. Bone mass decreases after 35 years old when ABSORPTION is greater than FORMATION, resulting in osteoporosis which is when bones are WEAK & PORUS.
_____ bone is remodelled into ______ bone. ______ bones are mature bone, which have collagen fibres organised _____.
WOVEN bone is remodelled into LAMELLAR bone. LAMELLAR bones are mature bone, which have collagen fibres organised PARALLEL.
Joints are a place where 2 or more bones make contact. There are 3 structural classifications of joints: Fibrous, Cartilaginous, and Synovial – describe the 3 types.
Fibrous – bones are joined by dense fibrous connective tissue
Cartilaginous – bones are joined by cartilage
Synovial – bones are not directly joined, but have a synovial cavity and are united by an articular capsule
The general structure of the vertebrae is
• _____ – this is large, flat and disk shaped, with flat surfaces that face inferior/superior
• Pedicle – this is the ____ of the_____, on either side
• Foramen – the ____ for the ______ ______
• ______ – lateral & posterior walls of foramen
• Lamina – ________ part of arch
• Spinous processes – process where ______ join, site of ______ attachment
The general structure of the vertebrae is
• BODY – this is large, flat and disk shaped, with flat surfaces that face inferior/superior
• Pedicle – this is the FOOT of the ARCH, on either side
• Foramen – the HOLE for the SPINAL CORD
• ARCH – lateral & posterior walls of foramen
• Lamina – POSTERIOR part of arch
• Spinous processes – process where LAMINA join, site of MUSCLE attachment
Cervical vertebrae have a ____ body, and so dislocations are common. They have a______ spinous processes, and _______ ________ for vertebral artery. The first cervical vertebrae is called the _____, and it has no ______ or ________ ________ . The second cervical vertebrae is called the ______ , and it has good ______ and a _______ process to fit into atlas. The seventh cervical vertebrae has a prominent _________ _______, which can be felt at the base of the neck.
Cervical vertebrae have a SMALL body, and so dislocations are common. They have a BIFID spinous processes, and TRANSVERSE FORAMEN for vertebral artery. The first cervical vertebrae is called the ATLAS and it has no BODY or SPINOUS PROCESSES. The second cervical vertebrae is called the AXIS, and it has good ROTATION and a DENS process to fit into atlas. The seventh cervical vertebrae has a prominent SPINOUS PROCESS, which can be felt at the base of the neck.
Thoracic vertebrae have ______ processes, and joints facets for the ribs on _______ processes.
Thoracic vertebrae have LONG processes, and joints facets for the ribs on TRANSVERSE processes.
What type of body do lumbar vertebrae have? Are the processes strong or weak? Why are ruptured intervertebral disks common here?
Lumbar vertebrae have a large, thick body and strong processes. Ruptured intervertebral disks are common here due to the weight of the body.
What type of vertebrae are found in the sacrum?
The sacrum has fused vertebrae, with the transverse processes fused to form the lateral part, and spinous processes partially fused to form the sacral crest on the dorsum.
How many vertebrae make up the coccyx? What is different about these vertebrae to the general structure?
The coccyx, or tailbone, is made of 3-5 semi-fused vertebrae. They are small vertebrae, with no foramen or obvious processes. It can easily be broken if it is landed on.
What type of joints are found between vertebrae?
Zygapophyseal joints, which are planar joints that allow restricted sliding movements, and also an intervertebral disc, which is a symphysis joint.
What are the 3 functions of the intervertebral disc?
- to prevent the bodies rubbing
- to act as a shock absorber
- to enable limited movement in all directions
Intervertebral discs are made of ________. There is the external annulus fibrosus, which is a _____ ______, and the internal ________ ________, which is the core, gel-like material.
Intervertebral discs are made of FIBROCARTILAGE. There is the external annulus fibrosus, which is a FIBROUS SACK and the internal NUCLEUS PROPULSUS, which is the core, gel-like material.
What happens to intervertebral discs with age?
They weaken and compress
The _____ and ______ notches of two adjacent vertebrae form a _______ in which the spinal nerve emerges
The INFERIOR and SUPERIOR notches of two adjacent vertebrae form a FORAMEN in which the spinal nerve emerges.
What is a primary curvature of the spine?
Name the 2 primary curvatures.
The primary curvatures curve outwards (kyphosis) to create a C-shaped curve. They are present in the neonate, and are the natural embryonic outward curvature of the back.
Thoracic and sacral/coccygeal are the primary curvatures of the spine.
What is a secondary curvature of the spine?
Name the 2 secondary curvatures, and describe how they form.
The secondary curvatures curve inwards (lordosis) and develop after birth.
The cervical curve develops when the baby lifts it’s head. It is convex anteriorly and develops in the neck.
The lumbar curve is convex anteriorly and forms when the child starts to sit and walk.
