Week 30 / Muscle, Joints & Bones -4 Flashcards
🧠 Question 1: What are the two fundamental functions of joints (articulations)?
✅ Answer:
1. Provide for skeletal mobility.
2. Hold the skeleton together.
🧠 Question 2: Why are joints considered the weakest parts of the skeleton?
✅ Answer: Joints are the weakest parts of the skeleton because they are the sites where two or more bones meet, but they have a remarkable ability to resist forces that could tear them apart.
🧠 Question 1: What is the focus of functional classification of joints?
✅ Answer: The functional classification of joints focuses on the amount of movement.
🧠 Question 2: What are the three types of functional joint classifications?
✅ Answer:
Synarthroses (immovable joints)
Amphiarthroses (slightly movable joints)
Diarthroses (freely movable joints)
🧠 Question 3: What is the focus of structural classification of joints?
✅ Answer: The structural classification of joints is based on the material binding them and the presence or absence of a joint cavity.
🧠 Question 4: What are the four types of structural joint classifications?
✅ Answer:
Fibrous
Cartilaginous
Synovial
🧠 Question 1: What are the three types of fibrous joints?
✅ Answer:
Suture
Syndesmoses
Gomphoses
🧠 Question 3: What are the six types of synovial joints?
✅ Answer:
Gliding
Hinge
Pivot
Condyloid
Saddle
Ball and socket
🧠 Question 2: What are the two types of cartilaginous joints?
✅ Answer:
Synchondroses
Symphyses
🧠 Question 1: How are bones joined in fibrous joints?
✅ Answer: Bones are joined by fibrous tissue; no joint cavity is present.
🧠 Question 2: What are the three types of fibrous joints?
✅ Answer:
Sutures
Syndesmosis
Gomphosis
🧠 Question 3: What characterizes a suture fibrous joint?
✅ Answer: Dense fibrous connective tissue.
🧠 Question 4: What is a syndesmosis fibrous joint?
✅ Answer: A cord or band of connective tissue that connects bones.
🧠 Question 5: What is a gomphosis fibrous joint?
✅ Answer: A peg-in-socket arrangement surrounded by fibrous tissue or periodontal ligament.
🧠 Question 1: Where do sutures occur?
✅ Answer: Only between bones of the skull.
🧠 Question 2: How do the bones in sutures articulate?
✅ Answer: Wavy articulating bone edges interlock.
🧠 Question 3: What fills the junction of sutures?
✅ Answer: Connective tissue.
🧠 Question 4: What is the function of sutures?
✅ Answer: Rigid splices bind bones of the skull together tightly.
🧠 Question 1: How are the bones connected in syndesmoses?
✅ Answer: The bones are connected exclusively by ligaments, cords, or bands of fibrous tissue.
🧠 Question 2: What type of fibrous tissue occurs in syndesmoses?
✅ Answer: Longer fibrous tissue occurs as a sheet or membrane.
🧠 Question 3: What does the longer fibrous tissue in syndesmoses permit?
✅ Answer: It permits the joint to “give” or flex.
🧠 Question 1: What is the structure of a gomphosis joint?
✅ Answer: It is a “peg-in-socket” joint.
🧠 Question 2: What is the only example of a gomphosis joint?
✅ Answer: The articulation of a tooth with its bony alveolar socket.
🧠 Question 3: What ligament is associated with a gomphosis joint?
✅ Answer: The short periodontal ligament.
🧠 Question 1: What unites the articulating bones in cartilaginous joints?
✅ Answer: Cartilage.
🧠 Question 2: Do cartilaginous joints have a joint cavity?
✅ Answer: No, they lack a joint cavity.
🧠 Question 3: How movable are cartilaginous joints?
✅ Answer: They are not highly movable.
🧠 Question 4: What are the two types of cartilaginous joints?
✅ Answer: Synchondroses and symphyses.
🧠 Question 1: What type of cartilage unites the bones in synchondroses?
✅ Answer: Hyaline cartilage.
🧠 Question 2: Are synchondroses movable or immovable joints?
✅ Answer: Immovable (synarthroses).
🧠 Question 3: Give two examples of synchondroses.
✅ Answer: Epiphyseal plates and the joint between the first rib’s costal cartilage and the manubrium of the sternum.
🧠 Question 1: What type of cartilage unites the bones in symphyses?
✅ Answer: Fibrocartilage.
🧠 Question 2: Are symphyses movable or immovable joints?
✅ Answer: Slightly movable (amphiarthroses).
🧠 Question 3: What is the role of hyaline cartilage in symphyses?
✅ Answer: It covers the articular surfaces of bones to reduce friction.
🧠 Question 4: Give two examples of symphyses.
✅ Answer: Intervertebral discs and the pubic symphysis of the pelvis.
🧠 Question 1: What type of joint are synovial joints?
✅ Answer: Diarthroses (freely movable).
🧠 Question 2: What is a key characteristic of synovial joints?
✅ Answer: They contain a fluid-filled joint cavity.
🧠 Question 1: What type of cartilage is found in synovial joints?
✅ Answer: Hyaline cartilage.
🧠 Question 3: Are synovial joints the most common joints in the body?
✅ Answer: Yes, synovial joints include most of the body’s joints.
🧠 Question 3: What is the joint (synovial) cavity?
✅ Answer: It is a potential space filled with a small amount of synovial fluid.
🧠 Question 2: What is the function of articular cartilage in synovial joints?
✅ Answer: It cushions compression and protects the ends of bones from being crushed.
🧠 Question 1: What are the two layers of the articular (or joint) capsule in synovial joints?
✅ Answer:
Outer: fibrous capsule of dense irregular connective tissue.
Inner: synovial membrane of loose connective tissue.
🧠 Question 2: What is the function of the synovial membrane in the articular capsule?
✅ Answer: It makes synovial fluid.
🧠 Question 1: What is synovial fluid a filtrate of?
✅ Answer: Blood.
🧠 Question 3: What does the articular capsule line in synovial joints?
✅ Answer: It lines all internal joint surfaces not covered by cartilage.
🧠 Question 2: What special components does synovial fluid contain?
✅ Answer: Special glycoproteins.
🧠 Question 4: What is “weeping lubrication” in synovial joints?
✅ Answer: It is the process where synovial fluid is squeezed into and out of the cartilage, nourishing the cells.
🧠 Question 2: Where are capsular (intrinsic) ligaments located?
✅ Answer: They are part of the fibrous capsule.
🧠 Question 3: What are the functions of synovial fluid?
✅ Answer:
Nourishes cartilage.
Functions as a slippery lubricant.
🧠 Question 1: What are the three possible types of reinforcing ligaments in synovial joints?
✅ Answer:
Capsular (intrinsic)
Extracapsular
Intracapsular
🧠 Question 3: Where are extracapsular ligaments located?
✅ Answer: They are located outside the capsule.
🧠 Question 4: Where are intracapsular ligaments located?
✅ Answer: They are deep to the capsule and covered by the synovial membrane.
🧠 Question 1: What is the function of nerves in synovial joints?
✅ Answer:
Detect pain
Monitor stretch (helps sense posture and body movements)
🧠 Question 2: What is the function of blood vessels in synovial joints?
✅ Answer:
Provide a rich blood supply
Have extensive capillary beds in the synovial membrane that produce the blood filtrate
🧠 Question 2: In which joints can you find an articular disc or meniscus?
✅ Answer:
Knee
Temporomandibular joint (TMJ)
🧠 Question 1: What is an articular disc or meniscus in joints?
✅ Answer:
A crescent-shaped structure found in some joints where bone ends have different shapes or fit poorly.
Helps allow two kinds of movement, such as in the jaw.
Examples: Knee, Temporomandibular joint (TMJ).
🧠 Question 1: What are bursae and what is their function?
✅ Answer:
Contain synovial fluid.
Not joints but often associated with them.
Act like ball bearings to reduce friction.
Flattened sacs lined by synovial membrane.
Located where ligaments, muscles, tendons, or bones rub together.
🧠 Question 2: What is a tendon sheath and where is it found?
✅ Answer:
A tendon sheath is similar to a bursa but is specifically found around tendons subjected to friction.
🧠 Question 1: How do articular surfaces influence joint stability?
✅ Answer:
Articular surfaces play a minor role in joint stability.
Some deep sockets or grooves, however, provide more stability.
🧠 Question 2: How do ligaments affect joint stability?
✅ Answer:
More ligaments usually make a joint stronger.
Ligaments can stretch only 6% beyond their normal length before they tear.
Once stretched, ligaments stay stretched.
🧠 Question 3: What role does muscle tone play in joint stability?
✅ Answer:
Muscle tone refers to the constant, low level of contractile force.
It keeps tension on the ligaments.
Muscle tone is especially important in the shoulders, knees, and arches of the foot.
🧠 Question 1: What type of movement does gliding allow in synovial joints?
✅ Answer:
Gliding allows one bone to slide over another, typically occurring in flat joints.
🧠 Question 2: What are the types of angular movements allowed by synovial joints?
✅ Answer:
Flexion: Decreases the angle between two bones.
Extension: Increases the angle between two bones.
Abduction: Moves a bone away from the midline of the body.
Adduction: Moves a bone toward the midline of the body.
Circumduction: A circular movement of a limb or finger.
🧠 Question 3: What movement is described by rotation in synovial joints?
✅ Answer:
Rotation involves the turning of a bone around its own axis.
🧠 Question 4: What are special movements in synovial joints?
✅ Answer:
Special movements are unique or less common joint movements, such as elevation, depression, pronation, supination, inversion, eversion, protraction, retraction, and opposition.
🧠 Question 1: What is gliding in joint movements?
✅ Answer:
Gliding is when one flat bone surface glides or slips over another similar surface.
What are special the movements made by joints?
Special movements
* Pronation
* Supination
* Dorsiflexion
* Plantar flexion
* Inversion
* Eversion
* Protraction
* Retraction
* Elevation
* Depression
* Opposition
🧠 Question 2: Can you provide examples of gliding movements?
✅ Answer:
Examples include:
Intercarpal joints (between the wrist bones)
Intertarsal joints (between the ankle bones)
Joints between the articular processes of vertebrae
🧠 Question 1: What are angular movements in joints?
✅ Answer:
Angular movements change the angle between two bones and occur along the sagittal plane.
🧠 Question 2: What is flexion in joint movements?
✅ Answer:
Flexion decreases the angle of the joint.
🧠 Question 3: What is extension in joint movements?
✅ Answer:
Extension increases the angle of the joint.
🧠 Question 4: What is hyperextension in joint movements?
✅ Answer:
Hyperextension is excessive extension beyond the normal range of motion.
🧠 Question 1: What are angular movements in the frontal plane?
✅ Answer:
Angular movements in the frontal plane include abduction, adduction, and circumduction.
🧠 Question 2: What is abduction in joint movements?
✅ Answer:
Abduction is the movement of a limb away from the midline of the body.
🧠 Question 3: What is adduction in joint movements?
✅ Answer:
Adduction is the movement of a limb toward the midline of the body.
🧠 Question 4: What is circumduction in joint movements?
✅ Answer:
Circumduction involves flexion, abduction, extension, and adduction of a limb to describe a cone in space.
🧠 Question 1: What is rotation in joint movements?
✅ Answer:
Rotation is the turning of a bone around its own longitudinal axis.
🧠 Question 2: Which joints allow rotation movements?
✅ Answer:
Examples include the joint between the C1 and C2 vertebrae, and the rotation of the humerus and femur.
🧠 Question 1: What is supination in terms of hand movement?
✅ Answer:
Supination is the turning of the hand backward (palm facing upward).
🧠 Question 2: What is pronation in terms of hand movement?
✅ Answer:
Pronation is the turning of the hand forward (palm facing downward).
🧠 Question 1: What is inversion in terms of foot movement?
✅ Answer:
Inversion is the movement where the sole of the foot turns medially (inward).
🧠 Question 2: What is eversion in terms of foot movement?
✅ Answer:
Eversion is the movement where the sole of the foot turns laterally (outward).
🧠 Question 3: What is dorsiflexion in terms of foot movement?
✅ Answer:
Dorsiflexion is the upward movement of the foot.
🧠 Question 4: What is plantar flexion in terms of foot movement?
✅ Answer:
Plantar flexion is the downward movement of the foot.
🧠 Question 4: What is retraction in terms of movement in the transverse plane?
✅ Answer:
Retraction is the posterior (backward) movement of a body part.
🧠 Question 3: What is protraction in terms of movement in the transverse plane?
✅ Answer:
Protraction is the anterior (forward) movement of a body part.
🧠 Question 1: What is elevation in terms of special movements?
✅ Answer:
Elevation is the movement of lifting a body part superiorly (upward).
🧠 Question 2: What is depression in terms of special movements?
✅ Answer:
Depression is the movement of moving a body part inferiorly (downward).
🧠 Question 3: What is opposition of the thumb?
✅ Answer:
Opposition is a movement in the saddle joint where the thumb touches the tips of the other fingers.
🧠 Question: What is a hinge joint, how does it function, and what are some examples?
✅ Answer:
A hinge joint is where a cylindrical-shaped projection of one bone fits into a trough-shaped surface of another bone.
Motion occurs within a single plane, resembling the action of a mechanical hinge.
It allows for flexion and extension in only one plane.
Examples:
Elbow joint
Knee joint
🧠 Question: What is a plane joint and what are some examples?
✅ Answer:
A plane joint has articular surfaces that are essentially flat. It allows only short slipping or gliding movements and no rotation around an axis.
Examples:
Intercarpal joints
Intertarsal joints
Joints between vertebrae
🧠 Question: What is a pivot joint, how does it function, and what movement does it allow?
✅ Answer:
A pivot joint involves the rounded end of a bone protruding into a ring of bone and ligaments on another bone.
The only movement allowed is rotation of the bone around its long axis.
Example:
The joint between the atlas (C1) and axis (C2) vertebrae in the neck.
🧠 Question: What is a condyloid joint, how does it function, and what is an example?
✅ Answer:
In condyloid joints, the oval articular surface of one bone fits into a complementary concavity in another.
Both articulating surfaces are oval shaped.
Example:
Metacarpophalangeal (MCP) joints in the fingers. These joints allow movement in two planes (flexion/extension and abduction/adduction).
🧠 Question: What is a saddle joint, how does it function, and what is an example?
✅ Answer:
Saddle joints resemble condyloid joints but allow greater freedom of movement.
Each surface has both a concave and a convex surface that fit together, resembling a saddle.
Example:
Carpometacarpal joints of the thumb. These joints allow a wide range of movement, including opposition, which is crucial for gripping.
🧠 Question: What are ball and socket joints, their features, and examples?
✅ Answer:
Ball and socket joints have a spherical head of one bone that fits into a cuplike socket of another.
They are multiaxial, allowing movement in all planes and around all axes, making them the most freely moving synovial joints.
Examples:
Shoulder joint
Hip joint
These joints allow for wide-ranging movements like rotation, flexion, extension, abduction, and adduction.
