HUBS191-Musculoskeletal system

The four basic types of tissue are...? (check all that apply)

The cells of [blank_start]connective[blank_end] tissue tend to be widely separated from each other. The large amounts of [blank_start]extra cellular matrix[blank_end] are found in these [blank_start]spaces[blank_end]. Loose connective tissue keeps [blank_start]organs[blank_end] and epithelial in place while [blank_start]dense[blank_end] connective tissue forms both [blank_start]ligaments[blank_end] and tendons. [blank_start]Adipose[blank_end] tissue (fat) is also connective tissue. [blank_start]Blood[blank_end], bone and [blank_start]cartilage[blank_end] are also kinds of connective tissue.

The main role of connective tissue in the body is to transport substances, and provide structure and support.

[blank_start]Epithelial[blank_end] tissue is arranged next to one another and there is little [blank_start]extracellular matrix[blank_end]. The tissue protects outer surfaces (our skin) and is lines [blank_start]internal cavities[blank_end].

What are the two types of bone tissue?

Long bones are wider than they are long

Carpal bones are what type of bone?

Metacarpals are in which type of bone class?

The scapula bone is a __________.

What type of bone is in this picture?

What are the two divisions of the skeleton?

How many bones are there for the cervical division in the vertebrae?

How many bones are there for the Thoracic division in the vertebrae?

How many bones are there for the lumbar division in the vertebrae?

Flexion is in the ___________ plane.

Extension is in the ________ plane.

How many ribs make up the ribcage?

Which bone does the clavicle articulate with?

It is possible to palpate the whole length of the clavicle because it is more [blank_start]superficial[blank_end] and no [blank_start]muscle[blank_end] is covering it.

Why bone does the scapula articulate with?

What bone is this?

what bone is pictured at the top?

What bone is this?

How many carpal bones are on the hand?

How many metacarpals are in the hand?

How many phalanges are in the hand?

How many tarsals are in a foot?

How many metatarsals are in the foot?

How many phalanges are in a toe of a foot (other than the big toe)?

An epicondyle is a [blank_start]prominence[blank_end] on the [blank_start]distal[blank_end] part of a [blank_start]long[blank_end] bone serving for the attachment of muscles and [blank_start]ligaments[blank_end].

The forearm is defined as the region from [blank_start]elbow[blank_end] to [blank_start]wrist[blank_end]. The forearm has two [blank_start]long[blank_end] bones, the [blank_start]radius[blank_end] and [blank_start]ulna[blank_end].

Bones are made of [blank_start]connective[blank_end] tissue; they consist of cells embedded in an [blank_start]extracellular matrix[blank_end]. Bones begin as [blank_start]cartilaginous[blank_end] preforms in infancy and [blank_start]ossify[blank_end] as we age. Because bones are [blank_start]alive[blank_end] and contain cells, they have the ability to adapt and [blank_start]repair[blank_end].

The [blank_start]ECM[blank_end] of a bone is different from other types of [blank_start]connective[blank_end] tissue as it only consists of [blank_start]1/3[blank_end] of organic material and [blank_start]2/3[blank_end] of [blank_start]inorganic[blank_end] material

What type of cell in the cellular component of the bone build the extracellular matrix?

What type of cell in the cellular component of the bone break down the extracellular matrix?

The outer surface of bone is covered and protected by the [blank_start]periosteum[blank_end], a fine sheet of [blank_start]connective[blank_end] tissue. There are small holes in the periosteum called [blank_start]foraminae[blank_end]. The foraminae allow blood vessels and [blank_start]nerves[blank_end] to pass into the bone and [blank_start]supply[blank_end] the cells. Osteocytes are found in living spaces called [blank_start]lacunae[blank_end], trapped in sheets of [blank_start]bone[blank_end] known as [blank_start]lamellae[blank_end]. Each lamellae is made up of [blank_start]collagen[blank_end] fibres that are [blank_start]arranged[blank_end] in a specific direction. Bone has many [blank_start]layers[blank_end] of lamellae and their [blank_start]collagen[blank_end] fibres run in many different directions, so bone is resistant to [blank_start]tension[blank_end] in many directions. Lamellae arrange themselves into [blank_start]cylinder[blank_end]-shaped structures known as [blank_start]osteons[blank_end].

A [blank_start]central canal[blank_end], through which blood vessels and [blank_start]nerves[blank_end] pass, runs down the middle of an [blank_start]osteon[blank_end]. Blood and nerves penetrate into the [blank_start]lacunae[blank_end] to supply the [blank_start]osteocytes[blank_end] through channels called [blank_start]canaliculi[blank_end] that connects to the lacunae to the central canal and to each other. These allow delivery of nutrients and [blank_start]removal[blank_end] of wastes.

In the middle of shafts of long bones is a cavity in which the bone marrow is found: the [blank_start]medullary cavity[blank_end]. Lining this is a fine sheet of connective tissue called [blank_start]endosteum[blank_end].

Cancellous bone is comprised of the same tissue as compact bone but it is arranged quit differently. [blank_start]Lamaellae[blank_end] form struts of bone known as [blank_start]trabeculae[blank_end], which interconnect to form a [blank_start]honeycomb[blank_end] or sponge-like structure. [blank_start]Bone marrow[blank_end] is found between the trabeculae. Trabeculae are thinner than [blank_start]osteons[blank_end], so osteocytes can communicate with each other and with nerves and blood vessels directly.

Bone growth first occurs in the [blank_start]diaphysis[blank_end]; as the bone develops, more [blank_start]bone[blank_end] is formed from the center [blank_start]outwards[blank_end] towards the [blank_start]end[blank_end] of bones. Then, blood vessels grow into the bone and are reshaped by [blank_start]osteoclast[blank_end]s so that the central cavity contains bone marrow.

Osteocytes reside in [blank_start]lacunae[blank_end].

Which fracture occurs when the bone breaks completely into two but there is no penetration of the skin, and very little damage to the surrounding soft tissue?

What type of fracture occurs when the bone breaks and pierces the skin, and results in serious soft tissue damage (the bone rips through muscles)? *greatly increases the possibility of infection as the bone is exposed.

Thickening, or addition of the bone, occurs at the [blank_start]subperiosteal[blank_end] surface, and bone is removed or resorbed (by [blank_start]osteoclasts[blank_end]) at the [blank_start]endosteal[blank_end] surface.

Osteoclasts remove bone by releasing [blank_start]lysosomes[blank_end] and [blank_start]acid[blank_end]. Enzymes break down the [blank_start]organic part[blank_end] of the bone tissue, and acid breaks down the [blank_start]inorganic part[blank_end].

In the first stage of fracture repair, broken blood vessels lead to a formation of a [blank_start]haematoma[blank_end] (a soft [blank_start]clot[blank_end]), which takes 0 to [blank_start]3[blank_end] days to form. [blank_start]Capillaries[blank_end] grow into the haematoma. [blank_start]Phagocytes[blank_end] (white blood cells) engulf the [blank_start]dead[blank_end] [blank_start]tissues[blank_end].

In stage 2 of a fracture repair, the next [blank_start]3[blank_end] days to [blank_start]2[blank_end] weeks, [blank_start]fibroblasts[blank_end] arrive through the [blank_start]capillaries[blank_end] and begin producing [blank_start]collagen[blank_end] fibres to form a matrix of collagen. Some of these fibroblasts differentiate into [blank_start]chondroblasts[blank_end]. They then form a [blank_start]soft[blank_end] [blank_start]cartilaginous[blank_end] [blank_start]callus[blank_end] that splints the bone ends together and [blank_start]reduces[blank_end] movement.

In stage 3 of bone fracture repair, which is during the next [blank_start]3[blank_end] to [blank_start]4[blank_end] weeks, [blank_start]osteoblasts[blank_end] transform the fibrocartilage callus ([blank_start]soft callus[blank_end]) into a [blank_start]bony callus[blank_end].

In stage 4 of fracture repair, the bone is completely [blank_start]united[blank_end] and converts [blank_start]bony[blank_end] callus into more organized [blank_start]osteon[blank_end] structure of bone tissue, and refashioning the bone into its original shape. This starts to happen [blank_start]2[blank_end] to [blank_start]3[blank_end] months after initial fracture has occurred, but it may take [blank_start]2[blank_end] years to completely [blank_start]remodel[blank_end].

The lower the [blank_start]bony[blank_end] congruence, the more [blank_start]soft[blank_end] [blank_start]tissue[blank_end] [blank_start]support[blank_end].

The overall function of a tendon is to restrict movement. and keep structures stable.

Chondrocytes are a [blank_start]cartilage[blank_end] cell; a former [blank_start]chondroblast[blank_end] that has become enclosed in a [blank_start]lacuna[blank_end] in the cartilage matrix.

Cartilage is [blank_start]avascular[blank_end] (contains no blood vessels), so [blank_start]nutrients[blank_end] and oxygen must diffuse through the [blank_start]ECM[blank_end] to nourish the [blank_start]chondrocytes[blank_end], so it takes a long time for cartilage to heal after an [blank_start]injury[blank_end] and it can never grow very thick.

Hyaline cartilage is [blank_start]thin[blank_end] and contains [blank_start]collagen[blank_end] fibres arranged randomly throughout the [blank_start]matrix[blank_end]. This arrangement traps [blank_start]water[blank_end] and makes hyaline cartilage appear smooth. It has less [blank_start]collagen[blank_end] and more [blank_start]water[blank_end] than fibrocartilage. It covers the [blank_start]articular[blank_end] surfaces of bones, and also allows bone surfaces involved with a joint to move against one another [blank_start]fluidly[blank_end] and with little friction.

The extracellular matrix of [blank_start]dense[blank_end] [blank_start]fibrous[blank_end] connective tissue consists of [blank_start]collagen[blank_end] fibres embedded in ground substances. [blank_start]Fibroblasts[blank_end] are spread throughout the [blank_start]ECM[blank_end]. The collagen is densely packed in [blank_start]one[blank_end] [blank_start]direction[blank_end], which makes the DFCT extremely good at resisting [blank_start]tension[blank_end]. DFCT is partially [blank_start]avascular[blank_end], it takes a long time for it to repair, but not as long as cartilage.

The shape of ends of [blank_start]bones[blank_end] involved in the [blank_start]joint[blank_end] determines the amount and type of [blank_start]movement[blank_end] possible at the joint. For example, the [blank_start]round[blank_end] head of the [blank_start]femur[blank_end] allows a wide range of [blank_start]movement[blank_end] at the [blank_start]hip[blank_end], and its deep [blank_start]articulation[blank_end] with the hip gives the joint stability.

Articular cartilage covers the bones where they [blank_start]meet[blank_end] and promotes a [blank_start]frictionless[blank_end] surface.

In a synovial joint, the thickenings of capsule form the [blank_start]capsular[blank_end] ligaments. These reinforce joints and [blank_start]restrict[blank_end] movement where it is not [blank_start]required[blank_end]. For example, the capsular ligaments at the knee joint are called [blank_start]collateral[blank_end] ligaments and prevent [blank_start]adduction[blank_end] and abduction.

The ligaments of a synovial joint may be divided into [blank_start]extra-[blank_end]capsular ligaments (those that lie outside the capsule), [blank_start]capsular[blank_end] ligaments (those that are thickened and parts of the capsule) and [blank_start]intra[blank_end]-capsular ligaments (those that lie within the capsule).

The hinge joint is a bone joint in which the [blank_start]articular[blank_end] surfaces are [blank_start]molded[blank_end] to each other in such a manner as to permit motion only in [blank_start]one[blank_end] plane. It permits motion back and forth like a [blank_start]door[blank_end]. This joint creates movement of [blank_start]flexion[blank_end] and extension. An example of a hinge joint are the [blank_start]interphalangeal[blank_end] joints in the [blank_start]finger[blank_end].

One type of a synovial joint, is a [blank_start]pivot[blank_end] joint, which is [blank_start]uniaxial[blank_end]. This joint allows for [blank_start]supination[blank_end] and pronation. An example includes the [blank_start]radioulnar[blank_end] joints (both proximal and [blank_start]distal[blank_end]).

The saddle joint is [blank_start]biaxial[blank_end] and creates movements such as flexion & [blank_start]extension[blank_end] and also abduction & [blank_start]adduction[blank_end], which ultimately causes [blank_start]circumduction[blank_end]. An example of this joint is [blank_start]carpometacarpal[blank_end] joint at the base of the [blank_start]thumb[blank_end].

The ellipsoid joint is [blank_start]biaxial[blank_end] and causes flexion, [blank_start]extension[blank_end], adduction, [blank_start]abduction[blank_end] and [blank_start]circumduction[blank_end]. An example is the [blank_start]radiocarpal[blank_end] joint which is located in the [blank_start]wrist[blank_end].

The plane joint is [blank_start]multi-axial[blank_end] and causes sliding/[blank_start]gliding[blank_end]. The [blank_start]intercarpal[blank_end] and intertarsal joints, which are between carpal and [blank_start]tarsal[blank_end] bones, are an example.

Ball and socket joints are [blank_start]multiaxial[blank_end], and therefore can cause [blank_start]adduction[blank_end], abduction, [blank_start]flexion[blank_end], extension, circumduction and [blank_start]rotation[blank_end]. An examples include the [blank_start]hip[blank_end] joint and the shoulder joint.

The three types of tissue involved in the structure of a muscle are the [blank_start]epimysium[blank_end], perimysium and endomysium. The epimysium is a layer of connective tissue that wraps around the whole muscle. The [blank_start]perimysium[blank_end] wraps around the fascicles inside the muscle. The [blank_start]endomysium[blank_end] wraps around each [blank_start]myocyte[blank_end]. All of these tissues will eventually connect to one another and form a [blank_start]tendon[blank_end] that connects the skeletal muscle to the [blank_start]skeleton[blank_end]. Therefore, the layers of connective tissue support the muscle and transmit the [blank_start]force[blank_end] of contraction to the bones.

Each skeletal muscle is comprised of [blank_start]fascicles[blank_end] and each fascicle is made up of muscle cells called [blank_start]myocytes[blank_end]. Myocytes are long , skinny and [blank_start]cylindrical[blank_end] cells and are multi-[blank_start]nucleated[blank_end]. They are made of [blank_start]myofibrils[blank_end], which are made up of [blank_start]myofilaments[blank_end]. Myofilaments come in two different varieties: [blank_start]thick[blank_end] filament of myosin and [blank_start]thin[blank_end] filament of [blank_start]actin[blank_end]. The myosin and actin proteins are arranged in a contractile units called [blank_start]sarcomeres[blank_end] and work together to produce muscle [blank_start]contraction[blank_end].

Muscle is striated because....

The boundaries of sarcomeres are marked by [blank_start]Z[blank_end]-lines. These are placed at [blank_start]regular[blank_end] intervals along the [blank_start]myofibril[blank_end], and anchor the thin [blank_start]actin[blank_end] filaments together. The [blank_start]thick[blank_end] myosin filament lies in the [blank_start]middle[blank_end] of the sarcomere. During muscle contraction, the thick myosin filaments [blank_start]pull[blank_end] on the thin actin filaments, causing the [blank_start]actin[blank_end] to slide over the [blank_start]myosin[blank_end]. This draws Z lines together and shortens the [blank_start]sarcomeres[blank_end].

The size of a motor unit can vary. A small motor unit enables [blank_start]fine[blank_end] control as each [blank_start]action[blank_end] [blank_start]potential[blank_end] only causes the contraction of a small number of [blank_start]myocytes[blank_end]. Small motor units are therefore found in muscles that move eyes and fingers. Large motor units are found in areas where fine control is not found, such as the [blank_start]gluteus[blank_end] maximus.

Activation of motor units is an 'all' or 'nothing' response: either all the [blank_start]myocytes[blank_end] innervated will contract, or none of them will. However, whole muscles can contract with different amounts of [blank_start]force[blank_end]. The force of contraction depends on the number of [blank_start]active[blank_end] motor units, the [blank_start]frequency[blank_end] of [blank_start]action[blank_end] potentials arriving at the motor unit and the [blank_start]size[blank_end] of the motor unit.

The muscle is active and develops tension, and shortening of sarcomeres follows. This leads to the whole muscle shortening and therefore a change in joint position. What type of muscle action is this?

The muscle is active and develops tension, but there is no change in sarcomere length. The muscle itself does not change in length, and there is no change in joint positions. What muscle action is this?

The muscle is active and develops tension, and the lengthening of the sarcomeres follows. This leads to the whole muscle lengthening, and therefore a change in joint position. Which type of muscle action is this?

A muscle that is creating a movement by contracting concentrically. Which muscle role is this?

A muscle that is opposing a movement by contracting eccentrically. Which muscle role is this?

A muscle that is holding a joint still by contracting isometrically. What type of muscle role is this?

A muscle that eliminates the unwanted movement, so that another movement may occur. What type of muscle role is this?

If the muscle is [blank_start]anterior[blank_end] to the joint, concentric action will produce flexion.

If a muscle is [blank_start]posterior[blank_end] to the joint, concentric action will cause extension.

If a muscle is lateral to the joint, concentric action will produce [blank_start]adduction[blank_end].

If the muscle is [blank_start]medial[blank_end] to the joint, concentric action will produce adduction.

The [blank_start]controlled variable[blank_end] is the variable that the system is trying to keep the same. The [blank_start]set point[blank_end] is the optimal target for the variable to be at. The [blank_start]reference range[blank_end] is the range of acceptable limits of that variable.

[blank_start]Feedback loops[blank_end] can either be positive or negative. A [blank_start]positive[blank_end] loop causes an increase in response (stretch in giving birth), where as a negative loop causes a decrease in response (change in temperature).

What is the receptor that detects a change in a controlled variable?

The [blank_start]control center[blank_end] compares the change in the [blank_start]controlled variable[blank_end] to the set point and elicits an appropriate response.

The [blank_start]effector[blank_end] uses mechanisms to bring about change in the controlled variable, according to information received from the [blank_start]control center[blank_end].

[blank_start]Feedforward[blank_end] is when a sensor senses a [blank_start]change[blank_end] in the controlled variable and immediately effects a change to resist it, bypassing the integration center (anticipation). Usually is complimentary to [blank_start]negative[blank_end] [blank_start]feedback[blank_end], so any mistakes can be fixed, or response can be exaggerated. An example of this is gag reflex.

Flexion and extension occur on the [blank_start]sagittal[blank_end] [blank_start]plane[blank_end]. Abduction and adduction occur on the [blank_start]coronal[blank_end] [blank_start]plane[blank_end].

[blank_start]Cancellous[blank_end] bone has a high surface area to mass ratio, as it is less [blank_start]dense[blank_end] than compact bone. The main functional unit is the [blank_start]trabeculae[blank_end], which are aligned towards the distribution of mechanical force on the bone, helping to absorb the [blank_start]impact[blank_end]. Often found in the [blank_start]ends[blank_end] of the bone.

[blank_start]Osteocytes[blank_end] originate from osteoblasts once they become trapped in the [blank_start]ECM[blank_end]. Their function is to maintain [blank_start]bone[blank_end] tissue. Osteoblasts originate from [blank_start]osteoprogenitor[blank_end] cells and are found in areas of growth. Their function is to secrete bone [blank_start]matrix[blank_end]. Osteoclasts originate from [blank_start]macrophages[blank_end] and their function is to [blank_start]break[blank_end] [blank_start]down[blank_end] bone tissue during the remodeling and healing of bone.

Each lacunae is connected to one another via [blank_start]canaliculi[blank_end].

A fracture occurs when bone tissue is broken as a result of external force. Bone tissue is highly vascularized and so there is often a lot of [blank_start]bleeding[blank_end] associated with the injury. Bone tissue also has an extensive [blank_start]nerve[blank_end] supply which is why there is a lot of pain involved with a fracture. The first stage is [blank_start]haematoma[blank_end] [blank_start]formation[blank_end], which is when a blood clot forms around the site of injury to stop excessive bleeding. This is important because excessive blood [blank_start]loss[blank_end] leads to death and reparative cells arrive to the site of injury through [blank_start]blood[blank_end] [blank_start]supply[blank_end]. A process known as [blank_start]angiogenesis[blank_end] then occurs to increase [blank_start]vascular[blank_end] supply to the fracture. [blank_start]Phagocytes[blank_end] arrive from the blood capillaries and clean up the dead tissue and debris. After that, stage 2 occurs when the [blank_start]soft[blank_end] callus forms. [blank_start]Fibroblasts[blank_end] arrive at the site of injury where they differentiate into [blank_start]chondroblasts[blank_end]. The chondrocytes secrete a [blank_start]cartilaginous[blank_end] matrix forming a fibrocartilaginous callus (this callus is soft because it is made up of cartilage, not bone). Stage three is when the [blank_start]hard[blank_end] callus forms; the [blank_start]osteoblasts[blank_end] turn fibrocartilaginous callus into a hard boney callus is a process known as ossification. The last stage is when [blank_start]osteoclasts[blank_end] and osteoblasts work together to remodel the bone into its normal [blank_start]arrangement[blank_end].

Fibrocartilage are high quantities of [blank_start]collagen[blank_end] bundles aligned towards the [blank_start]direction[blank_end] or pressure. Main function is to resist [blank_start]tension[blank_end]. Found where some movement is required but [blank_start]stability[blank_end] is also needed, for example the [blank_start]menisci[blank_end] of the knee joint.

This structure in a synovial joint is found at points of articulation within the joint. This acts to facilitate frictionless movement between the two bones.

A ___________ surrounds the joint, which is thicker where support is required and thinner where movement is required.

What provides the articular cartilage with nutrients and lubricates the synovial joint?

what does the synovial membrane do?

Which of the following is the correct order?

Muscle form depends on three factors: 1) Length of muscle fibres: [blank_start]Long[blank_end] muscle fibres = larger [blank_start]ROM[blank_end]. 2) Number of muscle fibres: higher number of fibres means more [blank_start]tension[blank_end] can be generated, thus more strength 3) Arrangement of muscle fibres: Fibres can be parallel or [blank_start]pennate[blank_end].