Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Anatomy > Chapters 6-11 > Flashcards

Chapters 6-11 Flashcards

1
Q

What does the Latin prefix “peri-“ mean?

A

around

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does the Latin root “chondr-“ mean?

A

cartilage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a perichondrium?

A

Membrane of fibrous connective tissue that covers the external surface of cartilages.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What type of tissue is perichondrium generally made of? What type of cells would you find in it?

A

Tissue: dense irregular connective tissue
Cells: fibroblasts and chondroblasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

what is the dominant cell type in cartilage? What are the spaces in the matrix that house these cells?

A

chondrocyte housed in the lacuna

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe the structure of hyaline cartilage.

A

chondrocytes in the lacuna; extracellular matrix fiber is collagen unit fibril that is too thin to be seen with a light microscope.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Where in the adult body is hyaline cartilage located? Where in an embryo?

A

It is the most common type of cartilage located at the sternal end of the costa, in respiratory structures such as the trachea, larynx, nasal and bronchi, and at the end of long bones. In the embryo hyaline cartilage forms the embryonic skeleton - before week 8 the skeleton of the human embryo consists only of hyaline cartilage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe the functional properties of hyaline cartilage. Illustrate these properties by describing a specific situation where they are important.

A

provides support through flexibility and resilience; firmness and flexibility; It is present at the end of long bones such as at the end of the humerus and at the ends of the radius and ulna so that when we bend our arm, the ends of the bones don’t scrape together, rather they glide smoothly.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the structure of elastic cartilage.

A

chondrocytes in the lacuna; extracellular matrix similar to hyaline but contains many elastic fibers along with the collagen fibrils.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe the functional properties of elastic cartilage. Illustrate these properties by describing a specific situation where they are important.

A

more elastic than hyaline cartilage and better able to tolerate repeated bending; elastic fibers make it elastic. The outer ear (auricles) are elastic cartilage so that they are able to bend significantly and return to normal shape.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Where in the adult body is elastic cartilage located?

A

in the epiglottis at the larynx and in the outer ear (auricles)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe the structure of fibrocartilage.

A

chondrocyte in the lacuna; extracellular matrix made up of thick collagen fibers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Describe the functional properties of fibrocartilage. Illustrate these properties by describing a specific situation where they are important.

A

provides firmness and resists compression like hyaline cartilage with high tensile strength to resist strong tension (pulling) forces. It is in the intervertebral discs of our spine so that when we move the disc can compress on one side while stretching on the other allowing us to bend and then return to normal resting place maintaining it’s regular shape.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Where in the adult body is fibrocartilage located?

A

It is located in the intervertebral discs and in the articular discs of some joints such as in the menisci of the knee.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Explain why each individual bone of the body is considered an organ.

A

An organ is defined as a part of the body formed of two or more tissues and adapted to carry out a specific function. The bones of the skeleton are organs because they contain several different tissues. (bone tissue, nervous tissue, blood tissue, cartilage, and epithelial tissue)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

List the 5 functions of bones.

A
  1. Support
  2. Movement
  3. Protection
  4. Mineral storage
  5. Blood cell formation and energy storage
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Explain how bone provides support. Illustrate your explanation with an example. Explain what it is about bone tissue that allows for this function.

A

Its hard, rigid framework supports the weight of the body.
Example: the bones of the legs are pillars that support the trunk of the body in the standing person. The bone is hard and rigid and does not bend.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Explain how bone permit movement. Illustrate your explanation with an example. Explain what it is about bone tissue that allows for this function.

A

Skeletal muscles attach to the bones by tendons and use the bones as levers to move the body and its part. Because the bone is rigid and does not bend the whole structure moves.
Example: when the muscles in our biceps contract it pulls our entire forearm up allowing us to bend our arm.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Explain how bone provides protection. Illustrate your explanation with an example. Explain what it is about bone tissue that allows for this function.

A

The hard rigid structure of the bone provides protection when they wrap around other more vulnerable parts of the body.
Example: the bones of the skull form a protective case for the brain.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Explain how bone provides for mineral storage. Illustrate your explanation with an example. Explain what it is about bone tissue that allows for this function.

A

Bones serve as a reservoir for minerals, the most important of which are calcium and phosphate. They are released into the bloodstream as ions for distribution to all parts of the body as needed.
Example: the bones stores calcium and releases it during resorption.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Explain how bones provide for cell formation and energy storage. Illustrate your explanation with an example. Explain what types of tissues are in bones that allow for these functions.

A

Bones contain red and yellow bone marrow. Red bone marrow (hematopoietic tissue) makes the blood cells and yellow marrow (adipose tissue) is a site of fat storage.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Describe the composition of the extracellular matrix of bone tissue.

A

1/3 organic components - collagen

2/3 inorganic components - hydroxyapatites (minerals) primarly calcium phosphate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Explain the different physical properties of each of the components of the matrix of bone tissue. Illustrate each by describing a specific example and explain why it is important

A

1/3 organic - High tensile strength, easy to bend; soft
-Allows bone to resist stretching and twisting.
2/3 inorganic - hard; rigid, incompressible, brittle
-Enables it to resist compression.
**Together (the right combination) allows bone to be exceedingly durable, strong and resilient without being brittle.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are the three types of cells found in bone tissue? Explain what each cell type does. Illustrate the function of each cell by describing the specific activities of the cell that allow it to accomplish its specific function.

A
  1. Osteoblasts - (osteo = bone, blast = bud, sprout) “bone builder” - Cells that actively produce and secret the organic components of the bone matrix (osteoid): the ground substance and the collagen fibers.
  2. Osteocytes - (osteo = bone, cyte = cell) - Osteoblasts that no longer produce new osteoid and function to keep the bone matrix healthy; responds to stresses
  3. Osteoclasts - (osteo = bone, clast = break) - Bone destroying cell; responsible for resorption of bone. Produced from red bone marrow and secrete hydrochloric acid which dissolves the mineral component of the matrix and lysosomal enzymes which digest the organic components. (example: if not getting enough calcium, the osteoclasts will eat away at bones in order to release the reserved calcium and provide it to the body.)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What does the Latin root “osteo-“ mean?

A

bone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What does the Latin root “blast-“ mean? How is it used in histology?

A

bud, sprout - used to represent “builder”

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Define the term “long bone.” Give three examples of long bones. (Be able to pick the long bones out of a list.)

A

Bones that are considerably longer than they are wide. They have a shaft plus two distinct ends.

  1. phalanges
  2. femur
  3. humerus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Define the term “short bone.” Give three examples of short bones. (Be able to pick them short bones out of a list.)

A

Bones that are roughly cube-shaped; occur in the wrist and ankle.

  1. talus
  2. patella
  3. scaphoid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Define the term “flat bone.” Give three examples of flat bones. (Be able to pick the flat bones out of a list.)

A

Bones that are thin, flattened, and usually somewhat curved.

  1. sternum
  2. scapula
  3. cranial bones (parietal, frontal, temporal, occipital)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Define the term “irregular bone.” Give three examples of irregular bones. (Be able to pick the irregular bones out of a list.)

A

Bones that have various shapes that do not fit into the previous categories.

  1. vertebrae
  2. hip bones
  3. hyoid
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Explain where compact and spongy bone is found in a long bone, a flat bone, and a short bone.

A
  1. long bone - spongy bone is found at the ends of long bones (epiphysis) and the compact bone makes up the shaft (diaphysis) and outside layer of the epiphysis.
  2. flat bone - spongy bone sandwiched between two thin layers of compact bone.
  3. short bone - spongy bone surrounded by a thing layer of compact bone.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What structures would be found in a simple diagram of a typical long bone?

A

Shaft, proximal and distal epiphysis, epiphyseal lines, articular cartilage, medullary cavity, periosteum, endosteum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

What type of tissue is found in the medullary cavity of long bones?

A

yellow bone marrow (adipose tissue)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What are the names of the membranes that line the outer and internal surfaces of a bone? What type of tissue are they made of? What are the functions of the membranes?

A

Outer surface - periosteum (“around the bone”): a connective tissue membrane that has two sublayers.
1. superficial layer of dense irregular connective tissue which resists tension plea on a bone during bending.
2. deep osteogenic layer containing bone-depositing cells (osteoblasts) and bone-destroying cells (osteoclasts) which remodel bone surfaces throughout our lives.
Internal surface - endosteum (“within the bone”): thin connective tissue membrane that covers the trabecular of spongy bone and lines the central canals of osteons. It is also osteogenic, containing both osteoblasts and osteoclasts.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

What types of stresses do the two sides of a bone typically receive? Explain what it is about bone tissue that allows the bone to withstand these forces.

A

compression on one side and tension (stretching) on the other. To resist, the strong, compact bone tissue occurs in the external portion of the bone where stress is the greatest.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What structures would be found in a simple diagram of the microscopic anatomy of compact bone?

A

osteon and it’s parts: central canal, osteocytes, canaliculi, lacunae, lamellae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

Explain the function of canaliculi. Explain why these structures are important.

A

“little canals” that run through the matrix connecting neighboring lacunae to one another and to the nearest capillaries, such as those in the central canals. Within the canaliculi the extensions of neighboring osteocytes touch each other and form gap junctions, from one osteocyte to the next. This direct transfer is the only way to supply the osteocytes with the nutrients they need because the intervening bone matrix is too solid and impermeable to act as a diffusion medium.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

Name the two processes that produce bones. Briefly describe each process. Which bones of the body are formed by each of these processes?

A

Intramembranous ossification - membranous bones form directly form mesenchyme without first being modeled in cartilage. All bones of the skull, except a few at the base are in this category along with the clavicles.:
1. Ossification centers appear in the fibrous connective tissue membrane. (During week 8 of embryonic development) 2. Bone matrix (osteoid) is secreted within the fibrous membrane and calcifies. 3. Woven bone and periosteum form. 4. Lamellar bone replaces woven bone, just deep to the periosteum and red marrow appears.

Endochondral ossification - bones that are first modeled by hyaline cartilage, which then is gradually replaced by bone tissue. All bones from the neck down except for the clavicles are endochondral bones.:
1. Bone collar forms around the diaphysis of the hyaline cartilage model. (late embryo - 8 weeks) 2. Cartilage in the center of the diaphysis calcifies and then develops cavities. 3. The periosteal bud invades the internal cavities, ad spongy bone begins to form. 4. The diaphysis elongates and a medullary cavity forms as ossification continues. Secondary ossification centers appear in the epiphyses. 5. The epiphyses ossify. When completed, hyaline cartilage remains only in the epiphyseal plates and articular cartilages.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What would be included in a diagram of a long bone at about week 9 of development?

A

Hyaline cartilage, bone collar, primary ossification center

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

What would be included in a diagram of a long bone near birth?

A

1st and 2nd ossification centers, hyaline cartilage, medullary cavity, epiphyseal blood vessel, spongy bone formation, blood vessel of periosteal bud.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

What would be included in a diagram of a long bone during childhood and adolescence?

A

Articular cartilage (hyaline), spongy bone, epiphyseal plates (hyaline cartilage), medullary cavity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

What would be included in a diagram of an epiphyseal plate as found in a long bone during childhood.

A

resting zone, proliferation zone, hypertrophic zone, Calcification zone, ossification zone, bone, osteoblasts & osteoclasts

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

What is occurring in each of the four zones of the epiphyseal plate?

A
  1. Proliferation plate - Cartilage cells undergo mitosis dividing quickly pushing the epiphysis away from the diaphysis causing the entire long bone to lengthen.
  2. Hypertrophic zone - Older cartilage cells enlarge signaling the surrounding matrix to calcify.
  3. Calcification zone - Matrix becomes calcified; cartilage cells die; matrix begins deteriorating.
  4. Ossification zone - new bone forms
    (5. resting zone - a relatively small and inactive zone of cartilage cells nearest the epiphysis.)
44
Q

Explain why and when people stop growing.

A

As adolescence draws to an end, the chondroblasts in the epiphyseal plates divide less often, and the plates become thinner. Eventually, they exhaust their supply of mitotically active cartilage cells, so the cartilage stops growing and is replaced by bone tissue. Long bones stop lengthening when the bone of the epiphyses and diaphysis fuses.

45
Q

Where and when does appositional bone growth occur? Does this only occur during childhood and adolescence? Explain.

A

Appositional growth - growth of a bone by the addition of bone tissue to its surfaces; the circumference of the long bone expands and the bone widens.
This happens as the bone lengthens and is regulated by the same hormones which stimulate the epiphyseal plates to grow and later close ending bone growth.

46
Q

Describe the 2 processes involved in bone remodeling. Be sure to include the cells involved in each process, and the activities of those cells that allow bones to be remodeled.

A
  1. bone resorption - osteoclasts crawl along bone surfaces breaking down the bone tissue. It forms a tight seal against the bone and secretes concentrated HCl which dissolves the mineral part of the matrix. Lysosomal enzymes are also released which digest the organic part of the matrix.
  2. bone deposition - osteoblasts lay down organic osteoid on bone surfaces, and calcium slats crystallize within this osteoid. osteoblasts transform into osteocytes when they are surrounded by bone matrix.
47
Q

Explain why bones are continually remodeled. (2 reasons) Illustrate each reason with an example. (be sure to include hormones if they are involved)

A
  1. Bone remodeling helps maintain constant concentrations of Calcium and phosphate ions in body fluids. example: when the concentration of calcium in the body fluids starts to fall, a hormone is real eased by the parathyroid glands of the neck which stimulates osteoclasts to resorb bone to release more into the blood.
  2. Bone is remodeled in response to the mechanical stress it experiences. Bone grows thicker in response to the forces experienced during exercise and gains in weight. In the absence of mechanical stress, bone tissue is lost. example: If a person gains a significant amount of weight it puts stress on the bones which in turn triggers them to grow thicker to support it.
48
Q

Describe the 4 phases of healing following a bone fracture.

A
  1. A hematoma forms
  2. fibrocartilaginous callus forms
  3. Bony callus forms
  4. Bone remodeling occurs
49
Q

Define “osteoporosis.” Which groups of people are more likely to develop it? What things must a person do when she/he is “young” to avoid it? What are the common types of fractures that occur with osteoporosis?

A
  • osteoporosis - low bone mass
  • Groups of people - aged white women who have gone through menopause
  • proper diet and exercise during the adolescent and early adulthood is crucial for developing and maintaining healthy bone in later life.
  • common types of fractures - comminuted (bone fragments into three or more pieces), compression (bone is crushed)
50
Q

What does the Greek root “arthro-“ mean? how is it used in anatomy?

A

“joints”

used to describe articulations of bones

51
Q

Name and describe the 3 functional classifications of joints? Give an example of each type.

A
  1. synarthrosios - immovable joints ( skull bones)
  2. amphiarthrosis - slightly moveable joints (intervertebral discs, pubic symphysis)
  3. diarthrosis - freely moveable joints (shoulder, knee, hip, wrist, ankle)
52
Q

What are the structural and functional characteristics of fibrous joints?

A

bones connected by fibrous tissue, namely dense regular CT, no joint cavity, immovable or only slightly moveable.

53
Q

What are the structural characteristics of sutures? Classify sutures based on the amount of movement that occurs between the bones. Where are sutures found in the body?

A

joint is held together by very short interconnecting collagenic fibers and bone edges interlock - immobile (synarthrosis) - found only in skull

54
Q

What are the structural characteristics of gomphoses? Classify based on the amount of movement that occurs between the bones. Where are they found in the body?

A

peg-in-socket fibrous joint connected by the periodontal ligament - immobile - articulation of a tooth with its socket.

55
Q

What are the structural characteristics of synchondrosis? Classify based on the amount of movement that occurs between the bones. Where are they found in the body? What about during childhood?

A

bones united by hyaline cartilage, immobile - joint between first rib and sternum - the epiphyseal plate during childhood

56
Q

What are the structural characteristics of symphysis? Classify based on the amount of movement that occurs between the bones. Where are they found in the body? Explain the function of a symphysis and how the types of tissues found there contribute to these functions.

A

bones united by fibrocartilage, slightly moveable - intervertebral discs and the pubic symphysis of the pelvis - function: fibrocartilage resists both tension and compression and can act as a resilient shock absorber, hyaline articular cartilage is also present on the obey surfaces to reduce friction between bones during movement. Together they provide strength with flexibility.

57
Q

What would be labeled in a simple diagram of the generalized structure of a synovial joint?

A

ligament, joint cavity containing synovial fluid, articular (hyaline) cartilage, articular layer containing the fibrous layer and synovial membrane, periosteum

58
Q

Explain the role of hyaline cartilage in a synovial joint. What is the hyaline cartilage called here?

A

called articular cartilage. covering the ends of the opposing bones; spongy cushions that absorb compressive forces placed on the joint and thereby keep the bone ends from being crushed.

59
Q

Describe the structure of the articular capsule of a synovial joint. include the types of tissue that contribute to the capsule.

A

a two layered joint capsule. outer fibrous layer of dense irregular connective tissue continuous with the periosteum layer of the joining bones. inner layer is a synovial membrane composed of loose connective tissue.

60
Q

Explain where synovial fluid comes from. Describe the functions of the synovial fluid. Illustrate these functions with examples and explain why these functions are important.

A

synovial fluid is primarily a filtrate of blood, arising from capillaries in the synovial membrane.
functions: 1. lubricant (allows adjoining bones to move across each other with a minimum of friction) 2. provides nutrients

61
Q

Some synovial joints possess an articular disc also called a what? What type of tissue is it made of? Name 2 joints that possess such a structure. Illustrate the function of the disc in one of these joints.

A

also called a meniscus.
made of fibrocartilage.
location: temporomandibular jlint, sternoclavicular joint, knee joint
An articular disc fills the gaps and improves the fit of some joints whose articulating bone ends have somewhat different shapes. Also allows two different movements at the same joint. example: jaw joint - allows two movements across each face of the disc.

62
Q

What are bursae and tendon sheaths? What is the function of these structures. Describe one place in the body they are found and explain their importance.

A

closed bags of lubricant that act like “ball bearings” to reduce friction between body elements that move over one another.
Bursae - “purse” - a flattened fibrous sac lined by a synovial membrane. Occur where ligaments, muscles, skin, tendons, or bones overlie each other and rub together. (found between head of humerus and and tendon)
Tendon sheath - an elongated bursa that wraps around a tendon like a bun around a hot dog. occur only on tendons that are subjected to friction, such as those that travel through joint cavities or are crowded together within narrow canals. carpal tunnel of the wrist contains a tendon sheath)

63
Q

What are the 4 general types of movements that can occur at synovial joints. Illustrate each type of movement by describing a specific example.

A

Gliding - Sliding the flat surfaces of two bones across each other (side to side of wrist)
Angular movements - Flexion, extension, abduction, adduction, circumduction (nodding of the head)
Rotation - Medial and lateral rotation; turning a bone around the longitudinal axis (turning the head from side to side)

64
Q

Define “flexion” as it is used to describe the movement at a joint.

A

decreasing the angle between two bones

65
Q

Define “extension” as it is used to describe the movement at a joint.

A

increasing the angle between two bones

66
Q

Define “abduction” as it is used to describe the movement at a joint.

A

moving a limb away from the body midline

67
Q

Define “adduction” as it is used to describe the movement at a joint.

A

moving a limb toward the body midline

68
Q

What types of movement are permitted at a plane joint. List the plane joints found in the body.

A

gliding movement (intercarpal joints, intertarsal joints, joints between vertebral articular surfaces)

69
Q

What types of movement are permitted at a hinge joint. list the hinge joints found in the body.

A

flexion and extension (elbow joints interphalangeal joints, knee)

70
Q

What types of movement are permitted at a pivot joint. list the hinge joints found in the body.

A

rotation (radius-ulna, atlas-axial joint)

71
Q

What types of movement are permitted at a condylar joint. list the hinge joints found in the body.

A

flexion and extension, adduction and abduction (knuckle joints, wrist joints)

72
Q

What types of movement are permitted at a ball-and-socket joint. list the hinge joints found in the body.

A

flexion and extension, adduction and abduction, rotation (shoulder joints, hip joints)

73
Q

Describe the role of muscle tone at joints, Illustrate this function with an example.

A

skeletal muscles contract and can stabilize joints.

example: femur & tibia

74
Q

Describe the anatomy of the shoulder joint. What hyaline cartilage structure helps create a deeper “socket”? Which large ligament greatly strengthens the capsule? the tendons from which 5 muscles surround the capsule and greatly stabilize it?

A

glenohumeral joint - glenoid cavity of the scapula articulates with the head of the humerus in a ball-and-socket joint deepened by the glenoid labrum.
Coracohumeral ligament greatly strengthens the capsule.
5 muscles: biceps brachii, subscapularis, supraspinatus, infraspinatus, teres minor

75
Q

Describe the anatomy of the knee joint. Name the large anterior bursar that can be damaged by continuous kneeling. Name the menisci. Name the 2 intracapsular ligaments and describe what the role of each is in the joint. Tendons from which two muscle groups help stabilize this joint?

A
  • largest and most complex modified hinge joint.
  • Subcutaneous prepatellar bursa is often injured.
  • Two fibrocartilage menisci occur within the joint cavity, between the femoral and tibial condyles - lateral and medial menisci
  • 2 intracapsular ligaments - anterior and posterior cruciate ligaments. They act as restraining straps to prevent undesirable movements at the knee joint. Anterior helps prevent anterior sliding of the tibia. posterior prevents forward sliding of the femur or backward displacement of the tibia. Together lock the knee when one stands.
  • Quadriceps muscle group and hamstring muscle group help stabilize
76
Q

Describe the 4 functional properties that distinguish muscle tissue from other tissues. Explain each.

A
  1. Contractility - able to shorten with force (pull itself shorter)
  2. Excitability - apply a stimulus and get a reaction (apply chemical such as neurotransmitter or hormone and will contract)
  3. Extensibility - you can make it longer (stretch it out) Can stretch skeletal muscle to 150% without damage
  4. elasticity - after you stretch it, it has the ability to return to its resting length
77
Q

What does the latin root “myo-“ or “mys-“ mean?

A

both mean muscle

78
Q

What does the latin root “sarco-“ mean?

A

flesh

79
Q

Describe each of the four functions that muscle tissue has in the body. Illustrate each function with a specific example.

A
  1. Produce movement - skeletal uncle attaches to the skeleton and moves the body by moving the bones.
  2. Open and close body passageways - (sphincter muscles) encircle many body openings and function as valves: relaxing to allow passage of a substance, contracting to close the passageway. Muscle tissue around the mouth and eyes opens and closes these body orifices.
  3. Maintain posture and stabilize joints - When we are awake, skeletal muscles contract continuously to maintain posture, enabling the body to remain in a standing or sitting position.
  4. Generate heat - muscle contraction produces heat which plays a vital role in maintaining normal body temperature. (when we exercise, excess heat generated during exercise stimulates sweating to cool us down.)
80
Q

What are the 3 types of muscle tissue? Describe each type in terms of how it is controlled, the shape of the cells, and presence/absence of striations, number of nuclei and where each type is found in the body (name specific organs).

A 
1. Skeletal muscle tissue - organs that attach to and move the skeleton
Control: voluntary; can be moved at will. 
Cell shape: elongated cylinders
Striations: yes
Number of nuclei: many
Location: skeletal muscles
2. Cardiac Muscle tissue 
Control: involuntary
Cell shape: branched
Striations: yes
Number of nuclei: one
Location: wall of the heart
3. Smooth Muscle Tissue
Control: involuntary
Cell shape: elongated fusiform with tapered ends
Striations: no
Number of Nuclei: one
Location: walls of hollow organs such as stomach, urinary bladder, blood vessels, and respiratory tubes.
81
Q

The outmost layer of CT of a skeletal muscle is called what? What type of tissue is it composed of?

A

Epimysium - an outer layer of dense irregular connective tissue that surrounds the whole skeletal muscle.

82
Q

What are tendons? What tissue type are tendons composed of? Explain how the properties of this tissue type allow tendons to function.

A

Tendon - tough band of fibrous connective tissue that joins skeletal muscles to bones. (dense regular CT)
Dense regular CT is extremely strong keeping the muscle attached to the bone while under force.

83
Q

Generally how many peripheral nerves innervate a particular skeletal muscle?

A

one

84
Q

Define terms “origin” and “insertion” as they are used with respect to skeletal muscles.

A

The attachment of the muscle on the less movable bone (larger bone, more massive body part) is called the origin of the muscle, whereas the attachment on the more movable bone (smaller bone) is called the muscle’s insertion. Thus when the muscle contracts, its insertion is pulled toward its origin.

85
Q

What is direct attachment and indirect attachment? Which is more common?

A

direct attachment - “fleshy” - the attaching strands of CT are so short that the muscle fascicles themselves appear to attach directly to the bone.
indirect attachment - the CT extends well beyond the end of the muscle fibers to form either a cordlike tendon or a flat sheet called an aponeurosis (more common)

86
Q

How large are the largest skeletal muscle cells? (radius and diameter)

A

diameter is up to 100 micrometers and length up to dozens of centimeters in long muscles.

87
Q

What parts would be listed in a labeled diagram of a sarcomere?

A

I band, A band, Z disc, actin, myosin, with heads

88
Q

Where in a skeletal muscle cell is the SR found? What does SR stand for? Describe the functions of the SR.

A

SR = sarcoplasmic reticulum
Function: participate in the regulation of muscle contraction; store large quantities of calcium ions which are released when the muscle is stimulated to contract
Location: surround each myofibril. Most SR tubules run longitudinally along the myofibril. Other SR (terminal cisterns “end sacs”) form larger perpendicular cross channels over the junction between each A band in a myofibril and its adjacent I bands.

89
Q

Where in the skeletal muscle cell are t-tubules found? What does t-tubule stand for? Describe the functions of the t-tubule.

A

t-tubule= transverse tubules
Function: conduct each nerve-generated impulse that travels along the sarcolemma to the deepest regions of the muscle fiber ensuring that the deep-lying myofibrils contract at the same time as the superficial ones.
Location: invaginations of the plasma membrane

90
Q

Describe how a sarcomere shortens during contraction (concentric)

A
  • Calcium ions are released from the sarcoplasmic reticulum
  • Calcium ions bind to regulatory protein which moves and exposes the biding site on actin
  • Myosin binds to actin
  • Power stroke: myosin bends and pulls on actin
  • ATP used to detach and re-cock the myosin head.
91
Q

A neuron that innervate skeletal muscle cells is called a what? How many muscle cells would such a neuron typically innervate? In large muscle groups up to how many would the neuron innervate? how many neurons will innervate a single skeletal muscle cell?

A

motor neuron
typically - 100
large - 1000-3000
single - 4

92
Q

Define the term “motor unit” Give examples of muscle that would have large motor units. Give examples of muscles that would have small motor units.

A

Motor unit - a motor neuron and all the muscle fibers it innervates
Large motor units - hip muscles
small motor units - eyes and fingers

93
Q

What are the characteristics of slow oxidative muscle fibers? Which muscles tend to have more of these fiber types?

A

resistant to fatigue as long as enough oxygen is present, and deliver prolonged contractions, do not generate much power
Many in the postural muscles of the lower back which must contract continuously to keep the spine straight and maintain posture.

94
Q

What are the characteristics of fast glycolytic muscle fibers? Which muscles tend to have more of these fiber types?

A

contract rapidly, tire quickly, and generate much more power than slow oxidative fibers.
Common in the muscles of the upper limbs, which often lift heavy objects for brief periods.

95
Q

What is a muscle fascicle?

A

group/bundle of skeletal muscle cells

96
Q

Where are circular fascicle muscle arrangements found?

A

orbicularis oris muscle around the mouth and the orbicularis oculi around the eyes

97
Q

Where are convergent fascicle muscle arrangements found?

A

pectorals major muscle in the anterior thorax

98
Q

Where are fusiform fascicle muscle arrangements found?

A

Biceps brachii of the arm

99
Q

Where are pennate fascicle muscle arrangements found?

A

deltoid muscle which forms the roundness of the shoulder

100
Q

Explain how the arrangement of fascicles relates to the amount of force a muscle can produce and its range of motion.

A

The more nearly parallel the fibers are to the muscle’s long axis, the more the muscle can shorten, resulting in a larger distance of movement. Although muscles with parallel fascicles can have a greater range of motion, they usually are not powerful. Power depends more on the total number of fibers it contains.

101
Q

What is the most common type of lever system in the body?

A

Third-class lever - muscle attachment is close to joint

102
Q

Explain the advantages and disadvantages of the third-class lever system, and the significance to body movements.

A

Advantage - wide range of motion FAST
Disadvantage - requires more force
- a greater effort is needed to produce a movement, but speed and distance are gained.

103
Q

Define the term “prime mover” as it applies to muscle mechanics. List a joint, a motion, and the prime mover(s) of that motion.

A

Prime mover - main muscle for a particular action; generates much of the force
pectorals major is a prime mover for flexing the arm at the shoulder joint

104
Q

Define the term “antagonist” as it applies to muscle mechanics. List a joint, a motion, and the antagonist(s) of that motion.

A

Antagonist - muscles that opposes the action of a primer mover; reverse the action of a prime mover.
Forearm flexion: biceps brachii and brachialis are prime movers and the triceps brachii is the antagonist.

105
Q

Define the term “synergist” as it applies to muscle mechanics. Synergist can perform multiple functions. Describe each and illustrate the function with an example.

A

Synergist - “helpers”; help the prime movers, either by adding a little extra force to the movement being carried out or (“fixators”) by reducing undesirable extra movements that the prime mover may produce.
Example: synergist of forearm flexion would add a little extra force over part of the range of motion (brachial radialis)
Example: muscles that flex the fingers cross both the wrist and the finger joints but you can make a fist without flexing your wrist because synergists stabilize the wrist.
Example: muscles that fix the scapula when the arm moves.

106
Q

List the criteria used in naming muscles.

A
  1. location
  2. shape
  3. relative size
  4. direction of fascicles
  5. location of attachments
  6. head number
  7. actions

Anatomy (6 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions