ch. 38 Flashcards
(126 cards)
1
Q
what is abduction?
A
when a bone moves away from the midline of the body
2
Q
What is acetylcholinesterase(AchE)? what does it do?
A
an enzyme that breaks down ACh into acetyl and choline
3
Q
what is actin?
A
globular contractile protein
4
Q
what do myosin and actin work together to produce?
A
muscle contractions
5
Q
what is adduction?
A
movement of the limbs inward after abduction
6
Q
what is amphiarthorosis? what does it include?
A
a joint that allows slight movement; includes syndesmoses and symphyses
7
Q
when is angular movement produced?
A
when the angle between the bones of a joint change
8
Q
what is an appendicular skeleton composed of?
A
it is composed of the bones of the upper limbs and the lower limbs
9
Q
what is the function of the bones of the upper limbs in an appendicular skeleton?
A
they function to grasp and manipulate objects
10
Q
what do the bones of the upper limbs permit in an appendicular skeleton?
A
they permit locomotion
11
Q
what happens during appositional growth?
A
an increase in the diameter of bones by the addition of bone tissue at the surface of the bones
12
Q
what is an articulation?
A
any place where two bones are joined
13
Q
what does an auditory ossicle do?
A
transducers sounds from the air into vibrations in the fluid-filled cochlea
14
Q
what is a hydrostatic skeleton?
A
skeleton that consists of aqueous fluid held under pressure in a closed body compartment (soft-bodied, fluid filled cavity)
15
Q
what terrestrial animals have hydrostatic skeletons?
A
earthworms and slugs
16
Q
what aquatic animals have hydrostatic skeletons?
A
jellyfish and squid
17
Q
what is the advantage of a hydrostatic skeleton?
A
it is flexible
18
Q
what are the disadvantages of a hydrostatic skeleton?
A
drying and squishy
19
Q
what is an exoskeleton?
A
a secreted cellular product external skeleton that consists of a hard encasement on the surface of an organism (ridged hard case and muscles attach internally)
20
Q
what animals have exoskeletons? what makes up the exoskeleton?
A
arthropods; chitin
21
Q
what are the advantages of an exoskeleton?
A
can resist desiccation and good for protection
22
Q
what are the disadvantages of an exoskeleton?
A
must molt in order to grow, weighs more, and are vulnerable to predation
23
Q
what animals have endoskeletons?
A
echinoderms and vertebrates
24
Q
what makes up a vertebrate’s endoskeleton?
A
calcium phosphate (Ca3[PO4]2)
25
what makes up a echinoderm’s endoskeleton?
calcium carbonate (CaCO3)
26
what is an endoskeleton?
skeleton of living cells that produces a hard, mineralized tissue located within the soft tissue of organisms
27
what is the purpose of cartilage in an endoskeleton?
joint movement
28
what is the purpose of ligaments in an endoskeleton?
joint stability
29
what is the purpose of tendons in an endoskeleton?
muscle attachment
30
what are the four functions of an endoskeleton?
1. protection’
2. muscle attachment
3. living tissue
4. mineral storage
31
what minerals does an exoskeleton store?
calcium and phosphate
32
what does the endoskeleton protect?
organs (heart/lungs)
33
what is the function of the living tissue of an endoskeleton?
to produce red/white blood cells and remodel from stress
34
What are the bones of the central axis?
- skull (w/ cranial bones) (including mandible and maxilla)
- sternum
- rib cage
35
what are the functions of the vertebral column (aka spine)?
surrounds and protects the spinal cord, supports the head, and acts as an attachment point for ribs and muscles of the back and neck
36
how many cervical vertebrae are there in the vertebral column?
7
37
how many thoracic vertebrae are there in the vertebral column?
12
38
how many sacral vertebrae are there in the vertebral column?
5 fused
39
how many coccyx vertebrae are there in the vertebral column?
4 fused
40
what types of vertebrae in the vertebral column are fused?
sacral and coccyx
41
what are the bones of the human limbs?
the pectoral girdle and the pelvic girdle
42
what is the function of the pectoral girdle?
attaches the upper limbs to the body
43
what is the function of the pelvic girdle?
attaches the lower limbs to the body
44
what bones make up the pectoral girdle?
scapula and clavicle
45
what bones make up the pelvic girdle?
ilium, ischium, and pubis
46
what bones make up the forelimb?
humerus, ulna, radius, carpels, metacarpals, and phalanges
47
what bones make up the hindlimb?
femur, patella, tibia, fibula, tarsals, metatarsals, and phalanges
48
when is a bone considered a “long bone”?
when the length is greater than the width
49
what is the structure of a long bone?
a shaft (diaphysis) with two ends (epiphyses)
50
what characterizes short bones?
they are cuboidal and their length is equal to width
51
examples of long bones?
humerus and femur
52
examples of short bones?
carpels and tarsals
53
what are characteristics of flat bones?
- thin and broad
- used for organ protection
54
what are some examples of flat bones?
sternum and ribs
55
what is a characteristic of irregular bones?
complex shapes
56
what are examples of irregular bones?
vertebrae and hip bones
57
what are characteristics of sesamoid bones?
small and flat
58
what are characteristics of sutural bones?
irregular, small, and flat
59
what is an example of a sesamoid bone?
patellae
60
what are examples of sutural bones?
bones of the skull
61
what are bones?
organs; collections of tissue
62
what does a compact bone form?
forms the hard external layer of all bones
63
what is another name for contact bone?
cortical bone
64
what is another name for spongy bone?
cancellous bone
65
what does spongy bone lack?
osteons
66
what cells does spongy bone form?
blood cells
67
what surrounds the medullary cavity?
compact bone
68
what is spongy bone?
is forms the inner layer of all bones
69
what are trabeculae?
lamellae that are arranged as rods or plates
70
what do osteoblasts secrete? for what?
they secrete the matrix for bone formation
71
what do osteoclasts do?
breakdown bone matrix
72
what are osteoclasts?
large bone cells with up to 50 nuclei (multinucleate cells derived from WBCs), responsible for bone remodeling
73
what activates osteoclasts?
PTH (parathyroid hormone)
74
what is an osteoblast?
bone cell responsible for bone formation
75
what are osteocytes?
mature bone cells and the main cell in bone tissue; trapped osteoblasts; living bone cells
76
what are lacunae?
tight spaces in the bones that house osteoblasts (space in cartilage and bone that contains living cells)
77
what are canaliculi?
canals connecting lacunae that allow osteocytes to communicate (microchannel that connects the lacunae and aids diffusion between cells)
78
what is the haversian canal?
central canal in bones that contains the bone’s blood vessels and nerve fibers (contains blood vessels for osteon
79
what is ossification?
(aka osteogenesis) process of bone formation by osteoblasts (not calcification!)
80
what is intramembranous ossification?
process of bone development from fibrous membranes
81
where does intramembranous ossification start and end?
start: mesenchymal cells
end: flat bones, mandible
82
what is endochondral ossification?
process of bone development from hyaline cartilage
83
where does endochondral ossification start and end?
start: chondrocytes
end: all other bones
84
how is a growth hormone disorder treated?
with injections
85
what is the epiphyseal plate (aka growth plate)?
region between the diaphysis and epiphysis that is responsible for the lengthwise growth of long bones
86
what does it mean when the growth plate ossifies?
growth stops
87
what does a chronic low calcium deficiency mean for the bones?
amt of bone calcium decreases while the risk of fractures increases
88
what do bones do when exposed to repeated stress?
they remodel, thickening to prevent fractures
89
what is a fibrous joint?
joint held together by fibrous connective tissue; has no cavity, space, or movement
90
what is an example of a fibrous joint?
sutures of the skull
91
what are syndesmoses joints?
joint in which the bones are connected by a band of connective tissue, allowing for more movement than in a suture (no cavity or space, some movement, amt of movement = length of CT)
92
what are examples of syndesmoses joints?
gomphoses and teeth; tibia and fibia to ankle
93
what is a cartilaginous joint?
joint in which the bones are connected by cartilage (no cavity or space; very little movement)
94
what are synchondroses?
bones joined by hyaline cartilage; found in the epiphyseal plates of growing bones in children
95
what are symphyses?
hyaline cartilage covers the end of the bone, but the connection between bones occurs through fibrocartilage; symphyses are found at the joints between vertebrae
96
what are synovial joints?
only joint that has a space between the adjoining bones; fluid lubricates joint; ends covered with hyaline
97
what are the three types of functional joints?
- synarthrosis (immovable)
- amphiarthroses (slight movement)
- diathroses (free movement)
98
what are the four movement types of functional joints?
- gliding
- angular
- rotational
- special
99
what kind of joint is the atlas-axis (where skull connects to spine)?
pivot
100
what kind of joint is the elbow?
hinge
101
what kind of joint is between the carpals and metacarpals?
saddle
102
what kind of joint is the ankle?
plane
103
what kind of joint is between the radius and carpal bones of the wrist?
candyloid
104
what kind of joint is the hip?
ball and socket
105
what are the three types of muscle?
skeletal, cardiac, and smooth
106
what is skeletal muscle tissue?
forms skeletal muscles, which attach to bones and control locomotion and any movement that can be consciously controlled
107
what are characteristics of skeletal muscle?
voluntary, striated, and multinucleated
108
what are characteristics of cardiac muscle?
self initiating, striated, uninucleate, and only found in the heart
109
what are some characteristics of smooth muscle?
involuntary and makes up the walls of organs
110
what is a sarcomere?
the smallest working subunit of muscular contraction; functional unit of skeletal muscle
111
what is the process of a neuromuscular synapse?
1. acetylcholine released from the axon terminal binds to receptors on the sarcolemma
2. an action potential is generated and travels down the T tubule
3. CA2+ is released from the sarcophagi cell reticulum in response to change in voltage
4. CA2+ binds troponin; cross bridges form between actin and myosin
5. acetylcholinesterase removes acetylcholine from the synaptic cleft
6. CA2+ is transported back into the sarcoplasmic reticulum
7. tropomyosin binds active sites on actin causing the cross-bridge to detach
112
what is the purpose of tropomyosin?
acts to block myosin binding sites on actin molecules, preventing cross-bridge formation and preventing contraction until a muscle receives a neuron signal (found on actin; blocks binding sites)
113
what is the function of troponin?
binds to tropomyosin and helps to position it on the actin molecule, and also binds calcium ions (found on actin and TPM; holds actin and TPM)
114
what does low calcium do to the regulation of muscle contractions?
TPM inhibits cross-bridge, blocks binding site
115
what does high calcium do to the regulation of muscle contractions?
TPN changes confirmation, exposes binding sites
116
what is the sliding filament theory?
that the sliding of microfilaments contracts sarcomeres
117
what is happening in photo 1?
1. CA2+ is released from the sarcoplasmic reticulum
2. CA2+ in the sarcoplasm binds to troponin and exposes myosin-binding sites on the actin filaments
118
what is happening in image 2?
myosin heads bind to actin; release of Pi initiates power stroke
119
what is happening in image 3?
in the power stroke, the myosin head changes conformation; filaments slide past one another (rigor mortis)
120
what is happening at image 4?
ADP is released at the end of the power stroke; ATP binds to myosin causing it to release actin
121
what is happening at image 5?
hydrolysis of ATP returns the myosin head to its “cocked” position
122
what is happening at 6?
if Ca2+ is returned to the sarcoplasmic reticulum, the muscle relaxes
123
what is happening at 7?
if Ca2+ remains available, the cycle repeats and muscle contraction continues
124
what ion is important for releasing neurotransmitters and/or causing muscular contraction?
Ca2+
125
what bone was produced as a result of intramembranous ossification?
mandible
126
_____ secrete the calcium phosphate that secretes the inorganic hydroxyapatite of bone, while _____ chemically breakdown bone to release calcium and phosphate into the blood.
osteoblasts; osteoclasts
