Quiz 2 (Modules 6-10) Flashcards
(185 cards)
1
Q
Long bone parts
A
Diaphysis (shaft/body)
Epiphyses (ends)
Epiphyseal (growth) plate
Articular cartilage
Periosteum (surrounds bone surface)
Medullary cavity
Endosteum (lines the medullary cavity)
2
Q
Sharpey’s (perforating) fibers
A
Thick bundles of collagen that extend from the periosteum into the bone extracellular matrix
Attaches periosteum to underlying bone
3
Q
Hydroxyapatite
A
Crystals formed from calcium phosphate and calcium hydroxide in the bones
4
Q
Calcification
A
Mineral salts are deposited in the framework formed by collagen in the extracellular matrix, where they crystallize and the tissue hardens Initiated by osteoblasts
5
Q
Bone’s hardness depends on
A
crystallized inorganic mineral salts
6
Q
Bone’s flexibility depends on
A
its collagen fibers
7
Q
Tensile strength
A
Resistance to being stretched or pulled apart
8
Q
4 types of cells present in bone tissue
A
Osteogenic cells
Osteoblasts
Osteocytes
Osteoclasts
9
Q
Osteogenic cells
A
Unspecialized bone stem cells derived from mesenchyme
Only bone cells to undergo cell division
Found along the inner portion of the periosteum, in the endosteum, and in canals within bone that contain blood vessels
10
Q
Osteoblasts
A
Bone-building cells
Synthesize and secrete collagen fibers and components for extracellular matrix of bone tissue
Initiate calcification
Turn into osteocytes
11
Q
Osteocytes
A
Mature bone cells, main cells in bone tissue
Maintain daily metabolism, eg. exchange of nutrients and wastes with blood
12
Q
Ostoclasts
A
“Carves out bone” - releases enzymes and acid that digest components of the extracellular bone matrix
Huge cells derived from fusion of monocytes
Concentrated in endosteum
Ruffled border on side of cell that faces bone surface
13
Q
Resorption
A
Breakdown of bone extracellular matrix by osteoclasts
Helps regulate blood calcium level
14
Q
Osteon (Haversian system)
A
Repeating structural units of compact bone tissue
Consists of concentric lamellae arranged around a small network of blood vessels, lymphatics, and nerves located in the central (haversian) canal
15
Q
Lamellae
A
Circular plates of mineralized extracellular matrix
16
Q
Lacunae
A
Located between the concentric lamellae
Small spaces which contain osteocytes
17
Q
Canaliculi
A
Interconnecting channels that join lacunae with each other and to nearby blood vessels
18
Q
Concentric vs. Interstitial lamellae
A
Concentric lamellae are found within osteons, interstitial lamellae are found between neighbouring osteons
19
Q
Volkmann’s canals / Perforating canals
A
Transverse canals that allow blood vessels, lymphatic vessels, and nerves from the periosteum to penetrate the compact bone and connect with vessels and nerves of the medullary cavity, periosteum, and central canals
20
Q
Function of compact bone tissue
A
Provides protection and support
Resists the stresses produced by weight and movement
80% of the skeleton, strongest form of bone tissue
21
Q
Function of spongy bone tissue
A
Reduces overall weight of a bone
Support and protect bone marrow
20% of the skeleton, always covered by compact bone
22
Q
4 situations in which bone formation occurs
A
Initial formation of bones in embryo and fetus
Growth of bones until adult sizes are reached
Remodeling of bone (replacement of old bone by new)
Repair of fractures
23
Q
Where yellow bone marrow is contained
A
In the medullary cavity
24
Q
2 methods of bone formation
A
Intramembranous ossification
Endochondral ossification
25
Steps in intramembranous ossification
1. Mesenchymal cells cluster together and differentiate into osteogenic cells then osteoblasts. Osteoblasts secrete extracellular matrix of bone until they are surrounded by it
2. Calcification
3. Formation of trabeculae and development of the periosteum
26
Steps in endochondral ossification
1. Mesenchymal cells crowd together and develop into chondroblasts, which produce hyaline cartilage covered by a perichondrium.
2. Growth of the cartilage model
3. Primary ossification
4. Development of the medullary cavity
5. Secondary ossification
6. Formation of articulate cartilage and the epiphyseal (growth) plate
27
4 zones of the epiphyseal growth plate
Zone of resting cartilage
Zone of proliferating cartilage
Zone of hypertrophic cartilage
Zone of calcified cartilage
28
Appositional growth
Outward expansion - growth in thickness/diameter
Osteoblasts in periosteum form compact bone around external bone surface
Osteoclasts in the endosteum break down bone on the internal bone surface (around medullary cavity)
29
Wolff's law
A bone grows or remodels in response to the forces or demands placed upon it
30
Bone remodeling
Balanced bone deposit and removal
31
Steps in fracture repair
Hematoma formation
Fibrocartilaginous callus formation
Bony callus formation
Bone remodelling
32
Why is the healing process of fractured bone slow?
Bone cell reproduction is normally a slow process
Blood supply has been interrupted
33
Compound fracture
Bone protrudes through the skin
34
Simple fracture
Bone does not protrude through the skin
35
Transverse fracture
Broken at right angles to the long axis of the bone
36
Comminuted fracture
Bone is crushed into small pieces
37
Bones in the axial skeleton
80 bones
Skull
Hyoid
Vertebral column
Sternum
Ribs
38
Bones in the appendicular skeleton
126 bones
Clavicle
Scapula
Upper and lower limbs
Pelvic girdle
39
Number of bones in the adult human body
206
40
5 main types of bones
Long
Short
Flat
Irregular
Sesamoid
41
Long bones
Long shaft
Composed mostly of compact bone with some spongy bone
Function in structural support for the limbs
42
Short bones
Roughly cube-shaped
Composed mostly of spongy bone
43
Flat bones
Thin and plate-like
A thin layer of compact bone surrounding a layer of spongy bone
Often curved
Eg. Skull, rubs, sternum
44
Irregular bones
Varied shapes that don't fit into the other categories
Eg. Vertebrae, hip bones
45
Cranial bones
8
Frontal bone
2 parietal bones
2 temporal bones
Occipital bone
Sphenoid bone
Ethmoid bone
46
Facial bones
14
2 nasal bones
2 maxillae
2 zygomatic bones
Mandible
2 lacrimal bones
2 palatine bones
2 inferior nasal conchae
Comer
47
Hyaline cartilage
Composed of collagen fibers with a flexible matrix
Covers the ends of bones at joints
48
Fibrocartilage
Holds its shape under high compression
Found in between the vertebrae (vertebral discs)
49
Elastic cartilage
Stretchy
Provides support for flexible structures such as the external ear
50
26 vertebrae
7 cervical
12 thoracic
5 lumbar
1 sacrum
1 coccyx
51
Lordosis
Increase in the lumbar curve
52
Normal curvatures of the spine
Primary - thoracic and sacral curves; present before birth
Secondary - cervical and lumbar curves; develop after birth
53
Intervertebral discs - components
Outer fibrous ring - annulus fibrosis
Inner soft, pulpy elastic substance - nucleus pulposus
54
Parts of a vertebra
Vertebral body
Vertebral arch
2 transverse processes, 1 spinous process, 2 superior articular processes, 2 inferior articular processes
55
Parts of the sternum
Manubrium (superior)
Body
Xiphoid process (inferior)
56
Kyphosis
"Hunchback"
Increase in the thoracic curve
57
Components of the shoulder girdle
Clavicle and scapula
58
Glenohumeral joint
Where the scapula articulates with the humerus (shoulder joint)
59
Parts of the hip bones
Ilium
Pubis
Ischium
60
Acetabulum
The socket for the head of the femur
Where the three parts of the hip bone converge
61
Fibrous joints
No synovial cavity
Composed of dense irregular connective tissue
Allow very little movement
Eg. Skull sutures
62
Cartilaginous joints
No synovial cavity
Composed of cartilage
Allow very little or no movement
63
Difference between ligaments and tendons
Ligaments connect bone to bone
Tendons connect muscle to bone
64
Synarthrosis
Immovable joint
65
Amphiarthrosis
Slightly movable joint
66
Diarthrosis
Freely movable joint
All diarthroses are synovial joints
67
Synostosis
Bony joint
A joint in which there is a complete fusion of two separate bones into one
68
Gomphosis
Type of fibrous joint
Where a tooth fits into its socket
69
3 types of fibrous joints
Sutures
Syndesmoses
Interosseous membranes
70
Ligament
Parallel bundles of dense regular connective tissue in a fibrous membrane that are highly adapted for resisting strains
Connects bone to bone
71
6 categories of synovial joints based on movement
Plane
Hinge
Pivot
Condyloid
Saddle
Ball-and-socket
72
Type of joint between the wrist and the thumb
Saddle joint
73
Movements at synovial joints - 4 categories
Gliding
Angular movements
Rotation
Special movements
74
Functions of muscle
Producing body movements
Stabilizing body positions
Storing and moving substances within the body
Generating heat
75
4 special properties of muscular tissue
Electrical excitability
Contractility
Extensibility
Elasticity
76
Contractility
The ability of muscular tissue to contract forcefully when stimulated by an action potential
77
Extensibility
The ability of muscular tissue to stretch, within limits, without being damaged
78
3 layers of connective tissue in skeletal muscle
Epimysium (outermost, encircles the entire muscle)
Perimysium (surrounds fascicles)
Endomysium (inside of each fascicle, separates individual muscle fibers)
79
Fascicle
Bundles of 10-100+ muscle fibers
80
Tendon
Attaches a muscle to the periosteum of a bone
81
Somatic motor neurons
The neurons that stimulate skeletal muscle to contract
Axon typically branches many times
82
Sarcolemma
Plasma membrane of a muscle cell
83
Sarcoplasm
Cytoplasm of a muscle cell
84
Myoglobin
Protein, found only in muscle, that binds oxygen molecules that diffuse into muscle fibers from interstitial fluid
85
5 levels of organization within a skeletal muscle
Skeletal muscle
Fascicle
Muscle fiber (cell)
Myofibril
Filaments (myofilaments)
86
Transverse tubules (T tubules)
Invaginations of the sarcolemma
87
Sarcoplasmic reticulum (SR)
Fluid-filled system of membranous sacs encircling each myofibril In a relaxed muscle fiber, the SR stores calcium ions
88
Terminal cisterns
Dilated end sacs of the SR that are on either side of a transverse tubule
Releases calcium ions from the SR
89
Thin filaments
Composed mostly of actin
Directly involved in the contractile process
90
Thick filaments
Composed mostly of myosin
Directly involved in the contractile process
91
Sarcomere
Basic functional unit of a myofibril
Separated by Z-discs
92
Z disc
Narrow, plate-shapes regions of dense protein material
Separate one sarcomere from the next
93
A band
Portion of a sarcomere
Extends the entire length of the thick filaments
94
I band
Portion of a sarcomere
Lighter, less dense area
Contains thin filaments but no thick filaments
Z disc passes through the centre of the I band
95
H zone
Narrow area in the centre of each A band that contains thick but not thin filaments
96
M line
Middle of the sarcomere
Supporting proteins that hold thick filaments together at the centre of the H zone
97
3 kinds of proteins that make up myofibrils
Contractile proteins
Regulatory proteins
Structural proteins
98
2 contractile proteins in muscle
Myosin and actin
99
2 regulatory proteins in muscle
Tropomyosin and troponin
100
Sliding filament mechanism
Muscle contraction occurs because myosin heads attach to and "walk" along the thin filaments at both ends of a sarcomere, progressively pulling the thin filaments toward the M line
Result - each sarcomere is shortened, which leads to shortening of the entire muscle
101
Onset of contraction
SR releases calcium ions into the sarcoplasm, where they bind to troponin. Troponin moves tropomyosin away from the myosin-binding sites of actin. Then the contraction cycle can begin
102
Contraction cycle - 4 steps
ATP hydrolysis
Attachment of myosin to actin to form cross-bridges
Power stroke
Detachment of myosin from actin
103
Effect of calcium concentration on muscle contraction
Increase in Ca2+ starts muscle contraction
Decrease stops it
104
In the process of muscle contraction, calcium bonds to
Troponin
105
Isometric contraction
When the muscle contracts but does not shorten and does not produce movement
106
All-or-none principle of muscle contraction
Once a minimum threshold is reached the muscle fiber will contract fully
107
Origin of a muscle
The end that attaches to a stationary bone
108
Motor unit
A motor neuron and all the muscle fibers innervated by it
109
A motor neuron and all the muscle fibers innervated by it are called:
Motor unit
110
Muscle tone
Skeletal and smooth muscle remain in a state of continual, partial contraction
111
Insertion
Point of attachment to a moveable bone
112
Prime mover
Main muscle providing force for producing specific movement
113
During anaerobic respiration:
There is an absence of oxygen
Glucose is broken down producing lactic acid and 2 ATP molecules
Energy is provided for 30-40 seconds of strenuous muscle activity
114
Ganglia
Small masses of nervous tissue, consisting primarily of neuron cell bodies, that are located outside of the brain and spinal cord
115
Enteric plexuses
Extensive networks of neurons located in the walls of organs of the GI tract
116
Somatic nervous system (SNS)
Consists of sensory neurons that convey information from somatic receptors in the head, body wall, and limbs and from receptors for the special senses of vision, heating, taste and smell to the CNS, and motor neurons that conduct impulses from the CNS to skeletal muscles only.
Voluntary
117
Autonomic nervous system (ANS)
Consists of sensory neurons that convey information from autonomic sensory receptors to the CNS, and motor neurons that conduct nerve impulses from the CNS to smooth muscle, cardiac muscle, and glands
Involuntary
Two branches - sympathetic and parasympathetic
118
Sympathetic division of the autonomic nervous system
Generally helps support exercise of emergency actions
"Fight-or-flight"
119
Parasympathetic division of the autonomic nervous system
Generally takes care of "rest-and-digest" activities
120
Enteric nervous system
"Brain of the gut"
Involuntary
Muscles of GI tract
121
Functions of the nervous system
Sensory
Integrative (processing)
Motor
122
What organelles do neurons not have
centrioles (this is why neurons cannot replicate themselves; centrioles are needed for mitosis to take place)
123
Lipofuscin
A pigment that occurs as clumps of yellowish brown granules in the cytoplasm, present in aging neurons
124
Nerve fiber
General term for any neuronal extension that emerges from the cell body of a neuron (dendrites and axon)
125
Dendrites
The receiving or input portions of a neuron
126
Axon
Long, thin, cylindrical projection from the cell body
Propagates nerve impulses toward another neuron, a muscle fiber, or a gland cell
127
Neuroglia
Type of cell in nervous tissue
Smaller than neurons
Do not conduct nerve impulses
Support, nourish, and protect neurons
Capable of mitosis
128
Axon hillock
Cone-shaped elevation where the axon connects to the cell body of a neuron
129
Collaterals
Side branches of an axon
130
Multipolar neurons
Have several dendrites and one axon
All motor neurons
131
Bipolar neurons
One main dendrite and one axon
132
Unipolar neurons
Have dendrites and one axon that are fused together to form a continuous process that emerges from the cell body
133
Nissl bodies
Unique to neurons
Specialized layers of rough endoplasmic reticulum that synthesize neurofibrils and microtubules
134
Axon terminals (synaptic knobs)
Ends of the axon
Store neurotransmitters
135
Interneurons / Association neurons
Lie entirely within the central nervous system
Receive input from sensory (afferent) neurons and communicate with one another or with motor (efferent) neurons
136
The type of neuroglia responsible for generating the myelin sheath in the PNS is
Schwann cells
137
The type of neuroglia responsible for generating the myelin sheath in the CNS is
oligodendrocytes
138
Nodes of Ranvier
Gaps in the myelin sheath
139
Nerve
A bundle of nerve cell fibers (axons and dendrites) that follow the same path
Only found in the PNS
140
Tract
Bundle of nerve cell fibers
Found only in the CNS
141
Difference between tracts and nerves
Tracts are bundles of axons in the CNS, nerves are bundles of axons in the PNS
142
Ganglia
Clusters of neuron cell bodies
Found only in the PNS
143
Nuclei (nervous system)
Clusters of neuron cell bodies (one cluster is called a nucleus)
Found only in the CNS
144
Difference between ganglia and nuclei in the nervous system
Ganglia are clusters of neuron cell bodies in the PNS, nuclei are clusters of neuron cell bodies in the CNS
145
Blood-brain barrier
* Protective barrier that keeps harmful substances out of the brain
* Astrocytes form a wall around the outside of the blood vessels
* This astrocytic wall, plus the walls of the blood vessels, is collectively called the blood-brain barrier
146
Significance of the blood-brain barrier
Drugs (e.g., penicillin) that are needed to treat disorders in other parts of the body have no effect in the brain because they are not able to cross the blood-brain barrier
147
When the membrane is at the resting membrane potential
1) There is an unequal distribution of sodium ions at the inner and outer surface of the membrane
2) The membrane potential is approximately -70mV
3) The membrane is more permeable to the diffusion of potassium ions than sodium ions
148
4 types of ion channels in neurons
Leak channels
Ligand-gated channel
Mechanically gated channel
Voltage-gated channel
149
Resting membrane potential of a neuron
-70 mV
150
3 major factors that cause resting membrane potential
Unequal distribution of ions in the ECF and cytosol
Inability of most anions to leave the cell
Electrogenic nature of the Na+/K+ ATPases
151
Graded potential
Small deviation from the membrane potential
Occurs when a stimulus causes gated channels to open or close in an excitable cell's plasma membrane
Disperses over a short distance
Occur mostly in the dendrites and cell body of a neuron
152
Decremental conduction
Mode of travel by which graded potentials die out as they spread along the membrane
153
Summation
The process by which graded potentials add together
154
Action potential
A rapid change in the membrane potential along a nerve fiber
155
Depolarizing phase
Negative membrane potential becomes less negative, reaches zero, then becomes positive
156
Repolarizing phase
Membrane potential is restored to the resting state of -70mV
157
After-hyperpolarizing phase
Memrane potential temporarily becomes more negative than the resting level
158
Absolute refractory period
Even a very strong stimulus cannot initiate a second action potential
159
Relative refractory period
Period of time during which a second action potential can be initiated but only by a larger-than-normal stimulus
160
Continuous conduction
Involves step-by-step depolarization and repolarization of each adjacent segment of the plasma membrane
Occurs in unmyelinated axons and muscle fibers
161
Saltatory conduction
Occurs along myelinated axons
Action potential appears to "leap" from node to node
Much faster and energy-efficient (less ATP used)
162
Factors that affect the speed of propagation of action potentials
1. Amount of myelination
2. Axon diameter (larger diameter -\> faster)
3. Temperature (lower temp -\> slower)
163
Axodendritic synapse
From axon to dendrite
164
Axosomatic synapse
From axon to cell body
165
Axoaxonic synapse
From axon to axon
166
Electrical synapse
Action potentials conduct directly between the plasma membranes of adjacent neurons through structures called gap junctions
167
Advantages of electrical synapses
Faster communication Synchronization
168
Acetylcholine (ACh)
The only neurotransmitter that is released at the synapses between neurons and skeletal muscle cells (i.e., at the neuromuscular junction– NMJ)
169
Meninges
3 protective connective tissue coverings that encircle the spinal cord and brain Dura mater Arachnoid mater Pia mater
170
Epidural space
A space between the dura mater and the wall of the vertebral canal Contains a fat and connective tissue that protect the spinal cord
171
Subdural space
Between the dura mater and the arachnoid mater Contains interstitial fluid
172
Denticulate ligaments
Extensions of the pia mater that suspend the spinal cord in the middle of its dural sheath Protect the spinal cord against sudden displacement
173
Subarachnoid space
Between the arachnoid mater and the pia mater Contains CSF
174
Endoneurium
Innermost layer of connective tissue that wraps around individual axons (and their myelin sheaths if present) in a nerve
175
Perineurium
Layer of connective tissue surrounding a fascicle (bundle of axons)
176
Epineurium
Outermost covering over the entire nerve
177
The innermost meninx adhering to the brain and spinal cord
Pia mater
178
4 main regions of the brain
Cerebrum, diencephalon, brain stem, cerebellum
179
Frontal lobes
• Movements of voluntary skeletal muscles • Higher intellectual processes such as concentration, planning, and problem solving
180
Parietal lobes
• Sensations of temperature, touch, pressure, and pain • Understanding speech and using words
181
Temporal lobes
• Hearing and smelling • Memory of scenes and music
182
Occipital lobes
• Vision • Combining
183
Corpus colossum
connects the two hemispheres and provides the communication pathway between the two halves
184
4 ventricles of the brain
fluid-filled cavities - two lateral ventricles, the third ventricle, and the fourth ventricle
185
Cerebrospinal fluid is produced by the
Choroid plexus
