Brainscape's Knowledge GenomeTM

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


See full index

MCAT BIOLOGY FLASHCARDS > MCAT BIO CH. 11 PART 1 > Flashcards

MCAT BIO CH. 11 PART 1 Flashcards

You may prefer our related Brainscape-certified flashcards:
MCAT flashcards AP® Biology flashcards Biology 101 flashcards
1
Q

What are the three types of muscle?

A
  1. Skeletal
  2. Cardiac
  3. Smooth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are tendons?

A

Connect muscles, strong connective tissue formed of collagen

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

What are the four ways skeletal muscles can move?

A
  1. Flexing
  2. Extending
  3. Abducting
  4. Adducting
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What skeletal muscle movement is flexing?

A

Muscles can move a joint by flexing

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

What skeletal muscle movement is extending?

A

Increasing the angle of the joint

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

What skeletal muscle movement is abducting?

A

Moving away from the body’s midline

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

What skeletal muscle movement is adducting?

A

Moving towards the body’s midline

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

What is the only way for bones and joints to move?

A

By contracting skeletal muscles

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

What does it mean when a skeletal muscle has an origin?

A

Point on this bone where the muscle attaches

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

What does it mean when a skeletal muscle has a muscle insertion?

A

Point where the muscle attaches on the bone more distant from the center of the body

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

What are muscles that are antagonistic?

A

Muscles that are responsible for movement in opposite direction

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

What are muscles that are synergistic?

A

Muscles that move a joint in the same direction

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

When antagonistic muscles receive stimulation by neurons, how do they differ between contraction and relaxation?

A

Difference in timing of the signal (frequency) and the amount of neurotransmitter released

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

What are fascicles based on structure of skeletal muscle?

A

Connective tissue that holds the contractile tissue together in bundles to allow flexibility within the muscle

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

What are muscle fibers?

A

Myofibers; single skeletal muscle cell

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

Where are myofibers found?

A

Located within each fascicles bundle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is an important factor of the nucleus of skeletal muscle cells?

A

They are multinucleate syncytia

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

How is the multinucleate syncytia formed in skeletal muscle cells?

A

By the fusion of individual cells during development

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

What is sarcolemma?

A

The myofiber cell membrane

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

What is the sarcolemma made out of?

A

Of plasma membrane and an additional layer of polysaccharide and collagen

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

Why is it important for the myofiber to have sarcolemma?

A

Helps the cell to fuse with tendon fibers

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

What are myofibrils?

A

Smaller myofiber units that generate contractile force of skeletal muscle

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

What are the proteins in the myofibril that generate contraction?

A

Actin and myosin

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

What is the difference between actin and myosin when they polymerize?

A

Actin polymerizes to form thin filaments, myosin forms thick filaments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What is the reason for the striated appearance of the skeletal muscle?

A

Due to the overlapping arrangement of bands of thick and thin filaments in sarcomeres

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

What are the sarcomeres bound by?

A

Z lines

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

How are the sarcomeres aligned and where are they located?

A

End to end, in myofibril

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

Thick filaments are also attached to the Z lines. T/F

A

False: they are not

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

Thin filaments attach to each Z line and overlap with ______ in the middle of each ______?

A

Thick filaments; sarcomere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

What are I bands based on myofibril?

A

Regions of he sarcomere composed only of thin filaments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What are A band based on myofibril?

A

The full length of the thick filament represents the A band within each sarcomere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is the H zone based on myofibril?

A

Region composed of only thick filaments

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

Where is contraction generated based on myofibril structure?

A

Overlapping regions of thick and thin filaments

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

Based on thick and thin filaments, when does contraction occur based on their structure?

A

When the thin and thick filaments slide across each other, drawing the Z lines of each sarcomere closer together

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

During muscle contraction, do thick and thin filaments shorten? What shortens?

A

No they slide across each other; the sarcomere sheens without them changing their lengths

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

Filament sliding requires….?

A

ATP hydrolysis

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

Which protein uses ATP to create movement?

A

Myosin - sometimes also named myosin ATPase

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

Each myosin monomer contains a ___ and a ____?

A

Head and tail

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

The head of the myosin monomer attaches to what?

A

The myosin binding site; a specific site on an actin molecule

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

When myosin and actin are connected, they’re said to be connected by….

A

A crossbridge

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

Contraction occurs when what decreased, based on myosin and actin?

A

When the angle between the head and the tail decreases

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

What is the first step of filament sliding in skeletal muscle?

A

Cross bridge formation; myosin has ADP and Pi bond

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

What is cross bridge formation?

A

Binding of the myosin head to a myosin binding site on actin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

What is the second step of filament sliding in skeletal muscle?

A

Power stroke from myosin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

What is the power stroke from myosin and when does it happen during filament sliding?

A

Myosin head moves to a low energy confirmation and pulls actin chain towards center of sarcomere; ADP is released and during 2nd step

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

What happens during step two then myosin head moves to a low energy confirmation?

A

They pull actin chain towards center of sarcomere

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

In which step of filament sliding does a new ATP molecule binds?

A

Step 3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

What is the third step of filament sliding in skeletal muscle?

A

ATP binding necessary to release actin by the myosin head

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

What is the four step of filament sliding in skeletal muscle?

A

ATP hydrolysis, myosin head cocked formation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

What does is mean when mentioned the myosin heads are cocked?

A

Set in a high-energy conformation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

In the myofiber, contraction only occurs when…?

A

The cytoplasmic Ca2+ increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

Which molecule contains troponin-tropomyosin complex?

A

Thin filaments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

What does troponin-tropomyosin complex?

A

Prevents contraction when Ca2+ is not present

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

What is tropomyosin?

A

A long fibrous protein that winds around the actin polymer, blocking all the myosin-binding sites

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

What is troponin?

A

A globular protein bound to the tropomyosin that can bind Ca2+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

What happens to troponin when it binds to Ca2+?

A

It undergoes conformation change that moves tropomyosin out of the way so that myosin heads can attach to actin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

What protein is responsible for ATP hydrolysis during muscle contraction?

A

Myosin protein with the ATPase activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

What is the neuromuscular junction?

A

The synapse between an axon terminus and a myofiber

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

The neuromuscular junction is a single point. T/F

A

False: A long invagination of the cell membrane - axon terminus is elongated to fill the long synaptic cleft

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

What is the purpose of the neuromuscular junction?

A

Allow the neuron to depolarize a large region of the postsynaptic membrane at once

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

What is the motor end plate?

A

The postsynaptic membrane of the neuromuscular junction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

What is the neurotransmitter as the neuromuscular junction point?

A

ACh acetylcholne

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

During the impulse transmission at the NMJ, an action potential arrives at the axon terminus and triggers the opening of _______ channels?

A

voltage-gated Ca 2+ channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

During the impulse transmission at the NMJ, the resulting increase in ________ triggers the _______ of ACh?

A

Intracellular Ca 2+; release of vesicles of acetylcholine

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

What does the postsynaptic membrane contain to read ACh?

A

Contains ACh receptors which are ligand-gated Na+ channels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

Based on impulse transmission in NMJ, how does ACh reach their receptors?

A

By diffusing across the synaptic cleft

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

What happens when ACh binds to the receptors of the postsynaptic membrane receptors?

A

A postsynaptic sodium influx, which depolarizes the postsynaptic membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
68
Q

What is the end late potential?

A

The depolarization of the postsynaptic membrane when ACh binds to the receptors of the postsynaptic membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
69
Q

What is the miniature EPP?

A

The smallest measurable AP dcaused by exocytosis of a single ACh vesicle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
70
Q

When does ACh stop stimulating postsynaptic receptors?

A

Until it is destroyed by acetylcholinesterase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
71
Q

What are T-tubules?

A

Transverse tubules; deep invaginations of the cell membrane which allow the AP to travel into the thick cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
72
Q

What is the structure of the sarcoplasmic reticulum?

A

A huge, specialized smooth endoplasmic reticulum that enfolded each myofibril in the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
73
Q

What is the SR specialization?

A

Specialized to sequester and release Ca 2+

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
74
Q

How is the calcium removed from the SR?

A

Active transporters remove calcium from the sarcoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
75
Q

What is the sarcoplasm?

A

Myofiber cytoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
76
Q

What happens when the AP travels down the T-tubular network?

A

It depolarizes the cell and the sarcoplasmic reticulum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
77
Q

The sarcoplasmic reticulum contains what? What does it allow?

A

Voltage-gated Ca 2+ channels, allows calcium to rush out of the SR into the sarcoplasm upon depolarization

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
78
Q

When the cell myofiber repolarizes, what happens to the calcium?

A

It is actively sequestered by the SR and contracted is ended

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
79
Q

The smallest measurable muscle contraction is know as….?

A

Muscle twitch

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
80
Q

What are the two ways the nervous system can increase the force of contraction?

A
  1. Motor unit recruitment

2. Frequency summation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
81
Q

What is a motor unit?

A

A group of myofibers innervated by the branches of a single motor neuron’s axon

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
82
Q

What does a muscle twitch result from?

A

The activation of one motor neuron and a larger twitch can be obtained by activating more motor neurons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
83
Q

What is a motor unit recruitment?

A

Activating or recruiting more motor neurons and thus more myofibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
84
Q

When does each contraction ends?

A

When the SR returns calcium to low resting levels

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
85
Q

What is tetanus?

A

Rapidly repeating series of stimulation resulting in the strongest contraction possible

86
Q

The skeletal muscle does not have a refractory period.T/F

A

False: it does

87
Q

What is frequency summation?

A

The second contraction builds on the first as there’s no time for calcium to become sequestered

88
Q

When does frequency summation over through refractory period?

A

Successive stimulation must be greater than the duration of the refractory period

89
Q

What is the length-tension relationship?

A

A muscle contracts more forcefully at an optimum length

90
Q

What is the length of a sarcomere at the muscle contracting at optimum length?

A

2.2 microns

91
Q

What happens at 2.2 microns in sarcomere length based on contraction?

A

A maximum degree of overlap between thick and thin filaments

92
Q

Why is greater sarcomere length favorable compared to shorter length?

A

A shorter length causes filaments to obstruct each other’s movement by bumping together

93
Q

What molecule is used for intermediate-term energy storage in the myofiber?

A

Creatine phosphate

94
Q

What is myoglobin? What is its role?

A

A globular protein; provide an oxygen reserve by taking O2 rom hemoglobin and then releasing it as needed

95
Q

What happens when the supply of oxygen runs low in the myofiber?

A

Metabolism becomes anaerobic and lactic acid is produced

96
Q

When lactic acid is produced, how does it cause a pH drop in the blood?

A

Because it moves into th bloodstream

97
Q

What happens to the lactic acid that infiltrates our blood, how is it removed?

A

The liver picks up this lactate and converts it into pyruvate

98
Q

What is rigor mortis?

A

Rigidity of skeletal muscles which occurs soon after death due to complete ATP exhaustion

99
Q

Skeletal muscle fibers fall into two categories:….

A

Slow twitch fibers and fast twitch fibers

100
Q

What are type I slow twitch fibers known as?

A

Red slow twitch or red oxidative

101
Q

Why are they called red oxidative or red slow twitch fibers?

A

Because of their high myoglobin content

102
Q

Why do red oxidative have much better blood supply than fast twitch fibers?

A

Extensive surrounding capillary network

103
Q

What allows slow twitch fibers to maintain contraction for extended periods of time?

A

Good oxygen delivery and ability to store oxygen in myoglobin

104
Q

Why does Type IIA fast twitch fibers has more fatigue resistant than Type II B?

A

Have more mitochondria

105
Q

What are Type IIA known as?

A

Fast twitch oxidative fibers

106
Q

What type of force does Type IIB fast twitch fibers provide?

A

Explosive force needed

107
Q

What is different between the skeletal muscle maximum length and the cardiac muscle maximum length?

A

Cardiac muscle has no such limitations

108
Q

What is different between the structure of skeletal and cardiac muscle?

A

Skeletal muscles are syncytial and cardiacs are not, they each only have one nucleus

109
Q

All the muscle cells in the cardiac muscle are interconnected with what?

A

By gap junctions known as intercalated disks

110
Q

What do the intercalated disks in the cardiac muscle allow?

A

Allow AP to propagate throughout the entire heart without allowing nuclei and cytoplasmic contents to be shared

111
Q

What is heart muscle called based on the function of their intercalated discs?

A

Functional syncytium

112
Q

What is different between the calcium content between skeletal and cardiac muscle?

A

Skeletal muscle calcium comes for SR intracellular structure, cardiac muscle requires some from extracellular environment

113
Q

If neurons don’t trigger cardiac contraction, what does?

A

Pacing by the sinoatrial node

114
Q

Which muscle does not depend on stimulation by motor neurons?

A

Cardiac muscles

115
Q

The vagus nerve release ACH for heart muscle at chemical synapses with the heart is….?

A

Inhibitory

116
Q

What type of channels is the AP in cardiac muscles dependent on?

A

Na and Ca channels

117
Q

What are sodium channels in the cardiac muscles called? What about calcium channels?

A

Sodium: fast channels Calcium: slow channels

118
Q

Why are calcium channels in cardiac muscles called slow channels?

A

They respond more slowly to threshold depolarization

119
Q

What does the voltage-gated calcium channel in cardiac muscle cause the cardiac AP to have?

A

Plateau

120
Q

What is the significance of the plateau phase in cardiac muscle?

A
  1. Longer duration of contraction

2. Longer refractory period to prevent disorganized impulses

121
Q

Smooth muscles have T-tubules. T/F

A

False: they’re too small

122
Q

Smooth muscles are narrower and shorter than skeletal muscles. T/F

A

True

123
Q

How many nucleus do smooth muscle cells have? How is it connected to its neighbors?

A

One nucleus; by gap junctions

124
Q

Why does the cell appear smooth and not striated in smooth muscle cells?

A

Thick and thin filaments not organized into sarcomeres in smooth muscle

125
Q

What molecules control contraction in smooth muscle cells?

A

Calmodulin and myosin light-chain kinase

126
Q

What does calmodulin do and what does myosin light-chain kinase do?

A

Binds Ca 2+ and activates MLCK, MLCK then phosphorylates a portion of the myosin molecule

127
Q

What is different with the calcium storage of smooth and skeletal muscle?

A

Smooth muscle also relies on extracellular calcium

128
Q

What does the smooth muscle cell action potential vary on?

A

Depending on the location of the smooth muscles

129
Q

How do smooth muscles cells sometimes sustain prolonged contractions?

A

Has action potentials similar to those of cardiac muscle, although with a less sharp spike

130
Q

How are the resting potentials of smooth muscle cells?

A

Fluctuating

131
Q

The fluctuations in resting potentials are called what and due to what?

A

Called slow waves; ion pass through the gap junctions between neighboring cells, causing the changes in resting potential to propagate like waves

132
Q

What are slow waves necessary for based on smooth muscle cells?

A

Coordinate the action potentials

133
Q

How are the amplitudes of slow waves passing through smooth muscle cells altered?

A

Increased by ACh, decreased by NE

134
Q

How do the motor neurons differ between smooth muscle cells and skeletal muscle cells?

A

Smooth: autonomic motor neurons while skeletal have somatic motor neurons

135
Q

How does the action potential differ between smooth, skeletal and cardiac?

A

Skeletal: Each AP limited to one large myofiber
Cardiac: One large function syncytium
Smooth: Spreads from cell to cell; shares features of bot

136
Q

What does the skeletal system synthesize and what is it called?

A

The elements ht blood; hematopoiesis

137
Q

What are the axial components of the skeleton? What are the appendicular?

A

Axial: Skull, vertebral column and rib cage
Appendicular: all other bones

138
Q

What are connective tissues derived from?

A

Fibroblast, progenitor

139
Q

What are two important fibrous protein?

A

Collage, elastin

140
Q

What are three important fibroblast cells?

A

Adipocytes (fat cells), Chondrocytes (Cartilage cells), Osteocytes (Bone cells)

141
Q

Why does connective tissue differ from other tissue types in the body?

A

Primarily extracellular material wit few cells scattered in it

142
Q

What is the matrix based on connective tissue?

A

Extracellular material

143
Q

What are ground substance based on connective tissue?

A

Fibers in connective tissue, thick viscous material

144
Q

What are the main ingredients of the ground substance in connective tissue?

A

Proteoglycans

145
Q

What are proteoglycans?

A

Large macropolymers consisting of protein core with many attached carbohydrate chains in connective tissue

146
Q

What are glycosaminoglycans?

A

Carbohydrate chains that attach proteoglycans in connective tissue

147
Q

What gives connective tissues their thickness and firmness?

A

The carbohydrate chains of the connective tissue are hydrophilic

148
Q

What are the two types of connective tissue?

A
  1. Loose

2. Dense

149
Q

What is loose connective tissue?

A

Packing tissues including areolar tissue and adipose tissue

150
Q

What is areolar tissue and what is adipose tissue?

A

Areolar: Soft material between cells Adipose: Fat tissue

151
Q

What is dense connective tissue?

A

Tissues that contain large amounts of fibers

152
Q

What are the two types of bone shapes?

A

Flat and long

153
Q

What are flat bones mostly used for?

A

Protection of organs

154
Q

What are long bones used for?

A

Support and movement

155
Q

What is a diaphysis? What about. an epiphysis?

A

Main shaft of a long bone; flared end

156
Q

What are the two general structures of a bone?

A

Compact or spongy

157
Q

How are compact bones based on structure? What about spongy?

A

Compact: hard and dense
Spongy: Porous

158
Q

Where are spongy bones always found?

A

Surrounded by a layer of compact bone

159
Q

What are the three different types of marrows?

A
  1. Bone marrows
  2. Yellow marrow
  3. Red marrow
160
Q

What is bone marrow?

A

Non-bony material found int he shafts of long bones and pores of spongy bones

161
Q

What is red marrow?

A

Found in spongy bone within flat bones and is the site of hematopoiesis

162
Q

What is yellow marrow?

A

Found in the shafts of long bones filled with fat and is inactive

163
Q

Bones are composed of two principal ingredients, what are they?

A
  1. Collagen

2. Hydroxyapatite

164
Q

What is hydroxyapatite?

A

Solid material consisting of calcium phosphate crystals

165
Q

What characteristic does hydroxyapatite provide for bone structures?

A

strength and inflexibility

166
Q

What are spicules or trabeculae?

A

Spikes of bone in spongy

167
Q

What is an osteon?

A

The basic unit of compact bone structure

168
Q

What is the osteon sometimes referred to?

A

Haversian system

169
Q

What is the central canal of the osteon?

A

A hole which contains blood, lymph vessels and nerves

170
Q

What are lamellae in compact bones?

A

Surrounding the cancel, concentric rings of bone

171
Q

What is the canaliculi of compact bones? What about the lacunae?

A

Tiny channels; spaces

172
Q

Where are osteocytes located and what are they?

A

In each lacuna; mature bone cell

173
Q

Why do osteocytes have long processes that extend down the canaliculi?

A

To contact other osteocytes through gap junctions allowing cells to exchange nutrients and waste

174
Q

What are perforating or volkmann’s canals?

A

Channels that run perpendicular to central canals to connect osteons

175
Q

What is cartilage?

A

A strong, flexible extrcellular tissue

176
Q

What is cartilage secrete by?

A

Chondrocytes

177
Q

What are the three types of cartilage?

A

Hyaline, elastic and fibrous

178
Q

What is hyaline cartilage and found where?

A

Strong and somewhat flexible; found in larynx and trachea

179
Q

What is elastic cartilage?

A

Contains elastin; found in areas that require support and more flexibility - outer ear and epiglottis

180
Q

What is articular cartilage?

A

Joints lined by hyaline cartilage

181
Q

What is fibrous cartilage?

A

Rigid and found in places where very wrong support is needed

182
Q

What does avascular mean? Which component the body is that?

A

No blood vessels; cartilage

183
Q

How does cartilage receive nutrition and immunity since its avascular?

A

From surrounding fluid

184
Q

What is the difference between ligaments and tendons?

A

Ligaments connect bones to other bones, tendons connect bones to muscles

185
Q

What are synarthroses joints?

A

Immovable joints

186
Q

What are amphiarthroses joints?

A

Slightly movable joints

187
Q

Wha are diarthroses joints?

A

Freely movable joints

188
Q

What are Immovable joints called?

A

synarthroses

189
Q

What are Slightly movable joints called?

A

amphiarthroses

190
Q

What are Freely movable joints called?

A

diarthroses

191
Q

What is synovial fluid?

A

Lubricate movable joints, kept within the synovial capsule

192
Q

What does arthritis damage?

A

Destruction of articular cartilage

193
Q

Bone growth occurs by what?

A

Endochondral ossification - hyaline cartilage is produced and replaced by bone

194
Q

What is intramembranous ossification?

A

Synthesis of bone from an embryonic tissue called mesenchyme

195
Q

What does intramembranous ossification result in?

A

Flat bones

196
Q

What is the epiphyseal plate?

A

A disk of hyaline cartilage that is actively being produced by chondrocytes

197
Q

Where is the epiphyseal plate found?

A

Between the diaphysis and epiphysis

198
Q

What is the epiphyseal line?

A

The fusion point where the diaphysis and epiphysis have fused together

199
Q

What is the bone process called remodeling?

A

Bones are degraded and remade

200
Q

What are osteoblasts?

A

Cells that make bone by laying down collage and hydroxyapatite

201
Q

What do osteoclasts do?

A

Dissolve hydroxyapatite crystals

202
Q

Which hormones control the activity of osteoclasts and osteoblasts?

A

Parathyroid hormone, calcitonin and calcitriol

203
Q

What is calcitriol derived from?

A

Kidney from vitamin D

204
Q

Which hormones controlling the osteoclast to osteoblast activity reduces it?

A

Calcitonin

205
Q

Which hormones controlling the osteoclast to osteoblast activity increases it?

A

PTH and calcitriol

206
Q

What is the effect of parathyroid hormone on the kidney?

A

Increases absorption of calcium

207
Q

What is the effect of parathyroid hormone on the intestines?

A

Increases intestinal calcium absorption

208
Q

What is the effect of calcitriol on the intestines?

A

Increases intestinal calcium absorption

209
Q

What is the effect of calcitriol on the kidneys?

A

Increases reabsorption’s of phosphorus

210
Q

What is the effect of calcitonin on the kidneys?

A

Decreases reabsorption of calcium

211
Q

What is the effect of calcitonin on the intestines?

A

Doesn’t have any

MCAT BIOLOGY FLASHCARDS (23 decks)

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