Week 2 Flashcards
- glycolysis - force generation, energy usage and fibre types - pharmacology of the neuromuscular junction - radioulnar, knee, elbow and tibiofibular joints - wrist, hand, ankle and foot - citric acid cycle and respiratory chain - metabolic stores - scapular region and glenohumeral joint - palm of hand and sole of foot - metabolic changes in health and disease - sensory receptors - muscle contraction - SIPCEP - Personal protective equipment (PPE) (224 cards)
1
Q
Where does glycolysis take place?
A
The cytoplasm
2
Q
Differentiate between a pyranose and a furanose ring.
A
PYRANOSE: six-membered ring
FURANOSE: five-membered ring
3
Q
How do you call the following process:
keto acid A + amino acid B –> amino acid A + keto acid B
A
Transamination
4
Q
Give the steps of glycolysis according to the type of reaction
A
1- phosphorylation 2- isomerisation 3- phosphorylation 4- cleavage and isomerisation 5- oxidative phosphorylation 6- transfer of phosphate 7- molecular rearrangement 8- dehydration 9- transfer of phosphate
5
Q
What does the first step of glycolysis achieve?
A
Trapping of glucose in the cell by adding a phosphate group to the 6th carbon –> ionized glucose is unable to cross the cell membrane
6
Q
Which two steps of glycolysis consume ATP?
A
STEP 1: phosphorylation of glucose to glucose-6-P
STEP 3: phosphorylation of fructose-6-P to fructose-1,6-biP
7
Q
Which step of glycolysis breaks down a six-carbon molecule into two 3-carbon molecules?
A
STEP 4: fructose-1,6-biP cleaved and isomerized to glyceraldehyde-3-P
8
Q
Which two steps of glycolysis directly produce ATP?
A
STEP 6 and 9: transfer of phosphate from carbon molecule to ADP
9
Q
Give the full name of NAD+. What are its four components?
A
Nicotinamide adenine dinucleotide.
Adenine+ ribose (adenosine) + nicotinamide + ribose
10
Q
Differentiate between NAD and NADP.
A
NAD: C2 of ribose of adenosine sports an OH group
NADP: C2 of ribose of adenosine sports an O-P group
11
Q
Which vitamin provides the nicotinamide necessary for glycolysis?
A
Vitamin B3 - niacin
from diet
12
Q
What is pellagra and what are the symptoms?
A
Pellagra - vitamin B3 deficiency (lack of niacin)
sensitivity to sunlight, dermatitis, alopecia (loss of hair), glossitis, weakness, ataxia, dementia, diarrhea
13
Q
Give the direct net ATP production of glycolysis when the glucose is taken from the blood and when it is taken from glycogen.
A
FROM THE BLOOD: +2 ATP
FROM GLYCOGEN: +3 ATP
14
Q
What happens for glycolysis in anaerobic conditions?
A
NADH builds up without being regenerated by the electron transport chain (oxygen-requiring process).
NADH reoxidised by reducing pyruvate to lactate
15
Q
Which 3 enzymes are main regulators of glycolysis rates?
A
- hexokinase (glucose —> glucose-6-P)
- phosphofructokinase (fructose-6-P —> fructose-1,6-biP)
- pyruvate kinase (phosphoenolpyruvate —> pyruvate
16
Q
What 4 mechanisms influence the rate of phosphofructokinase in glycolysis?
A
INHIBITORS
- high [ATP]
- low pH (associated with lactate accumulation)
- high [citric acid]
STIMULATORS
- high [fructose-6-P]
17
Q
Explain the sliding filament mechanism.
A
Force generation produces shortening of a skeletal muscle fiber. This is caused by the overlapping of thick and thin filaments in each sarcomere, that move past each other, propelled by the movements of the cross-bridges.
18
Q
Give the 4 steps of the cross-bridge cycle
A
1- energized cross-bridge binds to actin
2- conformational change of cross-bridge (cross-bridge moves)
3- ATP binds to myosin, causing the cross-bridge to detach
4- hydrolysis of ATP into ADP + Pi energizes the crossbridge
19
Q
How long does it take for rigor mortis to start?
A
3 to 4 hours
20
Q
Explain the mechanism behind rigor mortis.
A
- cells accumulate calcium so crossbridges bind to actin
- in the absence of ATP, cross-bridges linkage is irreversible
21
Q
What are the 4 functions of ATP in skeletal muscle?
A
- sodium-potassium pump to maintain Na+ and K+ gradients, allowing the membrane to produce and propagate action potentials
- calcium pump to actively transport Ca2+ ions from the cytoplasm back to the sarcoplasmic reticulum, allowing relaxation of the muscle fiber
- myosin ATPase to energize the cross-bridges, allowing provision of energy for force generation
- binding of ATP to myosin to dissociate cross-bridges from actin, allowing the cross-bridges to repeat their cycle of activity
22
Q
What are the 3 mechanisms a muscle fiber can use to produce ATP, and in what kind of physical activities are each of these mechanisms enhanced?
A
CREATINE PHOSPHATE
- phosphorylates ADP
- rapid bursts of higher intensity exercise
OXIDATIVE PHOSPHORYLATION
- phosphorylation of ADP in the mitochondria
- moderate levels of exercise
GLYCOLYSIS
- high levels of exercise
23
Q
On which basis are skeletal muscle fibers classified?
A
- maximal velocities of shortening
- major ATP-producing pathway on which they rely
24
Q
What differs between fast and slow skeletal muscle fibers?
A
They contain forms of myosin that differ in the maximal rate at which they use ATP. This determines the maximal rate of cross-bridge cycling, and thus the maximal shortening velocity.
25
How would you differentiate between oxidative and glycolytic fibers?
OXIDATIVE
- darker
- for long term contraction
- numerous mitochondria
- myoglobin
GLYCOLYTIC
- lighter
- few mitochondria
- numerous glycolytic enzymes in the cytoplasm
- for quick bursts of activity
- large store of glycogen
26
What other name is given to type IIa fibers in skeletal muscle?
fast-oxidative-glycolytic fibers
27
Which type of skeletal muscle fibers present a very rapid decline in tension over time?
Fast-glycolytic (type IIb) fibers
28
Give the two factors and their parameters the total tension that a muscle can develop depends on.
TENSION DEVELOPED BY EACH FIBER
- action potential frequency
- fiber length
- fiber diameter
- fatigue
NUMBER OF ACTIVE FIBERS
- number of fibers per motor unit
- number of active motor units
29
What does control of shortening velocity depend on?
- load on the muscle
- types of motor units in the muscle
- the number of motor units recruited to work against the load
30
Differentiate between disuse and denervation atrophy.
DISUSE ATROPHY
atrophy that comes from inability to use the muscle (arm in a cast, bed rest)
DENERVATION ATROPHY
atrophy that results from nerve damage (loss of function)
31
Give 3 ways to block the neuromuscular junction pre-synaptically.
- local anaesthetics
- general inhalational anaesthetics
- Magnesium ions
- aminoglycosides
- tetracycline
(- botulinum and beta-bungarotoxin toxins)
32
Give 4 clinical uses of post-synaptic neuromuscular blocking drugs.
- endotracheal intubation
- allow surgical access to abdominal cavity
- ensure immobility
- allow relaxation to reduce displaced fracture or dislocation
- decreased concentration of general anaesthetics used
- mechanical ventilation intensive care (infrequent)
- electroconvulsive therapy
33
How many sub-units are there in the nicotinic acetylcholine receptor?
5
34
Give the diameter of the pore of the nicotinic acetylcholine receptor.
0.7nm
35
What is a non-depolarising blocker? Explain their mechanism.
competitive antagonists of nicotinic acetylcholine receptors of the neuromuscular junction
Prevents ACh binding to receptor by occupying the site
- -> decreases the motor end plate potential
- -> decreases depolarisation of the motor end plate region
- -> no activation of the muscle action potential
36
Give 5 examples of non-depolarizing blocking drugs.
- Pancuronium
- Vecuronium
- Rocuronium
- Atracurium
- Mivacurium
37
What is a depolarising blocker? Explain its mechanism. Give one example.
agonist of nicotinic acetylcholine receptors at the neuromuscular junction
Suxamethonium
persistent depolarisation of the motor end plate
- -> prolonged end plate potential
- -> prolonged depolarisation of the muscle membrane
- -> membrane potential above the threshold for the resetting of the voltage-gated sodium channels
- -> sodium channels remain refractory
- -> no more muscle action potentials generated
38
What is the main differentiating feature of depolarising blockers?
initial muscle fasciculations
39
Distinguish between phase 1 and phase 2 of a depolarising block.
PHASE 1
- muscle fasciculations observed, then blocked
- repolarisation inhibited (voltage-gated sodium channels kept inactivated)
- potassium leakage out of the cells (hyperkalaemia)
- very predictable
PHASE 2
- prolonged/increased exposure to drug
- desensitisation blockade: depolarisation cannot occur, even in absence of the drug
40
What side effect is common to atracurium and mivacurium?
histamine release causing hypotension and bronchospasm
41
Which mechanism eliminates mivacurium and suxamethonium?
Plasma cholinesterases
42
How is atracurium eliminated?
Atracurium is unstable at blood pH, and therefore degrades itself (ester hydrolysis and Hofmann elimination)
43
Which non-depolarising blockers are eliminated by the liver?
- pancuronium
| - vecuronium
44
Which depolarising blocker would you find in the urine or the bile?
rocuronium
45
Where would you find either of acetylcholinesterase and plasma cholinesterase?
ACETYLCHOLINESTERASE
conducting tissue, red blood cells, basement membrane of the synaptic cleft
PLASMA CHOLINESTERASE
widespread distribution
46
How do anticholinesterase drugs work?
inhibition of cholinesterase enzymes
- -> less degradation of ACh
- -> increased availability of ACh at the neuromuscular junction
- -> increases duration of activity of ACh at the neuromuscular junction
- -> more ACh to compete with non-depolarising blockers
47
Give the name of 4 anticholinesterase drugs.
- Neostigmine
- Pyridostygmine
- Dyflos
- Parathion
48
Which 2 anticholinesterase drugs act by irreversibly inhibiting acetylcholinesterase?
- Dyflos
| - Parathion
49
What are the effects of anticholinesterases? (13)
CNS
- initial excitation with convulsions
- unconsciousness
- respiratory failure
AUTONOMIC NERVOUS SYSTEM
- Salivation
- Lacrimation
- Urination
- Defecation
- GI upset
- Emesis
- Bradychardia
- Hypotension
- Bronchoconstriction
- Miosis (pupillary constriction)
50
Name two conditions in which anticholinesterases are of clinical use.
- Myasthaenia Gravis
- glaucoma
- Alzheimer's
51
What is Sugammadex?
a SRBA (Selective Relaxant Binding Agent), that reverses the effects of rocuronium and vecuronium
52
How many molecules of CO2 are produced by the citric acid cycle?
2
53
How many molecules of FADH2 and NADH are formed?
FADH2: 1
NADH: 3
54
Where does the C2 molecule that enters the TCA cycle come from?
acetyl-coA
55
Give the full name of FAD.
Flavin Adenine Dinucleotide
56
What nutrient from the diet is necessary to obtain in order to make FAD? What would a deficiency in this nutrient cause?
Vitamin B2 (riboflavin)
lesions of the mucous membrane: cracked sore lips and corners of mouth, similar lesions in the genital region, glossitis, dermatitis, muscle weakness...
57
Where does the TCA cycle take place in the cell?
matrix of mitochondria
58
Which of the outer and inner membrane of a mitochondrion has highly selective permeability?
Inner membrane
59
Which vitamin is found in coenzyme A?
vitamin B5 (pantothenic acid)
60
What type of carriers transport pyruvate through the membrane into the matrix of the mitochondrion?
anti-transporters for the outer membrane
| co-transporter for the inner membrane
61
What is the first step of the Krebs cycle?
condensation of acetyl-coA with oxaloacetate
62
How come keto acids in the TCA cycle can be decarboxylated?
The keto acids formed are quite reactive
63
Where are the proteins associated with the respiratory chain found?
Embedded in the inner membrane of the mitochondrion
64
What are the 4 protein complexes involved in the respiratory chain from start to finish? Which one is the largest?
NADH-Q reductase (largest)
coenzyme Q (ubiquinone)
cytochrome reductase
cytochrome oxidase
65
Name 2 chemicals that target and/or block the respiratory chain.
- Rotenone (insecticide, pesticide)
- Antimycin A (antibiotic, pesticide)
- cyanide
- carbon monoxide (CO)
66
Which of the protein complexes of the respiratory chain has the lowest free energy relative to O2?
Cytochrome oxidase
67
What are the 3 electron shuttles involved in the respiratory chain?
- ubiquinone (Q)
- cytochrome C (cyt C)
- O2
68
Which molecules feed electrons into the respiratory chain?
- FADH2
| - NADH
69
Which ion would you find at very high concentration in the inter-membrane space of the mitochondrion?
H+
70
What is the name of the enzyme that is associated to the respiratory chain but does not take part into electron transfer?
ATP synthetase (H+ ATPase)
71
What are the characteristics of hinge joints?
- articular surfaces are reciprocally shaped
- strong collateral ligaments
- the muscles are grouped at the sides of the joint where they do not interfere with movement
72
What is a composite joint? Give one example.
A composite joint comprises more than 1 joint
Example: the elbow (humero-ulnar, humero-radial and proximal radio-ulnar joint)
73
On which axis are the elbow and knee joints based?
the transverse axis
74
Which bony structure on the ulna does the articular circumference of the radius articulate with?
the radial notch
75
How many joint capsules are there in the elbow?
1
76
What is the distal attachment of the radial collateral ligament?
The annular ligament
77
Where is the elbow joint capsule the weakest?
anteriorly and posteriorly
78
What are the functions of the radio-ulnar interosseal membrane?
- holds the radius and ulna together
- transmit forces from the radius to the ulna
- muscle attachment
79
In which category of people is dislocation of the radial head from the annular ligament quite frequent?
in small children (holding hands of parents)
80
Which 2 joints are involved in pronation and supination of the forearm?
proximal and distal radio-ulnar joints
81
Describe how the fibrous capsule of the knee is not complete/continuous.
ANTERIORLY replaced by
- quadriceps tendon (patellar ligament)
- patella
- fat pads on either side of the patellar ligament
POSTERIORLY
- opening for the tendon of the popliteus
82
The knee joint is said to be augmented by 4 structures. What are these structures?
LATERALLY:
- iliotibial tract
LATERALLY AND MEDIALLY
- patellar retinacula from quadriceps
POSTERIORLY
- oblique popliteal ligament
- arcuate popliteal ligament
83
Name 4 bursae that communicate with the articular cavity of the knee joint.
- suprapatellar bursa
- popliteus bursa
- anserine bursa
- gastrocnemius bursa
84
What is the role of each of the collateral ligaments of the knee?
LATERAL (FIBULAR) COLLATERAL LIGAMENT
prevents adduction of leg
MEDIAL (TIBIAL) COLLATERAL LIGAMENT
prevents abduction of the leg
85
Which of the two collateral ligaments of the knee is fused to both the joint capsule and the medial meniscus?
medial (tibial) collateral ligament
86
What happens when very strong extending forces are exerted onto the lateral (fibular) collateral ligament of the knee?
The fibula breaks, not the ligament
87
What are the 6 functions of the menisci of the knee joint?
- increased congruence of articular surfaces
- dissipate the stress/forces on the articular cartilage
- absorb shock
- decrease friction
- participate in locking of the knee
- proprioception
88
Which part of the menisci of the knee is fully avascular?
the inner 2/3
89
Which ligament may or may not interconnect the two menisci of the knee anteriorly?
transverse ligament of the knee
90
Which of the two menisci of the knee is attached to the joint capsule but not to its associated collateral ligament?
the lateral meniscus
91
To which structures do the meniscofemoral ligaments attach proximally and distally?
PROXIMAL ATTACHMENT
medial condyle of femur
DISTAL ATTACHMENT
posterior horn of lateral meniscus
92
According to what are cruciate ligaments of the knee named?
their tibial attachment
93
What are the roles of the cruciate ligaments?
ANTERIOR CRUCIATE LIGAMENT
- prevents anterior movement of tibia
- prevents hyperextension of knee
POSTERIOR CRUCIATE LIGAMENT
- prevents posterior movement of the tibia
TOGETHER
- pivot for rotary movements
94
What is the carrying angle? Why does its value differ between males and females?
the angle between the long axes of arm and forearm
more pronounced in females (>15 degrees) than in male (10-15 degrees) to account for the wider pelvis
95
Give the 4 flexors of the elbow.
- brachialis,
- biceps brachii,
- brachioradialis,
- pronator teres
96
Which nerve innervates the brachioradialis muscle?
radial nerve
97
Name the 2 extensors of the elbow. Which group of muscles assist them in their function?
- triceps
- anconeus
superficial forearms extensors
98
Which nerve innervates all pronator muscles?
Median nerve
99
What is the insertion of the supinator muscle?
lateral, posterior and anterior surfaces of the proximal third of radius
100
List the contents of the antecubital fossa.
Lateral to medial:
- biceps brachii tendon
- brachial artery and vein
- median nerve
- superficial veins
101
When can medial and lateral rotation of the tibia with respect to femur occur?
with the knee in a semiflexed position and the foot of the ground
102
Name all 7 flexors of the knee.
- biceps femoris
- semitendinosus
- semimembranosus
- gastrocnemius
- gracilis
- sartorius
- plantaris
103
Why is it useful for the patella to increase the insertion angle of quadriceps tendon?
Diminishes the forces exerted on it
104
By which nerve is the main extensor of the knee innervated?
femoral nerve (quadriceps)
105
Which muscles help lock and unlock the knee respectively?
LOCKING
- vastus medialis
- gluteus maximus and tensor fascia lata through the iliotibial tract
UNLOCKING
- popliteus
106
What are the boundaries of the popliteal fossa?
- biceps femoris
- semimembranosus
- tendon of semitendinosus
- lateral and medial heads of the gastrocnemius
107
What are the contents of the popliteal fossa?
- popliteal artery (medial) and vein
- tibial nerve
- common fibular nerve
- posterior cutaneous nerve of thigh
- terminal part of saphenous vein
- lymph nodes
- fat
108
Which tendon would you tap to evaluate deep tendon reflexes in the elbow and knee? Which nerve and spinal segments would it specifically test?
BICEPS REFLEX
- biceps tendon in antecubital fossa
- musculocutaneous nerve (C5 and C6)
KNEE REFLEX
- patellar ligament (= patellar tendon, quadriceps tendon)
- femoral nerve (L3 and L4)
109
Which nerve innervates latissimus dorsi?
thoracodorsal nerve
110
What are the borders of the quadrangular, lower and upper triangular space respectively?
QUADRANGULAR SPACE
- humerus
- teres major
- teres minor
- long head of triceps
UPPER TRIANGULAR SPACE
- teres minor
- teres major
- long head of triceps
LOWER TRIANGULAR SPACE
- teres major
- humerus
- long head of triceps
111
Under which form and where are carbohydrates stored in the body?
glycogen mainly in liver and muscle
112
What proportion of glycogen is hydrolysed and then phosphorylated using ATP to make glucose-6-P?
10% (at branching: 1-6-linkage)
113
Weight for weight, how much more energy can triglycerides produce compared to glycogen?
6 times more
114
What is a triglyceride? What other name can it be given?
ester of glycerol and 3 fatty acid chains
triacylglycerol
115
What are diacylglycerols mainly used for?
Cell signalling
116
Is ATP generated directly from lipolysis?
No
117
In which tissue does lipolysis take place? Where are the products metabolised?
LIPOLYSIS - adipose tissue
| PRODUCT METABOLISM - liver
118
Which process forces the formation of ketone bodies when only lipids are available as fuel?
GLUCONEOGENESIS
oxaloacetate --> pyruvate --> glucose
so no oxaloacetate to drive the TCA cycle so acetyl-coA from fatty acids converted to ketone bodies
119
Which 3 amino acids can be deaminated?
- glutamate
- threonine
- serine
120
Give 2 examples of molecules that can be used for gluconeogenesis.
- glycerol
- carbon backbone of amino acids
- pyruvate
121
What is the largest source of protein that can be broken down in time of need?
Muscles
122
What fuels can the brain normally use?
only glucose
123
What keeps the brain from using fatty acids as fuel?
the blood brain barrier
124
Which two tissues cannot export glucose?
- brain
| - muscle
125
What happens to lactate once it passes into the blood?
lactate converted back into glucose by liver
126
Which amino acid can be converted by the liver into pyruvate in order to make glucose?
alanine
127
Give two factors that affect triglyceride storage in adipose tissue.
- glucose availability
| - hormones
128
What frequency of stimulation produces single twitch? summation? tetanic contraction?
SINGLE TWITCH
muscle relaxes completely between stimuli
SUMMATION
stimuli closer together do not allow muscle to relax fully
TETANIC CONTRACTION
stimuli so close together the muscle reaches a steady maximum tension, without being able to relax
129
Give the Bragg equation of diffraction.
sarcomere length = wavelength / sin (angle between the zero and first order diffraction spots)
130
What is the optimal resting length for a sarcomere of skeletal muscle? How would it compare to that of cardiac muscle? Why?
skeletal muscle: 2.1 - 2.2 micrometers
cardiac muscle is below --> prevents tetanic contractions
131
What are the 3 tension parameters of a skeletal muscle?
- passive/resting tension
- peak tension
- active tension (= peak tension - passive tension)
132
Does contraction of a sarcomere bring the Z and M lines closer together?
Yes
133
Give the main features of each of the fed and fasted states of metabolism.
FED (ABSORPTIVE) STATE
- shortly after meal when new nutrients are available
- anabolic metabolism
- provision of energy stores or for growth and maintenance
- some molecules used immediately
FASTED (POSTABSORPTIVE) STATE
- body drawing upon fuel stores
- catabolic metabolism
- depletion of fuel stores
134
Which cells of the pancreas produce insulin? glucagon? somatostatin?
INSULIN - beta cells
GLUCAGON - alpha cells
SOMATOSTATIN - D cells
135
Which 5 processes does insulin stimulate?
- glycogen synthesis in muscle and liver
- glucose uptake into muscle and adipose tissue
- glycolysis and fatty acid synthesis in liver
- formation of triglycerides in fat tissue
- protein synthesis in muscle
136
What stimulates the pancreatic cells to secrete insulin?
- elevated blood glucose
| - parasympathetic nervous system
137
What stimulates glucagon release?
low blood glucose concentration
138
Glucagon stimulates gluconeogenesis. What action must it also have for it to stay available in the blood?
inhibits glucose incorporation into glycogen
139
By what are adrenaline and noradrenaline respectively secreted?
ADRENALINE: adrenal medulla
NORADRENALINE: neurons of the sympathetic nervous system
140
Which organ does glucagon target compared to adrenaline and noradrenaline?
GLUCAGON: liver
| ADRENALINE/NORADRENALINE: muscle
141
Ho do adrenaline and noradrenaline influence insulin and glucagon?
- increase glucagon secretion
| - inhibit insulin secretion
142
What is the normal blood glucose concentration range?
4-8 mmol/L (80-160mg/100mL)
143
What are the respective boundaries for hypo and hyperglycemia?
HYPERGLYCEMIA: > 10 or 11 mmol/L
HYPOGLYCEMIA: < 3 mmol/L
144
For how long can the body withstand starvation on its fuel stores?
1 to 3 months, depending on the level of physical activity
145
Which 2 blood molecular concentrations will go up in the first days of starvation?
- ketone bodies
| - fatty acids
146
Which mechanisms allows glucose to be spared for the brain in starvation?
- gluconeogenesis using proteins (preserved as long as possible)
- muscles use fatty acids instead of glucose
- liver uses pyruvate, lactate, alanine and fats from adipose tissue to make glucose for the brain
147
Which metabolic adaptation from the brain can be observed in later stages of starvation?
brain becomes more tolerant of lowered blood glucose + gradually gains the ability to use ketone bodies as fuel
148
Why is the body adapting to use less glucose in later stages of starvation important for survival?
reduced need for amino acids for gluconeogenesis --> reduced rate of muscle breakdown
149
What are the symptoms of untreated diabetes mellitus?
- profuse urination
- thirst
- hunger
- sugar in urine
150
How are diabetes type I managed/treated?
- insulin injections as required
| - restriction of carbohydrate intake
151
What percentage of cases does diabetes mellitus type II account for?
90%
152
In type II diabetes, what other condition is metabolism comparable to?
prolonged fasting
153
Why is untreated diabetes associated with excessive urination?
amount of glucose into the kidney tubule too high for the transporters to remove it all
- -> higher osmotic strength of urine
- -> harder for kidney to reabsorb water
- -> urine volume is greatly increased
154
In severe cases of diabetes mellitus, which chemical other than glucose would be found in the urine as well?
acidic ketone bodies
155
Which organs are likely to be damaged in diabetes mellitus?
- blood vessels and other cardiovascular structures
- eyes
- kidneys
156
What is the name of the recess within the distal radio-ulnar joint that facilitates movement?
Sacciform recess
157
What is the only movement allowed by the distal tibio-fibular joint?
slight movement during dorsiflexion
158
What is the malleolar mortise?
the posterior wall for the talus formed by the inferior transverse tibio-fibular ligament
159
What type of bones are metacarpals?
long bones
160
How many phalanges are there in total in the body?
14 x 4 = 56
161
Name the tarsal bones of the foot.
PROXIMAL ROW: talus, calcaneus
navicular
DISTAL ROW: medial cuneiform, intermediate cuneiform, lateral cuneiform, cuboid
162
Which of the carpal bones does not articulate with the radius?
pisiform
163
Which of the tibia and fibula articulates with the talus?
Both
164
Which 3 features do the capsules of the wrist and ankle joint have in common?
- loose fibrous capsule
- synovial folds within the capsule
- strong ligaments to reinforce the joint
165
What is a condyloid joint? Give one example.
joint with 1 transverse and 1 sagittal axis
example: radiocarpal joint, metacarpophalangeal joints, metatarsophalangeal joints
166
What is the common flexor origin of the wrist?
medial epicondyle of the humerus
167
Name the 3 flexors of the wrist.
- flexor carpi radialis
- flexor carpi ulnaris
- palmaris longus
168
Name the 4 flexors of the ankle. What nerve supplies them?
- gastrocnemius
- soleus
- tibialis posterior
- plantaris
tibial nerve
169
Name the 3 extensors of the wrist. What nerve supplies them?
- extensor carpi radialis longus
- extensor carpi radialis brevis
- extensor carpi ulnaris
radial nerve
170
What is extension of the ankle? Which muscle is responsible for this movement? Which nerve supplies this muscle?
extension of ankle = dorsiflexion
tibialis anterior
deep peroneal nerve
171
What are the abductors and adductors of the wrist?
ABDUCTORS (on lateral -radial- side)
- extensor carpi radialis longus
- extensor carpi radialis brevis
- flexor carpi radialis
- abductor pollicis longus
ADDUCTORS (on medial -ulnar- side)
- extensor carpi ulnaris
- flexor carpi ulnaris
172
Distinguish between the intercarpal joints and the midcarpal joint. Name one proximomedial intercarpal joint.
INTERCARPAL JOINTS
between carpal bones within a row (proximal or distal)
example: pisotriquetral joint (between pisiform and triquetral bones)
MIDCARPAL JOINTS
between carpal bones of different rows (proximal to distal)
173
How do intercarpal and midcarpal joints make it easier for infection to spread?
Intercarpal and midcarpal joints share a common articular cavity with the carpometacarpal joints.
174
At which joint does the extension and abduction of the wrist happen?
the midcarpal joint
175
On which ligament is stability of the subtalar joint highly dependent?
the interosseal ligament of the subtalar joint
176
Give the names of the 2 ligaments of the transverse tarsal joint that support both the joint and the plantar arches?
- spring ligament
| - long plantar ligament
177
What is the site for surgical amputation of the foot?
transverse tarsal joint
178
What is the interest of carpometacarpal joint 1 having a loose joint capsule?
increased movement for the thumb
179
Name the 3 extrinsic flexors of the fingers.
- flexor digitorum superficialis
- flexor digitorum profundus
- flexor pollicis longus
180
Which two flexors in the forearm are not supplied by the median nerve?
- flexor digitorum profundus
| - flexor carpi ulnaris
181
Name the 5 extrinsic extensors of the fingers. By which nerve are they supplied?
- extensor pollicis longus
- extensor pollicis brevis
- extensor indicis
- extensor digitorum
- extensor digiti minimi
radial nerve
182
Name the 3 extrinsic extensors of the toes. By which nerve are they supplied?
- extensor hallucis longus
- extensor digitorum longus
- fibularis tertius
deep fibular (peroneal) nerve
183
Name the 2 extrinsic flexors of the toes. By which nerve are they supplied?
- flexor digitorum longus
- flexor hallucis longus
tibial nerve
184
Define mechanoreceptor and give three examples that are common to both skin tactile sensibilities and deep tissue sensibilities.
sensory receptor which detects mechanical compression or stretching of the receptor or of tissues adjacent to the receptor
- free nerve endings
- expanded tip endings
- spray endings
- encapsulated endings
185
Give 3 types of mechanoreceptors specific to deep tissue sensibilities.
- muscle endings
- muscle spindles
- Golgi tendon receptors
186
What type of sensory stimulus do free nerve endings transmit?
mechanically-induced pain
187
Where would you find Pacini's corpuscles? What does it detect? What are his 4 main features?
deep layers of dermis of both glabrous and hairy skin
high frequency vibrations (40-500Hz)
- largest mechanoreceptor (2mm long)
- onion like encapsulation of nerve endings
- rapidly adapting
- low activation threshold (high sensitivity)
188
Where would you find Meissner's corpuscles? What do they detect?
between dermal papillae of glabrous skin
touch, flutter, low frequency vibration (2-40Hz)
189
Which mechanoreceptor works with Meissner's corpuscles to determine texture? What does it detect on its own?
Merkel disks
static touch, light pressure
190
Which mechanoreceptor responds to skin stretch? Where is it especially abundant?
Ruffini corpuscles
hands, fingers, soles of feet
191
What do skin hair cell receptors respond to? Where are they found?
- muscular movement of the hair
- external displacement of the hair
wrapped around the follicle of each hair
192
Name the 3 types of sensory receptors other than mechanoreceptors and chemoreceptors.
- thermoreceptors
- nociceptors
- electromagnetic receptors
193
Which 6 sensory stimulus do chemoreceptors respond to and where are each sensed?
- taste --> tastebuds
- smell --> olfactory epithelium
- arterial oxygen --> receptor of aortic and carotid bodies
- osmolality --> neurons in or near supraoptic nuclei
- blood CO2 --> surface of medulla and in aortic and carotid bodies
- blood glucose, amino acids, fatty acids --> hypothalamus
194
What is a receptor potential?
change in the electrical potential of a receptor's membrane once it has been stimulated (by mechanical deformation, receptor-binding, change in membrane temperature or electromagnetic radiations)
195
What is the maximum amplitude of most sensory receptors potentials?
100mV (extremely high intensity of sensory stimulus)
196
Complete the sentence:
the more the receptor potential rises above the threshold level for eliciting action potentials in the nerve fiber...
... the greater the action potential frequency
197
Complete this sentence regarding the relationship between stimulus intensity and sensory receptor potential:
the stronger the stimulus applied to a sensory receptor,...
... the higher the amplitude of the receptor potential
198
For a non-damaging stimulus, what is its intensity coded by in the sensory nerve?
the frequency of action potentials
199
Explain the labelled line principle.
Nerves terminate at a specific point in the CNS and the type of sensation felt is determined by the point in the nervous system to which the fiber leads
200
When does phantom limb sensation arises?
when sensory neurons from absent limbs are spontaneously active
201
Differentiate between slowly and rapidly adapting sensory receptors.
RAPIDLY ADAPTING
receptor potential decrease rapidly in the presence of constant stimuli --> goes back under threshold quite rapidly
SLOWLY ADAPTING
receptor potential stays above the threshold level for a while in the presence of constant stimuli
202
What are the 3 factors at play in the localisation of stimulus?
- size of the individual nerve fibre receptive field
- density of sensory units
- the amount of overlap in nearby receptive fields
203
What are variations in the result of the two point discrimination test due to? Give and example of two areas with very different results.
result of the receptive field size and the receptor density in the area
lips and back
204
What is lateral inhibition?
Information from afferent neurons whose receptors are at the edge of a stimulus are strongly inhibited compared to information from the stimulus centre
205
True or false:
Sensory receptors at determining absolute levels than at detecting changes in space or with time.
FALSE
206
To what part of the body does the second order neuron of a somatosensory pathway project from and to?
FROM either spinal cord or brain stem
| TO thalamus
207
Which specificity of somatosensory pathway means that loss of sensation in discrete areas can be used to determine where neuronal lesions may lie?
the sensory tract are specific in their paths in the nervous system
208
What is the palmar aponeurosis?
a triangular condensation of deep fascia that thickens as 4, interconnected longitudinal bands that continue with the fibrous flexor sheaths
209
Name each of the 4 thenar and hypothenar muscles.
THENAR
- abductor pollicis brevis
- opponens pollicis
- flexor pollicis brevis
- adductor pollicis
HYPOTHENAR
- abductor digiti minimi
- flexor digiti minimi
- opponens digiti minimi
- palmaris brevis
210
How many lumbricals, palmar interossei and dorsal interossei are there respectively in each hand? What are their function?
LUMBRICALS: 4
- flex metacarpophalangeal joints
- extend interphalangeal joints
PALMAR INTEROSSEI: 3
- adduct fingers
DORSAL INTEROSSEI: 4
- abduct fingers
211
Which spinal root supplies the small muscles of the hand? Through which nerves?
T1, through the ulnar and median nerves
212
Between which structures does the extensor retinaculum of the hand extend? What does it do?
- radius
- styloid process of ulna
- triquetrum
- pisiform
holds extensor tendons in place in their synovial sheaths
213
Which two ligaments are attached to the flexor retinaculum of the hand?
- superficial palmar ligament (between styloid processes of radius and ulna)
- deep transverse carpal ligament (between pisiform, hook of hamate, scaphoid and trapezium
214
What is the carpal tunnel made of? Which structures pass through it?
- proximal carpal bones
- flexor retinaculum
- median nerve
- tendons of superficial and deep flexors of fingers
215
What are the contents of the anatomical snuff box?
- radial artery
- branches of the radial nerve
- cephalic vein
216
Name the 3 types of grip.
- power grip
- hook grip
- precision handling grip
217
Tendons of which of flexor digitorum superficialis or flexor digitorum profundus split in the hand?
flexor digitorum superficialis
218
What are the roles of plantar aponeurosis?
- grip
| - weight bearing
219
How many retinacula are there around the ankle? Name them.
3
- extensor retinaculum
- flexor retinaculum
- fibular retinaculum
220
What are the boundaries of the tarsal tunnel?
- talus
- calcaneus
- inferior surface of sustentaculum tali
- flexor retinaculum
221
Which structures pass through the tarsal tunnel?
- tendons of flexor digitorum longus, flexor hallucis longus, tibialis posterior
- posterior tibial artery
- posterior tibial vein
- tibial nerve
222
What are the 3 plantar arches? What are their functions
- medial longitudinal
- lateral longitudinal
- transverse
- weight bearing/distribution
- shock absorption
- resilience
- spring in the stride
223
What 3 features support the arch?
- shape of bones
- ligaments
- msucles
224
Name the muscles responsible for inversion and eversion?
INVERSION
- tibialis anterior
- tibialis posterior
EVERSION
- fibularis longus
- fibularis brevis
