MD2002 Week 2 Flashcards
(82 cards)
1
Q
what connect the actin filaments in smooth muscle?
A
dense bodies
2
Q
outline smooth muscle contraction
A
- Ca binds to calmodulin
- Ca-calmodulin-MLCK complex leads to phosphorylation of MLC (part of myosin head)
- myosin binds to actin and power stroke occurs
3
Q
outline smooth muscle relaxation
A
- Ca is released from calmodulin
- MLCP removes P from MLC
- myosin head detaches from actin filament
4
Q
what must the free energy change be for a reaction to occur spontaneously?
A
free energy change must be negative for this to occur
5
Q
chemical formula of phosphate
A
PO4^3-
6
Q
what factors affect metabolism? (3)
A
- amount of substrates/products
- amount of key enzymes
- activity of key enzymes
7
Q
steps in the cross-bridge cycle (4)
A
- energized myosin binds to actin when [Ca2+] > 10^-5
- energy is discharged and cross bridge rotates. ADP and P are released
- ATP binds to myosin and breaks link
- ATP is split, producing energized myosin
8
Q
stiffening of skeletal muscles after death
A
rigor mortis
9
Q
source of ATP in muscle that provides 100 twitches
A
creatine phosphate
10
Q
source of ATP in muscle that provides 20000 twitches
A
aerobic glycolysis provides this many twitches in muscle
11
Q
source of ATP in muscle that provides 600 twitches
A
anaerobic glycolysis provides this many twitches in muscle
12
Q
molecular structure of sugar
A
OH at every C + aldehyde group
13
Q
keto acids
A
compound where amine group of amino acid is replaced by carbonyl and can be used for energy
14
Q
NADH
A
nicotinamide adenin dinucleotide
15
Q
niacin (B3) deficiency
A
pellagra: sensitive to sunlight, dermatitis, alopecia (hair loss), glossitis, weakness, ataxia
16
Q
enzyme catalyzing glucose –> glucose-6-P
A
hexokinase
17
Q
phosphofructokinase
A
catalyses fructose-6-P –> fructose-1,6-bisphosphate
18
Q
factors affecting phosphofructokinase activity in glycolysis (5)
A
- high [ATP] allosterically inhibits
- low pH inhibits (lactate accumulation)
- high [citric acid] inhibits
- high [pyruvate] inhibits
- high [fructose-6-P] stimulates
19
Q
energy products of glycolysis
A
2 ATP and 2 NADH produced
20
Q
3 ways to block NMJ transmission
A
- inhibiting Ach synthesis
- inhibiting Ach release
- postsynaptically
21
Q
how depolarising/agonistic NMJ blockers work
A
- persistent depo of motor end plate
- prolonged end plate potential and depo of muscle membrane
- MP above threshold for resetting of V-gated Na channels
- no more muscle action potential generated
22
Q
Phase 2 of depolarizing NMJ blocker
A
prolonged exposure to drug causes “desensitization blockade” (depo cannot occur, even in absence of drug)
23
Q
onset and duration of rocuronium
A
this NMJ blocker has fast onset and medium duration
24
Q
side-effects of pancuronium and rocuronium
A
side effect of these NMJ blockers is tachycardia
25
side effects of atra/mivacurium
side effect of these NMJ blockers is hypotension and bronchospasm
26
side effects of suxamethonium
side effects: bradycardia, cardiac dysrhythmias, raised intraocular pressure, postoperative myalgia, malignant hyperthermia
27
Achesterase drugs that forms carbamylated enzyme complex
neostigmine, pyridostigmine
28
sugammadex
a selective relaxant binding agent (SRBA) against vecuronium and rocuronium
29
structures lying in the anatomical snuff box
radial artery, branches of radial nerve, and cephalic vein lie here
30
what part of talus attaches to navicular?
head of this bone attaches to navicular
31
attachments of lumbricals
arise from tendon of flexor digitorum profundus, insert into extensor expansion
32
definition of screening
a process of identifying apparently healthy people who may be at increased risk of disease/condition
33
sensitivity
how well test picks up having the disease; # of ppl w/ disease detected/# of pp w/ disease
34
positive predictive value
how reliable positive test result is; # of ppl w/ disease and positive test result/# of ppl w/ positive test result
35
possible disadvantages of screening
possible disadvantages: false reassurance, anxiety, harm from test, cost
36
biases in screening programmes
biases:
- participant bias
- lead-time bias
- length-time bias
37
calculate coverage in screening
screened pop/eligible pop
38
calculate uptake in screening
screened pop/invited pop
39
FAD
flavin adenine dinucleotide
40
what vitamin is FAD formed from?
cofactor formed from riboflavin (vit B2)
41
which metabolic pathways occur within matrix of mitochondria?
breakdown of pyruvate and TCA cycle occur here
42
CoA
a nucleotide that contains pantothenic acid (vit B5)
43
where does the ETC occur?
this metabolic pathway occurs across the inner mitochondria membrane
44
protein complexes of the respiratory chain (3)
1. NADH-Q reductase
2. cytochrome reductase
3. cytochrome oxidase
45
plantarflexors from medial to lateral origin
FDL -> TP -> FHL
46
structures behind medial mall (medial to lateral)
Tom Dick And Very Nervous Harry
47
dorsiflexors (medial to lateral)
TA -> EDL -> EHL -> FT
48
what does palmaris longus insert into?
this muscle inserts into palmar aponeurosis
49
where does common synovial sheath terminate?
this structure terminates in the palm, except in the little finger
50
how many interossei are there on each side of hand?
4 dorsal for abduction, 3 palmer for adduction
51
innervations of lumbricals in foot
1 supplied by medial plantar nerve, other 3 by lateral
52
layers of the sole (4)
1. FDB, abductor hallux, abductor digiti minimi
2. quadratus plantae, lumbricals from FDL
3. FHB, FDMB, adductor hallucis
4. interossei
53
what compounds can liver use for gluconeogenesis?
lactate (glycolysis), alanine (transamination), glycerol (lipolysis)
54
endocrine cells of the pancreas (centre to circumference) and their secretions
alpha cells (glucagon), D cells (somatostatin), beta cells (insulin, amylin)
55
roles of insulin (5)
1. glycogen synthesis in liver and muscle
2. glucose uptake in muscle and adipose tissue
3. glycolysis and hence fatty acid synthesis in liver
4. formation of triglycerides in fat tissue
5. protein synthesis in muscle
56
glucagon
hormone secreted when blood [glucose] falls
57
roles of glucagon (3)
1. release glucose from glycogen
2. gluconeogenesis but inhibits its incorporation into glycogen
3. breakdown of triglycerides in fat tissue
58
difference b/w (nor)adrenaline and glucagon
unlike glucagon, their glycogenolytic action is mainly on muscle rather than liver. Lower glucose uptake by muscle so fatty acids are used as fuel instead. Also increase glucagon and inhibit insulin
59
normal blood glucose levels
4-8mmol/L = 80-140mg/100mL
60
hypoglycaemic glucose levels
blood glucose
61
hyperglycaemic glucose levels
blood glucose > 11mmol/L
62
first day of starvation (2)
- muscle shifts from using glucose to fatty acids for fuel
| - liver uses fatty acids, pyruvate,, lactate, and alanine to make glucose for brain
63
later stages of starvation
after 3 days: lots of ketone bodies made
after weeks: brains ability to use these increases and need for glucose and thus amino acids to fuel gluconeogenesis is reduced
64
type 1 diabetes mellitus
autoimmune condition where b-cells of pancreas are destroyed
65
why diabetes causes excessive urination
transporters in proximal tubule of kidney cannot remove all glucose from urine that was taken from blood in glomerulus. Osmosis causes urine to retain water.
66
effects of long-term high blood [glucose]
- polyneuropathy
- retinopathy
- urine infection
- cardiovascular disease (narrowed blood vessels)
- ketoacidosis
67
Bragg equation
sarcomere length = λ/sin0
68
tetanic contraction
sustained muscle contraction evoked when the motor nerve that innervates a skeletal muscle emits action potentials at a very high rate
69
define ketone body
compound made from acetyl-CoA from breakdown of fatty acids
70
3 ketone bodies
1. acetoacetate
2. 3-hydroxybutyrate
3. acetone
71
what are the products of deamination?
NH3 (ammonia) + a keto acid
72
how is protein broken down by the liver?
amino acids pass amino group to pyruvate (transamination) to form alanine. Alanine enters blood and liver converts back to pyruvate to use in making glucose
73
attachments of quadratus plantae
this muscle attaches from plantar surface of calcaneus to tendon of FDL
74
spring ligament
ligament from sustentaculum tali to navicular giving "springy" movement
75
origin of flexor hallucis brevis
this intrinsic foot muscle originates from plantar surfaces of cuboid and lateral cuneiforms
76
origin of adductor hallucis
this intrinsic foot muscle originates from MTs 2-4
77
origin of flexor digiti minimi brevis
this intrinsic foot muscle originates from base of 5th MT
78
where do most intrinsic foot muscles originate from
these muscles originate from calcaneus
79
what is contained in the synovial fibrous flexor sheath (2)
flexor digitorum superficialis and profundus lie under these membranes in the fingers
80
which part of brachial plexus lies underneath clavicle?
divisions of brachial plexus lie underneath this bone
81
challenges with optimizing coverage
- minority ethnic groups
- immigrants
- travellers
- prisoners
- students
- reduced uptake
82
challenges with optimizing uptake
- address change
- communication
- health literacy
- deprivation
- accessibility
- vulnerable group
