- Based on the review article by Gamu et al., which of the following is/are FALSE regarding
sarcolipin knockout (SLNKO) mice?
a) the Ca2+/ATP coupling ratio of SERCA pumps was higher in SLNKO mice than in wildtype
mice
b) SLNKO mice expend more energy during submaximal treadmill exercise than wildtype
mice
c) the contribution of SERCA activity to resting energy expenditure was lower in SLNKO mice
than wildtype mice
d) SLNKO mice were unable to maintain body temperature following acute cold exposure
e) SLNKO mice display impaired non-shivering thermogenesis
b) SLNKO mice expend more energy during submaximal treadmill exercise than wildtype
mice
- Based on the review, during isometric contractions of skeletal muscle, what percentage does
SERCA approximately contribute towards ATP consumption?
a) 65%
b) 20%
c) 30%
d) 5%
e) none of the above
c) 30%
- Based on the review article, what is one of the major differences between sarcolipin (SLN)
and phospholamban (PLN)?
a) they do not have any differences
b) SLN inhibits SERCA whereas, PLN activates SERCA
c) SLN is found endogenously within oxidative skeletal muscle, whereas PLN is found within
smooth muscle
d) SLN remains bound to SERCA at high Ca2+ concentrations, whereas PLN dissociates
e) SLN inhibits Ca2+ uptake, whereas PLN accelerates Ca2+ uptake
d) SLN remains bound to SERCA at high Ca2+ concentrations, whereas PLN dissociates
Based on the review article by Gamu et al. (2020), what is TRUE about the effect of thyroid
hormones (i.e. T3/T4) on metabolism?
a) hyperthyroidism (high thyroid hormone levels) decreases metabolism by increasing
expression of PLN, which increases slippage and ATP consumption
b) thyroid hormones reduce ATP turnover by improving SERCA coupling efficiency
c) thyroid hormones increase metabolism by increasing heat released during SERCA
pumping
d) thyroid hormones increase metabolism which is independent from SERCA
e) none of the above
c) thyroid hormones increase metabolism by increasing heat released during SERCA
pumping
- As discussed during lectures, which of these statements regarding the high-fat feeding
experiment with SLNKO mice is TRUE?
a) mice lacking sarcolipin are less susceptible to diet-induced obesity and glucose
intolerance
b) adaptive thermogenesis in response to high-fat feeding is enhanced in SLNKO mice
c) high-fat feeding does not lead to glucose intolerance in wildtype mice
d) serum catecholamine levels are increased in high fat-fed SLNKO mice only
e) none of the above
d) serum catecholamine levels are increased in high fat-fed SLNKO mice only
- Based on the Nature paper on DGF15, where would you expect the receptor protein GFRAL
to be exclusively expressed?
a) liver
b) adipose Tissue
c) skeletal Muscle
d) hindbrain
e) kidney
hindbrain
. Based on the research paper by Wang et al., GDF15 treated mice exhibit ____________ food
intake and _____________ energy expenditure and muscle fatty acid oxidation.
a) decreased; decreased
b) decreased; increased
c) increased; decreased
d) increased; increased
e) decreased, no change in
decressed increased
- Mice treated with GDF15 experienced weight loss at which temperature?
a) 21°C
b) 37°C
c) 29°C
d) a) and c)
e) b) and c)
21and 29
- In GDF15-treated mice, INCREASES in energy expenditure were mediated by:
a) increased activity of B-adrenergic receptors in skeletal muscle
b) decreased activity of B-adrenergic receptors in skeletal muscle
c) increased activity of nicotinic-cholinergic receptors in smooth muscle
d) none of the above
e) all of the above
a) increased activity of B-adrenergic receptors in skeletal muscle
- The SERCA coupling ratio is REDUCED by the protein regulator __________, but NOT by
___________:
a) sarcolipin (SLN), myoregulin (MLN)
b) phosholamban (PLN), dwarf open reading frame (DWORF)
c) myoregulin (MLN), dwarf open reading frame (DWORF)
d) phosholamban (PLN), myoregulin (MLN)
e) sarcolipin (SLN), phosholamban (PLN
e) sacro lipin and not PLN
. According to a nexus for muscular adaptive thermogenesis article, which of the following is
TRUE in response to sarcolipin knockout mice (Sln−/−) and its effects on SERCA pumps?
a) the apparent coupling ratio of SERCA within oxidative muscle was more efficient in Sln−/−
mice relative to wild-type controls because of their lower rates of ATP per Ca2+ transported
b) Sln−/− mice expend less energy during submaximal treadmill exercise however are able to
maintain body temperature following acute cold exposure
c) the contribution of SERCA activity to resting energy expenditure of isolated muscle was
lower in Sln−/− mice
d) mice over-expressing SLN develop diet-induced obesity resulting from efficient SERCA
metabolism, whereas Sln−/− mice are resistant to diet-induced obesity
e) a) and c) are both true
e ) a and c
a) the apparent coupling ratio of SERCA within oxidative muscle was more efficient in Sln−/−
mice relative to wild-type controls because of their lower rates of ATP per Ca2+ transported
c) the contribution of SERCA activity to resting energy expenditure of isolated muscle was
lower in Sln−/− mice
- Based on the Gamu et al. review, which class of ATPase does SERCA fall under?
a) A Type
b) F Type
c) V Type
d) P Type
e) E Type
p type
- Which SERCA regulator(s) enhances Ca2+ uptake by physically displacing sarcolipin
(SLN), phospholamban (PLN), and myoregulin (MLN)?
a) thyroid adenoma associated (THADA)
b) small ankryin 1 (sAnk1)
c) dwarf open reading frame (DWORF)
d) a) and b) only
e) b) and c) only
c dworf
- Based on the lectures, which of the following contributes the MOST to field metabolic rate
in the majority of adult humans?
a) the thermic effect of food (TEF)
b) physical activity
c) basal metabolic rate (BMR)
d) protein Synthesis
e) adaptive Thermogenesis
c) basal metabolic rate (BMR)
- According the Nature article by Wang et al., what role does the hormone GDF15 play in
weight loss during calorie restriction?
a) GDF15 decreases energy expenditure by slowing metabolism
b) GDF15 reduces food intake and increases energy expenditure by activating a signaling
axis in skeletal muscle
c) GDF15 promotes weight loss by inhibiting calcium absorption in muscle cells
d) GDF15 works by directly increasing the size of fat cells to burn more calories
e) GDF15 reduces muscle activity, leading to decreased ATP use and energy expenditure
b) GDF15 reduces food intake and increases energy expenditure by activating a signaling
axis in skeletal muscle
- What primary mechanism allows GDF15 to sustain weight loss during caloric restriction?
a) suppressing liver metabolism
b) enhancing energy expenditure via skeletal muscle calcium futile cycling
c) increasing thyroid hormone activity
d) inducing fat oxidation in brown adipose tissue
e) stimulating physical activity levels
b) enhancing energy expenditure via skeletal muscle calcium futile cycling
- Based on the article by Wang et al., what does GDF15 reduce independently of reductions in
food intake?
a) obesity
b) insulin resistance
c) non-alcoholic steatohepatitis (NASH)
d) all of the above
e) none of the above
d) all of the above
- From the readings about energy burn in muscle being boosted by a hormonal signalling axis,
which of the following statements is FALSE?
a) activating both GLP1 receptor and GFRAL leads to more weight loss than either of those
treatments alone
b) beyond the first two weeks of the study, the GDF15-treated mice continued to lose weight
while the calorically restricted mice plateaued
c) the increased energy expenditure that’s associated with GDF15-induced weight loss, is
mediated by changes in thermogenesis in fat tissue
d) in the calcium futile cycle, the efficiency of calcium uptake into the sarcoplasmic reticulum
compartment of muscle cells is reduced
e) all of the above are true
c) the increased energy expenditure that’s associated with GDF15-induced weight loss, is
- Which of the following best describes the thermic effect of feeding (TEF)?
a) the heat produced by skeletal muscle during exercise
b) the energy required for digestion, absorption, and metabolism of food
c) the heat generated by brown adipose tissue in response to cold exposure
d) the energy expended to maintain body temperature at rest
e) the energy lost through sweating during physical activity
b) the energy required for digestion, absorption, and metabolism of food
