A 52-year-old woman presents to her primary care physician for her annual checkup. She lost her job 6 months ago and since then she has been feeling worthless because nobody wants to hire her. She also says that she is finding it difficult to concentrate, which is exacerbated by the fact that she has lost interest in activities that she used to love such as doing puzzles and working in the garden. She says that she is sleeping over 10 hours every day because she says it is difficult to find the energy to get up in the morning. She denies having any thoughts about suicide. Which of the following neurotransmitter profiles would most likely be seen in this patient?
AIncreased dopamine
BDecreased serotonin and norepinephrine
CIncreased norepinephrine
DDecreased acetylcholine
EDecreased gamma-aminobutyric acid
During exercise, what is the primary mechanism for increased oxygen delivery to active muscles?
ADecreased blood viscosity
BIncreased cardiac output
CIncreased hemoglobin affinity
DEnhanced oxygen diffusion
An investigator is examining tissue samples from various muscle tissue throughout the body. She notices that biopsies collected from a specific site have a high concentration of sarcoplasmic reticulum, mitochondria, and myoglobin; they also stain poorly for ATPase. Additionally, the cell surface membranes of the myocytes in the specimen lack voltage-gated calcium channels. These myocytes are found in the greatest concentration at which of the following sites?
AVentricular myocardium
BTunica media
CLateral rectus muscle
DGlandular myoepithelium
ESemispinalis muscle
+ 7 more in the PDF
Browse all chapters