Anatomy and Physiology

    Chemistry for Physiology
    In what form is most of the lipid component of our food in?
    Our dietary lipids are in the form of triglycerols (a glycerol molecule and three fatty acids).
    Author: rikazzz Comment
    Respiratory System
    What is the “cribriform plate”?
    The cribriform plate of the ethmoid bone has many foramina through which pass olfactory nerves that transmit sensory information from inhaled air to the olfactory bulbs.
    Author: rikazzz Comment
    Cardiovascular System
    According to Boyle’s law, what will happen in a fixed amount of gas if its volume decreases?
    Pressure is inversely proportional to the volume, so if volume decreases, the pressure will increase. Boyle’s law applies to gas at a constant temperature.
    Author: rikazzz Comment
    Cardiovascular System
    In the haemostasis process, what forms as a result of the extrinsic and intrinsic pathways?
    The extrinsic and intrinsic pathways form “prothrombinase” (also called prothrombin activator) from factor X.
    Author: rikazzz Comment
    The Physics of Waves: Light Waves, Sound Waves and Ultrasound
    If the frequency of a sound is 1000 Hz, what will its period be?
    Period = 1/frequency, hence = 1/1000 = 0.001 s
    Author: rikazzz Comment
    Biomechanics
    The magnitude of the traction force in a Hamilton-Russell traction is determined by;
    The moveable pulley allows the one cord to exert more than one force on the leg. So the magnitude of the force is determined by adding the forces vectorially.
    Author: rikazzz Comment
    Renal System
    Given that the specific gravity of a urine sample is 1.009, which of the following statements is correct?
    SG is a measure of urine density (or concentration). It is the ratio of urine density to water density, so it has no units.
    Author: rikazzz Comment
    Cardiovascular System
    The resting systolic blood pressure of a person has been measured in the brachial artery (when it is at the level of the heart) to be 115 mmHg. What is the likely systolic pressure of this person when standing at rest, measured in the posterior tibial artery at the level of the ankle?
    When standing, there is a column of blood filling the posterior tibial artery (PTA) that rises up to the aorta. The column is about 130 cm tall for a man of about 1.75 m in height. This “head” of liquid exerts a hydrostatic pressure on the wall of the PTA that is in addition to the systolic pressure produced by the pumping action of the left ventricle. A column of 130 cm of blood exerts a pressure of about 100 mmHg (1 mmHg = 1.36 cm H2O) which is in addition to the 115 mmHg original systolic value.
    Author: rikazzz Comment
    Renal System
    Which hormone causes an increase in permeability to water in the collecting ducts of the kidney?
    ADH. If the collecting ducts are permeable to water, more water will be reclaimed from the filtrate. This will decrease its volume, and there will be less diuresis and hence anti-diuretic hormone.
    Author: rikazzz Comment
    Renal System
    Which of the following statements about the structures in the loop of Henle is correct?
    The thin descending limb is impermeable to urea.
    Author: rikazzz Comment