Anatomy and Physiology

    Ionising Radiation
    The advantage of computed tomography (CT) over conventional radiography is:
    It is the ability to image internal structures without having them partially obscured by the tissue on either side as is the case for “conventional” radiography that makes CT such a useful diagnostic tool. (Also there is no need to cut the person open to see what is inside!)
    Author: rikazzz Comment
    Renal System
    Alcohol is a diuretic. How does it produce this effect?
    A diuretic causes a greater volume of urine to be produced. ADH promotes the reabsorption of water, so a lack of it will mean less water is reabsorbed from the filtrate, and a greater volume of urine will be produced. The other three choices will cause a decrease in urine volume.
    Author: rikazzz Comment
    Ionising Radiation
    Why are radionuclides that emit low-energy gamma radiation preferred than other radionuclides for in vivo diagnosis using a nuclear medicine technique? Because:
    If most gamma photons emerge from the body, the maximum amount of information will be available, and the minimum amount of radiation dose will be deposited in the patient.
    Author: rikazzz Comment
    Cardiovascular System
    From which structure does blood that enters the right ventricle come?
    Blood passes from the right atrium into the right ventricle, by going through the tricuspid valve.
    Author: rikazzz Comment
    Reproductive System
    What do the thecal cells that surround the follicle produce?
    The thecal cells produce androgens (androstenedione) which diffuse to the granulosa cells which convert androgens to estrogens.
    Author: rikazzz Comment
    Chemistry for Physiology
    Which of the following properties is least likely to be possessed by a covalent, molecular substance?
    A high melting point is characteristic of ionic substances. Some covalent compounds are soluble in water.
    Author: rikazzz Comment
    Cells and Tissues
    If the DNA strand sequence of bases is CTT AGA CTA ATA, what would the tRNA read?
    Guanine (G) must be matched to cytosine (C) and vice versa. Adenine (A) must match with thymine (T). In RNA, uracil (U) replaces thymine; hence U must be matched to A.
    Author: rikazzz Comment
    Respiratory System
    The central chemoreceptors in the brain stem increase breathing rate in response to which stimulus?
    Carbon dioxide that enters the CSF will react with water to form hydronium ions, and these ions stimulate the central chemoreceptors.
    Author: rikazzz Comment
    The Physics of Waves: Light Waves, Sound Waves and Ultrasound
    Which of the following sound levels, if prolonged, will damage the hearing mechanism of the ear without being perceived as painful?
    Prolonged exposure to 90 dB will result in hearing loss and so will 120 dB, but that will be noticeably painful.
    Author: rikazzz Comment
    Cells and Tissues
    Adipocytes are found in which type of tissue?
    Adipocytes are found in fat (adipose tissue) which is a type of connective tissue.
    Author: rikazzz Comment