Anatomy and Physiology

    Measurement, Errors, Data and Unit Conversion
    When 2.25 mg is converted to micrograms, how many micrograms are there?
    There are 1000 μg in each milligram. Hence 2.25 thousands is 2250 (mg to μg: shift the decimal point 3 places to the right).
    Author: rikazzz Comment
    Cardiovascular System
    Finish the sentence correctly. Plasma proteins:
    Plasma proteins are responsible for colloid osmotic pressure. Serum does not include clotting factors – since fibrinogen is a clotting factor and a plasma protein, choice D is incorrect.
    Author: rikazzz Comment
    Chemistry for Physiology
    A hydrocarbon molecule which contains at least one double bond could be an example of which type of compound:
    Alkenes contain at least one double bond between carbon atoms. Alkanes have only single bonds, while alkynes have at least one triple bond between carbon atoms.
    Author: rikazzz Comment
    Nervous System
    What is true about the spinothalamic tract?
    It is ascending – going from spine to thalamus – and ascending tracts carry sensory information to the brain.
    Author: rikazzz Comment
    Nervous System
    Spinal nerves are formed from a dorsal root and a ventral root. What is true of the ventral root?
    The ventral root contains axons of motor neurons. That is, they carry motor information from the brain to the body – this is efferent (outgoing) information.
    Author: rikazzz Comment
    Ionising Radiation
    A particular radionuclide has a half-life of 6 h. When first measured, its activity is 10,000 Bq. Twelve hours later, what will its activity be?
    After one half-life, the starting activity of 10,00 Bq will be halved to 5000 Bq. After another half-life, the activity will be halved again from 5000 to 2500 Bq.
    Author: rikazzz Comment
    Cardiovascular System
    Blood osmolarity is about 290 mosmol/L. What would happen to red blood cells if they were placed in a solution of 180 mosmol/L?
    A solution of 180 mosmol/L is hypotonic, so osmosis would occur, moving water into the RBC. Consequently they would swell and many would lyse (split open). Haemolysis would occur.
    Author: rikazzz Comment
    Ionising Radiation
    The lead aprons that are used for protection of staff in diagnostic radiography procedures do not provide protection against the ionising radiation used in nuclear medicine or radiotherapy. Why is this? Because:
    Diagnostic radiography uses x-rays with an average energy of 70 keV or less, which can be stopped by relatively thin amounts of lead (or lead-like) material. In order to stop the gamma rays used in nuclear medicine imaging, the thickness of the “aprons” would make them prohibitively heavy to wear.
    Author: rikazzz Comment
    Ionising Radiation
    Which statement about the atom and its nucleus is correct?
    The nucleus is tiny compared to the atomic diameter. Choice A is wrong as protons have the positive charge, and neutrons have no charge.
    Author: rikazzz Comment
    Cardiovascular System
    Which blood vessel supplies oxygenated blood to the liver?
    The term hepatic refers to the liver. Arteries supply oxygenated blood (except for the pulmonary artery).
    Author: rikazzz Comment