Anatomy and Physiology

    Cardiovascular System
    In which of the following situations would the greatest pressure be produced?
    Pressure = force ÷ area. The higher the force acting on an area (or the smaller the area that a force acts upon), the greater will be the pressure. The pressure in choice A is greater than in choice D.
    Author: rikazzz Comment
    Reproductive System
    Which of the following is NOT a function of estrogens?
    The corpus luteum is maintained by luteinising hormone.
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    Muscles
    Which list is in the correct order of DECREASING size?
    A myofibril consists of sarcomeres joined end to end; a myofibril contains many myofilaments; a myofibril is larger than a molecule of myosin.
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    Electricity
    The ECG trace on the screen of a cardiac monitor is measured to be 3 cm high. If the sensitivity control was set at 2 cm/mV, what is the value of the voltage being measured?
    3 cm ÷ 2 cm/mV = 1.5 mV.
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    Nervous System
    In the human eye, where does the greatest refraction occur?
    Most refraction occurs as light enters the cornea because the difference between the refractive index of air and that of the cornea is large.
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    Ionising Radiation
    Why are gamma rays able to penetrate “solid” walls but alpha or beta rays cannot? Because:
    It is the absence of an electrical charge that allows photons to pass by electrons and atomic nuclei with being attracted or repelled by them. This means that photons are undeflected unless they suffer a direct hit.
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    Endocrine System
    From where are antidiuretic hormone and oxytocin released?
    ADH and OT are produced in the hypothalamus and transported to the posterior pituitary.
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    Cardiovascular System
    Which of the following statements about the cardiovascular centre of the brain is FALSE?
    Output along fibres of the sympathetic nervous system actually increases heart rate. So choice B is FALSE and answers the question that was asked.
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    Respiratory System
    The greatest amount of air which can be moved in and out of the respiratory system is the:
    Vital capacity includes inspiratory reserve volume, tidal volume and expiratory reserve volume. All can be measured separately by our conscious effort.
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    Chemistry for Physiology
    What holds the primary structure of a protein together?
    Protein primary structure refers to the sequence of the linked amino acids. The link between adjacent amino acids is called a “peptide bond” – a special term reserved for the covalent bond between the C of one amino acid and the N of the adjacent amino acid.
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