Anatomy and Physiology

    Chemistry for Physiology
    A human excretes approximately 450 mmol of urea in urine each day. Given the molar mass of urea is 60 g, what is the mass of urea excreted daily?
    As the molar mass of urea is 60 g, this means that 1 mol of urea has a mass of 60 g. Now 450 mmol is LESS than 1 mol, so the number must be less than 60 g. By numbers: 450 mmol × 60 g/mol = 0.45 × 60 = 27 g
    Author: rikazzz Comment
    Body Temperature, Energy and Heat Loss
    Why does the evaporation of perspiration from our bodies cool our skin? Because the evaporated water carries with it the:
    Radiation and convection are not involved. Latent heat of fusion refers to the heat required to melt a solid, and latent heat of vaporisation refers to the heat that leaves the body with the evaporated sweat.
    Author: rikazzz Comment
    Cells and Tissues
    Which of the four types of tissue do all organs contain?
    All organs have capillaries and a blood supply. Blood is a connective tissue, and capillaries are made of epithelial tissue; the arterial end of capillaries has a precapillary sphincter which is made of smooth muscle cells. All organs are innervated so they contain nervous tissue.
    Author: rikazzz Comment
    Gastrointestinal System
    Which hormone is responsible for contraction of the gall bladder?
    One of the functions of CCK is to cause the gall bladder to contract.
    Author: rikazzz Comment
    Endocrine System
    Which structure controls the endocrine system and integrates the activities of the nervous and endocrine systems?
    Hypothalamus secretes regulatory hormones that control endocrine cells in the ant pit gland, produces ADH and oxytocin and contains “autonomic centres” that exert neural control over endocrine cells of the adrenal medullae.
    Author: rikazzz Comment
    Chemistry for Physiology
    A hydrocarbon is a type of compound that contains:
    Hydrocarbon means hydrogen combined with carbon.
    Author: rikazzz Comment
    Nervous System
    Which of the following statements about the blood-brain barrier (BBB) is correct?
    Hormones and ions cannot pass through the BBB. (It is astrocytes, not Schwann cells, which form part of the BBB; the brain floats on CSF; CSF is formed by the choroid plexus).
    Author: rikazzz Comment
    Muscles
    Which muscle is one of the “hamstrings” group?
    The hamstrings are in the thigh. “Femoris” refers to the femur bone. Biceps femoris is one of the three hamstring muscles. Choices A and C are on the arm (from “brachii”).
    Author: rikazzz Comment
    Ionising Radiation
    The term “radioactive” when applied to the nucleus of an atom refers to which one of the following phenomena?
    Choice B is wrong as x-rays don’t come from a nucleus. Choice C is wrong as sometimes a nucleus is in an “excited” state and returns to ground state by emitting a gamma ray while the nuclear structure is unchanged. Choice D is wrong as a nucleus which has the optimum ratio of neutrons to protons is not unstable.
    Author: rikazzz Comment
    The Physics of Waves: Light Waves, Sound Waves and Ultrasound
    Ultraviolet radiation is damaging to the eye because:
    UV radiation is absorbed by the eye lens, and the energy of the absorbed photons can break the bonds between atoms.
    Author: rikazzz Comment