Clarity transparent when freshly voided becomes turbid cloudy on standing Color

Clarity transparent when freshly voided becomes

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Clarity – transparent when freshly voided; becomes turbid (cloudy) on standing. Color – yellow to amber; varies with urine concentration and diet. Odour – mildly aromatic; becomes ammonia-like on standing. Chemical composition of Urine 5
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Percentage of water – 95%. Three most abundant organic solutes – urea, creatinine, amylase. Four most abundant inorganic solutes – calcium, chloride, potassium, sodium. Specific Gravity Of Urine Ratio of weight of volume of substance to weight of equal volume of distilled water The normal laboratory value – 1.001 – 1.035 Micturition Discharge of urine from the urinary bladder Mechanism Of Micturition 1. Volume of urine that initiates the process – 200-400 ml 2. Receptors involved – Stretch receptors in the wall of the urinary bladder 3. Location and function of the micturition reflex centre – Sacral spinal cord segments s2 and s3. Receives impulses from the stretch receptors and transmits parasympathetic impulses to the urinary bladder wall and internal urethral sphincter 4. Nature of the motor pathway to the detrusor muscle and internal sphincter and their responses – parasympathetic; cause contraction of the detrusor muscle and relaxation of the internal urethral sphincter muscle 5. Nature of the motor pathway to the external sphincter and its response – somatic (inhibitory); somatic motor neurons that innervate skeletal muscle in the external urethral sphincter are inhibited, sphincter relaxes 6. Role of the cerebral cortex – can initiate micturition or delay its occurrence for a limited period 6
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