Question

10) Explain the possible changes to urine volume,

pH, specific gravity

and sodium excretion after drinking different solutions : water,sodium chloride, sodium bicarbonate????

2) Explain the relationship between stimulus strength and amplitude of muscle response in general?

6)What is the effect of raising each hand on the blood pressure in the left arm? Explain your results. What are the physiological causes for the changes you see in the blood pressure and/or heart rate post exercise?

Answer 1

(1) Changes in urinary volume:

• Water: An increased amount of water generally increases the amount of urine that is excreted out and makes urine less concentrated.
• Sodium chloride: Salts tend to decrease urine output by absorbing more water from tubules and makes urine more concentrated.
• Sodium bicarbonate: It increases the urine volume.

Changes in urine pH:

• Water: The urine pH becomes slightly alkaline.
• Sodium Chloride: The pH would be basic due to an increased amount of salts in urine.
• Sodium bicarbonate: It makes the pH alkaline

Changes in specific gravity:

• Water: Drinking more water would decrease the specific gravity of urine.
• Sodium Chloride:Specific gravity of Sodium Chloride is more than water. Thus, specific gravity of urine would increase.
• Sodium bicarbonate: Urine's specific gravity would increase.

(2) There is a positive relationship between muscle response and stimulation. An increased stimulation would show an increase muscle response provided that the strength of stimulus is between threshold and maximal stimulus.

(3) When the right hand is raised, the blood pressure in your left hand would remain the same and that of the right hand would decrease. Similarly, when the left hand is raised, the pressure in your left hand would decrease and that of the right hand would remain the same.

Post-exercise, the systolic pressure would increase drastically as the the heart starts pumping blood more rigorously, as a result of which the cardiac output increases.