Shortcut Methods and Tricks for Solving Numerical Problems on Neural Control and Coordination

1. Reflex Arc:

• For Reflex Arc Calculation:
• Remember that conduction velocity is in m/s, so convert lengths from cm to m if needed.
• Total Reflex time = Sensory Neuron Time + Motor Neuron Time.
• Sensory neuron time or Motor neuron time = (Neuron Length )/ (conduction velocity)

2. Synaptic Transmission:

• For Synaptic Transmission Calculation:
• To find the threshold potential, simply add EPSP (Excitatory Postsynaptic Potential) value to the resting membrane potential.
• For calculating the number of molecules released, multiply the quantal content by the probability of neurotransmitter release.

3. Action Potential:

-Velocity of an action potential and Refractory Period are inversely related. -For Charge Calculation, multiply the amplitude and duration of the action potential.

4. Sense Organs:

• For Focal Length and Dioptric Power:*
• Remember the lens formula: 1/f = 1/u + 1/v, where f is the focal length, u is the object distance (assumed to be infinity for the eye), and v is the image distance (which is the same as the focal length for the eye).
• Dioptric power = 1/ focal length in meters -Remember the formula: wavelength = speed of sound / frequency, where wavelength is the distance between successive crests or troughs of a wave, speed of sound is the speed at which the wave propagates, and frequency is the number of waves passing a point in one second.

5. Hormonal Control:

-Molar Concentration = [ Number of moles of Solute (or Insulin)] / [ Volume of solution] ,where one unit of insulin is equivalent to 0.0347 mg of insulin -For Half-life, use the formula t1/2 = 0.693 * t, where t1/2 is half-life and t is time.

6. Autonomic Nervous System:

-Percentage Increase in Heart Rate = [(Increase in Heart Rate) / (Initial Heart Rate)] * 100 -Total Acetylcholine Molecules Released = (Number of Vesicles) * (Acetylcholine Molecules per Vesicle).

7. Central Nervous System:

-For Brain Weight Percentage, use the formula: Brain Weight Percentage = (Brain Weight / Total Body Weight) * 100. -For Average Diameter Calculation with a circular cross-section, diameter^2 = 4 x Area / π.