Shortcut Methods
** Numerical’s on Neural Control and Coordination for JEE and CBSE Board Exams:**
1. Action Potential:
- Resting membrane potential: -70 mV to -80 mV.
- Threshold potential: -55 mV to -65 mV.
- Action potential peak: +40 mV to +50 mV.
- Absolute refractory period: 1-2 milliseconds.
- Relative refractory period: 5-10 milliseconds.
2. Synapse Transmission:
- Acetylcholine (ACh) release per vesicle: 10000-100000 molecules.
- Neurotransmitter concentration in synaptic cleft: 0.1-1 mM.
- Diffusion distance across synaptic cleft: 20-30 nm.
- EPSP amplitude: 0.5-1 mV.
- IPSP amplitude: 1-2 mV.
3. Ion Channels:
- Sodium channel conductance (peak): 10-100 pS.
- Potassium channel conductance (peak): 150-300 pS.
- Leak channel conductance: 1-10 pS.
4. Receptors:
- Acetylcholine receptor density (in neuromuscular junction): 10000-15000 per square micrometer.
- Binding constant of acetylcholine to nicotinic ACh receptor: 10-7-10-9 M.
- Number of ACh molecules required for receptor activation: 2.
5. Neurotransmitters:
- ACh synthesis rate: 1-10 picomoles per gram of tissue per minute.
- Half-life of ACh in the synaptic cleft: 0.5-1 millisecond.
- NE synthesis rate: 0.1-1 picomole per gram of tissue per minute.
- Half-life of NE in the synaptic cleft: 1-2 milliseconds.
6. Central Nervous System:
- Number of neurons in the human brain: 100-1000 billion.
- Number of synapses in the human brain: 1000-10000 trillion.
- Nerve conduction velocity in myelinated fibers: 1-120 meters per second.
- Nerve conduction velocity in unmyelinated fibers: 0.5-2 meters per second.
7. Reflexes:
- Stretch reflex latency (knee-jerk reflex): 20-40 milliseconds.
- Withdrawal reflex latency: 50-100 milliseconds.
8. Autonomic Nervous System:
- Resting heart rate: 60-80 beats per minute.
- Maximum heart rate during exercise: 180-220 beats per minute.
- Blood pressure (systolic/diastolic): 120/80 mmHg (resting) to 160/100 mmHg (during exercise).
- Respiratory rate: 12-16 breaths per minute (resting) to 40-50 breaths per minute (during exercise).