Maharashtra State Board · Class 10 · Biology · Chapter 3

Control and Coordination — Formula Sheet

Board Formulas

5 formulas

1.Reflex Arc Sequence★
$Stimulus \to Receptor \to Sensory neuron \to Spinal cord \to Motor neuron \to Effector \to Response$
Fast, automatic response. Bypasses the brain.
2.Nerve Impulse Speed
$v \approx 100 m/s (myelinated)$
Myelinated axons transmit faster due to saltatory conduction. Unmyelinated: ~1 m/s.
3.Neurotransmitter Release at Synapse
$Impulse \to C a^{2 +} influx \to Vesicles fuse \to Neurotransmitter release$
Chemical signal at gap between two neurons.
4.Auxin Effect on Plants★
$Auxin \to Cell elongation \to Phototropism$
Higher auxin on shaded side ⇒ shoot bends towards light.
5.Feedback Regulation of Hormones
$Level high \to Gland stops secretion; Level low \to Gland secretes$
Homeostasis. Example: TSH regulates thyroid, thyroid regulates TSH.