CBSE Class 10th Science Chapter 7 Control & Coordination (#Neuroscience)

 

Living beings show movements to get some advantage based on changes around their environment. All movements in response to changes in environment are controlled by Brain. Nervous System: Information around us are sensed nerve cells.

 Information collected at dendrite tip of nerve cells cause chemical reaction which create electric impulse. This impulse travels from the dendrite to the cell body, and then along the axon to its end. At the end of the axon, the electrical impulse sets off the release of some chemicals. These chemicals cross the gap, or synapse, and start a similar electrical impulse in a dendrite of the next neuron. This is a general scheme of how nervous impulses travel in the body. A similar synapse finally allows delivery of such impulses from neurons to other cells, such as muscles cells or gland.

Nervous system: Brain gets input from sensors ( receptors) & gives command to muscles.  If for some emergency condition like heat, signal goes directly to motor like muscle movement to save body from heat, this information is then given to brain.

 average human brain contains about 86 billion nerve cells, called neurons. These are the building blocks of our brain. Neurons communicate with each other by sending chemical and electrical signals.

Each neuron is connected with other neurons across tiny junctions called “synapses”. Impulses rush along tiny fibres, like electrical wires, from one neuron to the next.

Exocytosis is the process by which cells release particles from within the cell into the extracellular space.

Ligand gated Cation channel

Hormones: are  chemicals in endocrine system released to control growth & development & to control blood pressure, insulin level, mood etc.

Endocrine glands are ductless, they secret chemical directly into blood. petuitary gland in brain releases Growth Hormones, deficiency of which results in dwarfness.