When the bundle of processes is pushed in the opposite direction, the cell is hyperpolarized

 

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#Unit 6. System Physiology – Plant

All fruits that ripen in response to ethylene exhibit a characteristic respiratory rise before the ripening phase called a climacteric.

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#Id: 7110

#Unit 6. System Physiology – Plant

In banana, ripening is characterized by a climacteric rise in

respiration rate, as evidenced by the increased CO2 production.

A climacteric rise in ethylene production precedes the increase in CO2 production, suggesting that ethylene is the hormone that triggers the ripening process.

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#Unit 6. System Physiology – Plant

TLS Online TPP Program

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#Unit 6. System Physiology – Plant

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#Unit 6. System Physiology – Plant

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#Id: 7114

#Unit 6. System Physiology – Plant

In the absence of ethylene, ETR1 and the other ethylene receptors activate the kinase activity of CTR1. This leads to a repression of the ethylene response pathway, possibly through a MAP kinase cascade. 

The binding of ethylene to the ETR1 dimer results in its inactivation, which causes CTR1 to become inactive.