Chapter 20, Problem 10Q

(a)

Summary Introduction

To predict: The given molecules that can pass through gap junctions.

Concept Introduction: Cells are interconnected and communicated through a protein channel called gap junction (in animals) and Plasmodesmata (in plants). Small molecules pass generously across the cell membrane to reach neighboring cells through these junctions. The protein channels mediate the transfer of chemical signals in the form of ions and molecules to neighboring cells. Exchange of these types of proteins is very helpful which acts as a chemical messenger to start or stop (regulate) cellular processes.

Gap junctions also function as the gateway for regulating the influx and efflux of molecules and change their structure according to block the flow of ion molecules whenever required. Gap junctions play an important role in regulating the permeability of the cell wall. Plasmodesmata are a structure that is found in the plants. They are the tiny channels or pores present in between two cells that connects them to transfer intracellular molecules with each other. They are the living bridges between cells and allow cellular communication within them by directly penetrating the primary and secondary cell wall.

(b)

Summary Introduction

To predict: The given molecules that can pass through Plasmodesmata

Concept Introduction: Cells are interconnected and communicated through a protein channel called gap junction (in animals) and Plasmodesmata (in plants). Small molecules pass generously across the cell membrane to reach neighboring cells through these junctions. The protein channels mediate the transfer of chemical signals in the form of ions and molecules to neighboring cells. Exchange of these types of proteins is very helpful which acts as a chemical messenger to start or stop (regulate) cellular processes.

Gap junctions also function as the gateway for regulating the influx and efflux of molecules and change their structure according to block the flow of ion molecules whenever required. Gap junctions play an important role in regulating the permeability of the cell wall. Plasmodesmata are a structure that is found in the plants. They are the tiny channels or pores present in between two cells that connects them to transfer intracellular molecules with each other. They are the living bridges between cells and allow cellular communication within them by directly penetrating the primary and secondary cell wall.