EVERYDAY SCIENCE

Detailed explanation-1: -To allow for cell wall expansion during growth, primary walls are thinner… Secondary cell walls are responsible for most of the plant’s mechanical support as well as the mechanical properties prized in wood.

Detailed explanation-2: -The gram positive cell walls are much thicker than the gram negative ones. The gram positive cell wall is usually between 20 and 80 nm thick while the gram negative cell wall is usually between 5 and 10 nm thick. The cell wall forms a boundary around the cell, to support and protect the cell.

Detailed explanation-3: -Being thick and rigid, secondary cell walls not only allow tracheids and vessels to resist the negative pressure generated by transpiration but also provide mechanical strength crucial for structural support and protection to the plant body.

Detailed explanation-4: -Thickened walls are formed usually as secondary cell walls (SCWs), deposited at the inner side of primary cell walls (PCWs). SCWs are organized in laminar and patterned structure, mainly composed of cellulose, hemicellulose and lignin (Zhong et al. 2019).