The rubbery matrix of cartilage is secreted by , whereas produce the fibers and ground substance that form the matrix of fibrous connective tissue.

The correct answer is - Chondroblasts; Fibroblasts

Explanation:

Mesenchymal progenitor cells will form chondrocytes combinedly called Chondroblasts that is responsible for the secretion of the rubbery matrix of cartilage.

Fibroblast on other hand produces fibers and ground substance. These ground substances and fibers make the matrix of the fibrous connective tissue.

the solute can move "downhill," from regions of higher to lower concentration, relying on the specificity of the protein carrier to pass through the membrane. this process is called passive transport or facilitated diffusion, and does not require energy.