...very thin, porous walls form networks called...
...across the thin walls of the capillaries...
...across the capillary walls. The gill capillaries...
...have relatively thin walls and function as...
...ventricles have thicker walls and contract much...
...spreading to the walls of the ventricle,...
...throughout the ventricular walls. The ventricles are...
...The very thin walls of capillaries consist...
...elastic fibers. Artery walls are three times...
...thick as the walls of veins. The...
...veins. The thicker walls of arteries provide...
...recoil) of artery walls helps maintain blood...
...and thin capillary walls promote the exchange...
...exerts against vessel walls, is much higher...
...thick and elastic walls of arteries play...
...pressure. The elastic walls of the arteries...
...muscles in arteriole walls to contract, a...
...muscles in the walls of arterioles constricts...
...muscles in the walls of veins and...
...across the thin walls of capillaries. At...
...the thin endothelial walls of the capillaries....
...of the vessel walls helps draw fluid...
...Cartilage reinforcing the walls of the larynx...

...Modifications of cell walls also play a...
...cells have primary walls that are relatively...
...most lack secondary walls. The protoplast of...
...have thicker primary walls than parenchyma cells,...
...cells, although the walls are unevenly thick....
...have thick secondary walls usually strengthened by...
...rigid secondary cells walls before the protoplast...
...still elongating, secondary walls are deposited in...
...thick, lignified secondary walls. Sclereids impart hardness...
...The thickened cell walls remain as a...
...vessels have secondary walls interrupted by pits,...
...where only primary walls are present. Water...
...Because their secondary walls are hardened with...
...vacuole. The end walls, the sieve plates,...
...have thick, lignified walls that give wood...
...diameters and thinner walls than the cells...
...in the cell walls of cork cells...