Answer:
Xylem cells have no cytoplasm or end walls, meaning they form a tube through which water can pass freely to allow water transport. Lignin strengthens the cell walls, helping to support the plant.
Answer:
C. is unstable, with a short half life
Explanation:
Paracrine hormones are the hormones that act on neighboring cells only. These hormones or chemicals are largely unstable and have a brief life as do not visit the distantly placed target cells. For instance, somatostatin is secreted by D cells of the pancreas. It acts in a paracrine manner and inhibits the discharge of hormones from the neighboring beta and alpha cell.
Likewise, one of the functions of unstable NO gas is to serve as a vasodilator. It is released by epithelium cells and serves to dilate arterioles and relax precapillary sphincters. Then it is degraded.
Answer:
D
Explanation:
plants make their own food not animals, hope this helped :)
The protective covering of the brain
that provides passageways for cerebrospinal fluid (CSF) to drain into the
superior sagittal sinus is called the arachnoid mater.
To add, the arachnoid mater is the middle
of three layers that make up the meninges, or membranes, that surround the spinal
cord and brain.
