植物细胞壁中的特定区域纤维素定向和无otropic 机械性质

 Every plant cell has a cell wall that protects the cell, provides structural support, and gives the cell shape. Cellulose, the main structural component of the plant cell wall, makes up over 30% of plant matter. It is the most abundant organic compound on earth.  Cellulose is an unbranched polysaccharide composed of linear chains of glucose molecules linked by β (1→4) glycosidic bonds.
As a cell matures, its cell wall specializes according to its type. For example, the...

Plants have rigid cell walls that are made up of cell wall polysaccharides that mediate cell-cell adhesion. The primary cell walls of plants consist of two independent and interacting polysaccharide networks: a pectin matrix that embeds the second network comprising cellulose and hemicelluloses.
Pectins are complex heteropolymers mainly composed of negatively-charged α-D-glucopyranosyl uronic acid and some neutral glycosyl residues such as α-L-rhamnopyranose, α-L-arabinofuranose,...

Microtubules are small hollow tubes in eukaryotic cells. The cell wall microtubules are polymerized dimers of two globular proteins, α-tubulin and β-tubulin, two globular proteins. With a diameter of about 25 nm, microtubules are the widest components of the cytoskeleton. They help the cell resist compression and provide a track along which vesicles move through the cell or pull replicated chromosomes to opposite ends of a dividing cell. Microtubules go through quick cycles of...

The plant cell wall gives plant cells shape, support, and protection. As a cell matures, its cell wall specializes according to the cell type. For example, the parenchyma cells of leaves possess only a thin, primary cell wall.

Plants are multicellular eukaryotes with tissue systems made of various cell types that carry out specific functions. Different tissues work together to perform a unique function and form an organ. Organs working together form organ systems. Vascular plants have two distinct organ systems: a shoot system and a root system. The shoot system consists of two portions: the vegetative (non-reproductive) parts of the plant, such as the leaves and the stems, and the reproductive parts of the plant,...

Animal and plant cells not only differ in their structure, function, and mode of nutrition but also in how they reproduce, specialize, and organize into complex structures.
Cell Division
Though both plant and animal cells divide by mitosis (for non-gametic cells) and meiosis (for gametic cells), they differ in the specifics of this process. Unlike animal cells, plant cells lack centrosomes — an organelle responsible for organizing the spindle fibers and segregating the chromosomes during...