Answer:
The plant cell wall is strengthened by the molecular structure of cellulose. Cellulose is made up of ß-glucose arranged upside down, this arrangement aided hydrogen bonds between the hydrogen ions of the hydroxyl group and oxygen of the of the ring of same betta -glucose.
The aggregation of the hydrogen bonds give bundles of strong tensile strength of cellulose called the microfibrils (of 60-70 celluose molecules).They are held together in bundled called fibers.T<u>hese is the source of plant cell walls strength.
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Collagen is the main extracellur matrix (EM) in animal cells.It is a glycoprotein made up of 25%of body protein of animals.Each collagen molecule is made of helix shaped ,three polypeptide chains, wound around each other to form<u> triple helix.</u>The bonds holding helix together are hydrogen and covalent bonds.
Each triple helix is attached to adjacent collagen molecule, parallel to it. The covalent bonds formed a cross link which held the collagen molecules together forming FIBRILS. This gives flexibility to collagen, while maitaing strong tensile strength. This is what is responsible for the structural strength of cell membrane
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.The EM,is futher reinforced with carbohydrate molecules(proteoglycans) which<u> aided in water movements by osmosis following sodium movements into the matrix.</u>
The same meaning would be shy
Answer:
cast
Cast fossils are the type people are most familiar with, as they make up the spectacular dinosaur skeletons that on view in museums. Cast fossils occur when minerals deposit into the mold left by the rotting organic material, resulting in a three-dimensional replica of the hard structures of the plant or animal
your welcome
Answer:
ok I don't know the first one
2.nucleus is the power of cell and that make a new organisms and also it control all of cell activities.
3.green
4.ya b/c it is made or get in green pigment.
5.that is unspecified of plant cell and get in chloroplaste.
The correct answer is: Release of neurotrasmitters from the synaptic vesicles
Action potential travels through the membrane of the presynaptic cell causing the channels permeable to calcium ions to open. Ca2+ flow through the presynaptic membrane and increase the Ca concentration in the cell which will activate proteins attached to vesicles that contain a neurotransmitter (e.g. acetylcholine), Vesicles fuse with the membrane of the presynaptic cell, thereby release their contents into the synaptic cleft-space between the membranes of the pre- and postsynaptic cells.
