Answer:
<u>d. Transport proteins within the membrane serve as a tunnel for molecules to enter the cell.
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Explanation:
Solutes are typically moved across the cell through either passive or active transport. The cells, surrounded by a bilipid layer or plasma membrane is amphiphlic- its polar, hydrophilic lipid heads face outwards, while their non-polar hydrophobic lipid tails face inwards towards each other.
While lipid-soluble molecules move across the layer easily, it is also difficult for charged and also large molecules to move across its surface, into the cell. Transmembrane channels, <u>embedded within the membrane</u>, help to maintain selective permeability as transport proteins, pores and gated channels. Simple diffusion happens as a method of passive transport in cells through plasma membranes.
The solutes travel through the plasma membrane in the process of diffusion from regions of high concentration to regions of low concentration; this occurs without the use of energy. <u>Molecules moving against their concentration require active transport mechanism to cross the membrane</u>.
Answer:
Root hairs appear in the root maturation zone and differentiate from unspecialised cells called trichoblasts.
Explanation:
Root hair arises as a small protrusion surrounded by a cell wall, they are found in the piliferous area; they can originate in unspecialised epidermal cells, in some called trichoblasts. The bump begins to elongate and moves away from the epidermis, forming root hair. The root hairs as they lengthen, it is seen that their content shows a polarized distribution, the apical part is constituted mainly by vesicles secreted by the Golgi apparatus that contain the precursors of the cell wall that are to be released by exocytosis. Trichoblasts can be arranged in different ways, there are roots where any of the cells that are part of the rhizodermis can give rise to a root hair. In other roots, trichoblasts and atricoblasts have been seen to be distinguished alternately along a row of cells.
Answer:
Centrioles is only found in animal cells
Answer:
A. Extra thick fur
Explanation:
Because the winter is cold and little body fat and a dark colored fur will get it killed faster, but long ears can help the bunny hear the danger but I don't think there will be any predetors out in the harsh snow.
The sentences that make sense are "Volatile liquids are flammable" and "Liquids burn easily."
