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>.
(D)an atom can join with other kinds of atoms.
Basically he explained what a molecule is.
Answer:
A national park is a reserved area of land owned by the government which is protected from industrialization, human exploitation, and pollution.
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Difference Between Wildlife Sanctuary, Biosphere Reserves and National Park.
Wildlife SanctuaryBiosphere ReservesNational ParksNot requiredSubject to the particular area of the biosphere reservePermission is required
<span>Excess carbohydrates in Animals are stored as fats. It mainly gets stored in the skeletal muscles and liver in the form of glycogen. Carbohydrates actually get stored in the form of long polymers of glucose molecules or as glycogen starch. They provide energy to the animals for performing their daily duties. Carbohydrates are generally considered the fuel for all organisms, and without this most animals would become sloth and would be unable to perform the regular jobs. Carbohydrates are actually very easy to metabolise and hence generate quick energy. </span>
The answer is carbohydrate
