Answer:
Hypertonic
Explanation:
Hypertonic solutions have less water ( and more solute such as salt or sugar ) than a cell. Seawater is hypertonic. If you place an animal or a plant cell in a hypertonic solution, the cell shrinks, because it loses water ( water moves from a higher concentration inside the cell to a lower concentration outside ).
Answer;
-On the polar end or the hydrophillic end of the protein.
Explanation;
-Each amino acid has at least one amine and one acid functional group as the name implies. The different properties result from variations in the structures of different R groups.The R group is often referred to as the amino acid side chain.
-Side chains which have various functional groups such as acids, amides, alcohols, and Amines will impart a more polar character to the amino acid. Polar amino acids include serine, threonine, asparagine, glutamine, histidine and tyrosine.
Therefore; serine being a polar or hydrophillic amino acid will be found on the polar side chain of the protein.
Answer:
Cholesterol is a structural component of the cell membranes of animals. Because of cholesterol that provides cell membrane structural integrity and fluidity, animal cells need not to have cell walls such as that in bacterial and plant cells.Cholesterol reduces permeability of lipid membranes. ... Cholesterol plays has a role in membrane fluidity but it's most important function is in reducing the permeability of the cell membrane. Cholesterol helps to restrict the passage of molecules by increasing the packing of phospholipids.
Explanation:
Answer:
"As a molecule moves through the plasma membrane it passes through <em>a hydrophilic layer of phospholipid heads then a hydrophobic layer of phospholipid tails and then another hydrophilic layer of phospholipid heads".</em>
Explanation:
Biological membranes are formed by two lipidic layers, proteins, and glucans.
Lipids characterize for being amphipathic molecules, which means that they have both a hydrophilic portion and a hydrophobic portion at the same time. These molecules have a lipidic head that corresponds to a negatively charged phosphate group, which is the polar and hydrophilic portion. They also have two lipidic tails that correspond to the hydrocarbon chains -the apolar and hydrophobic portion- of the fatty acids that esterify glycerol.
Membrane lipids are arranged with their hydrophilic polar heads facing the exterior and the interior of the cells, while their hydrophobic tails are against each other, constituting the internal part of the membrane.
Through this lipidic bilayer, some molecules can move from one side of the cell to the other, which happens because of concentration differences. When this occurs, molecules must pass through the hydrophilic layer of phospholipid heads then through the hydrophobic layer of phospholipid tails and then again through another hydrophilic layer of phospholipid heads.
