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.
The fact that they can breed but cannot produce fertile offspring shows that they are different species. T<span>hey may have different characteristics which means they cannot breed </span>successfully, too.
I hope this helps! :-)
xo Leafling
Hi sorry but i don't have an idea but i know that a dna profile is based on fingerprints I'm not exactly sure have a nice day
<span>C. Transitional Fossil refer to the fossils which trains is the intermediary between it's ancestral group and derived descendant group,as a sign of evolutionary process</span>
Well I believe it’s answer A. copper because copper is used to make wiring in a smartphone
