Respuesta B.
Explanation:
(((First part of the small intestine))). It connects to the stomach. The duodenum helps to continue digesting food that comes from the stomach. It absorbs nutrients (vitamins, minerals, carbohydrates, fats, proteins) and water from food so that the body can use them.
It is one of the beginning compounds.
This is the answer for many reasons. First off, it is not one of the ending compounds. It is only the end compound for photosynthesis. Second, it does not react to water as that is yet again photosynthesis. It does not react with carbon dioxide as carbon dioxide is what initially creates oxygen within cellular respiration.
Hope this helps!
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.
