Cells must move materials through the {membrane} and throughout the {cytoplasm} to maintain {homeostasis} Movement of substances is regulated because membranes are {semi} permeable. Membranes are {phospholipid} bilayers that contain embedded {proteins} The cells external environment and cytoplasm are aqueous, meaning that solutes such as {salt}are dissolved in a solvent called {water} Water may travel slowly through the membrane by {osmosis} or quickly through protein channels called {aquaporins}
One of the common arguments why the process of transplanting non-human organs which came from animals may be considered as an ethical act is that antigens on the surface of the non-human organs are not significantly rejected in the process. Although its research is still substantial, it is still considered as a matter of ethical issue.
Sure. What’s the questions? Post them
Answer:
a. movement can occur both upward and downward in the plant
Explanation:
The phloem loading causes the accumulation of sugars in the sieved elements generating a negative solute potential (quedas), with a drop in water potential (ψw), so water enters the sieved elements increasing the turgor pressure (ψp). With the discharge of phloem in the drain occurs lower concentration of sugars in the screened elements, increases the solute potential, becoming positive, thus the phloem water potential increases and thus the water leaves the conducting vessel. In the specific case of sugar movement in the phloem, it can be stated that this movement can occur both up and down in the plant.
According to the Food and Nutrition Board, of the National Academy of Sciences, 10% to 35% of kilocalories should come from protein.
There are six classes of food, but the three majors ones, that are require in large quantity are carbohydrates, proteins and fats and oils. The Food and Nutrition board gave recommendation about the quantity of these classes of food that should be taken on a daily basis. It is recommended that, 45% to 65% of kilocalories should come from carbohydrates while 20% to 35% come from fat.