Explanation:
1. cell membranes are partialy permeable, only allowing passage to some certain molecules.
2. diffusion is the movement of molecules across partially permeable membrane down concentration gradient.
3. the molecules are too big to pass through partially permeable membrane. the concentration of the molecule might be higher in the cell than in the solution/surroundings.
Answer:
The way I would separate the shell fragments from the sand would be by using a filter. As shell fragments are larger than sand. So I would use a filter with 2 mm spaces to separate them. Now, for the sand separation from the water, I would heat the water so it would evaporate and connect a tube to another recipient making the sand stay in the first tube and the water vapor cools in the tube to precipitate in the other recipient. Three mixtures I have prepared at home are chocolate milk, coffee and cream, and lemon juice and tea.
Explanation:
To understand this answer we have to remember a few things. First, mixtures always have solute and solvent. The solvent is the most liquid component of the mixture and it can incorporate the more solid element in its composition to carry it. Now, there are several methods to separate them, barrier methods like filters are the first and more basic ones, as they are aimed to separated big solutes. While evaporation can be used to separate two very liquid elements. Like distillation of alcohol to separate the most concentrated oil from the alcohol.
Sounds like ADD (<span>Attention-Deficit Disorder).</span>
The soles of people’s feet have a greater concentration of sensory receptors because more people are ticklish on the bottoms of their feet than the backs of their necks. There are more neurons in your appendages especially the ends of them because they are the furthest from the brain. Getting a tattoo on your feet vs. the back of your neck hurts more as well, making the soles of your feet have the greater concentration.
Answer:
12
Explanation:
Suppose the four different strains are P, Q, R, S. Thus, the first infection can be from any of the four strains and it occurs in 4 ways.
Since an individual cannot be infected again with the strain from which he/she is been previously infected;
Then, at the second time;
The possible number of strain to be infected with = 4-1 = 3 ways
Thus; the number of possible different levels of severity can be viewed by forming two lettered word P, Q, R, and S without repetition which is:
= 4 × 3
= 12
