There are a few different types of cell-cell interactions. Some of these interactions are meant for big molecules that enter and exit the cell called, endocytosis (entering the cell) and exocytosis (exiting the cell). For smaller particles like amino acids, water, ions and other solutes there are different types of direct contact between the cells called gap junctions.
False because you don't need computer models to make climate (I'm just guessing I'm not sure if I'm right but I tried)
Answer:
The correct answer is it occurs naturally by diffusion.
Explanation:
Diffusion is one of the most important passive transport mechanism which helps in the movement of small molecules and gases across the plasma membrane down their concentration gradient.
In simple words diffusion deals with the transport of small molecules and gases from the region of high concentration to the low concentration region untill the contration of both the regions become equal.
Question: When an atom that has no charge loses two electrons, it becomes a:
A: positive ion.
B: negative ion.
C: positive isotope.
D: negative isotope.
Answer:
When an atom that has no change loses two electrons, it becomes "positive ion".
Explanation:
It is known that electrons hold a negative charge. So, when the negative charge that is electrons are taken out an atom then the number of electrons become less in number as compared to the number of protons. Hence, the atom attains a positive charge.An isotope is formed when an atom shows same number of protons and different number of neutrons. So, when an atom loses 2 electrons there will be no change in the number of neutrons. Therefore, an isotope will not form.Thus, it is concluded that when an atom with no charge loses two electrons, it becomes a positive ion.
Answer and Explanation:
To test the presence of glucose, we can perform <u>Benedict's test.</u> This test detects the presence of reducing sugars (e.g. glucose) by adding <u>Benedict's reagent.</u> This reagent contains sodium carbonate, sodium citrate and copper(II) sulfate pentahydrate. When the mixture is heated, reduce cupric compounds (Cu2+) are formed which results in the change in color from clear blue to brick-red, yellow or green.
To test the presence of glucose in the food sample, we will dissolve a small volume of food sample in water and put it in the test tubes, in triplicates. Then we will add 3 mL of Benedict's reagent. Also, we will run positive and negative controls. For positive controls, we will add glucose directly and for negative, we will not add any glucose or other reducing sugars (also in triplicates each). Then we will heat the test tubes in water water for 5-10 minutes. In the positive control, the color would change to green, yellow or brick red; but in negative control, it will stay blue (see figure attached for explanation). For the food sample, if the glucose or reducing sugars would be present, the color will change. In case of low sugar, it will be green, but increasing sugar content would change the color to yellow/orange and red. Because the experiment will be conducted in triplicates, we would be also able to verify if the results were consistent and there was no human or technical error.
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