Answer:
Mechanical barriers — which include the skin , mucous membranes , and fluids such as tears and urine — physically block pathogens from entering the body. Chemical barriers — such as enzymes in sweat , saliva , and semen — kill pathogens on body surfaces.
Answer:
The cell membrane is selectively permeable to ions and organic molecules and controls the movement of substances in and out of cells. The basic function of the cell membrane is to protect the cell from its surroundings. It consists of the phospholipid bilayer with embedded proteins.
<h2>Answer:</h2>
The correct answer is the option C.
Which is we add equal amount of salt in all the water samples.
<h3>Explanation:</h3>
- As in experiment we have to indicate that the boiling point of water increases with the addition of salt.
- Now we also know that water contains many salts as compared to the distilled water.
- So the boiling points of simple water and distilled water would be bit different.
- So we cannot choose one for our experiment. Instead we use all water samples of equal volume adding equal amount of salt in all samples.
- Then we will compare results for a net answer/result of experiment.
Answer:
The three basic types of adaptations, based on how the genetic changes are expressed, are structural, physiological and behavioral adaptations. Most organisms have combinations of all these types
Explanation:
