Answer:
A
Explanation:
Gram positive bacteria stain violet due to the presence of a thick layer of peptidoglycan in their cell walls, which retains the crystal violet these cells are stained with.
Answer:
Physical changes can easily be reversed but chemical changes cannot because in physical change only state is changed while in chemical change, new substances are formed. For example, when water in liquid form is condensed, it changes into solid form (ice). It is a physical change because water in liquid and solid have the same chemical formula only arrangement of molecules are different. Burning of wood is a chemical change because new substances i. e. carbondioxide and heat is produced.
Skin tears mucus cilia stomach and acid
The right answr is hydrogen bonds
The hydrogen bond or hydrogen bridge is an intermolecular force involving a hydrogen atom and an electronegative atom such as oxygen, nitrogen and fluorine. The intensity of a hydrogen bond is intermediate between that of a covalent bond and that of van der Waals forces.
The helices of the DNA (both strands) are maintained by hydrogen bonds.
The correct answer to the question above would be (a.) shear. The three types of stress that act on Earth's rocks are compression, tension, and shear.The Earth's crust is broken into several parts which are called plates. When these plates are being pulled or pushed together, the Earth's stress now occurs.