Answer:
Viruses cannot reproduce on their own, but inject their DNA into living cells in order to make copies of themselves.
Explanation:
A virus cannot reproduce itself outside the host because it lacks the complicated machinery that a [host] cell possesses.
Answer:
The correct option is d. it causes exchange diffusion
Explanation:
Amphetamines are synthetic substances with a stimulating effect. Their action lies mainly in increasing synaptic levels of monoamines by various mechanisms, including diffusion exchange through membrane transporters. Amphetamine increases extracellular concentrations of serotonin by displacing the neurotransmitter from its specific presynaptic transporter. When amphetamine binds to serotonin transporters, on the one hand it prevents it from entering the terminal and on the other it reverses the recapture mechanism so that serotonin leaves the synaptic space.
Answer:
The correct answer is - option A.
Explanation:
Price floor is a minimum price determined by the government at which a particular item can be sold. It is legal to sell the item on the minimum price which is often imposed by the government when farmers or sellers of the item convince that market price is not fair without a price floor.
In this case the farmers are farmers use improved, drought resistant seeds, which lowers the cost of growing soybeans which can transform the price floor.
Thus, the correct answer is - option A.
Answer: Nuetrons, protons, electrons, elements and compounds
Explanation: Atoms are the smallest components of matter and it is comprised of these three subatomic particles; nuetrons, protons and electrons. Next in the order are the elements (found in periodic table). Elements are made of atoms and compounds are large molecules made of elements. Elements are pure substances that cannot be broken down into smaller substance by chemical reactions whereas compounds can be broken down further.
