Answer:
C. The substance does not directly harm tissues and is not a pathogen, but nevertheless triggers an inflammatory response.
Explanation:
When a person is allergic to a substance, his or her immune system recognizes a harmless substance, such as components in food, pollen, or dust, as a treat. As a consequence, it starts an immune response that leads to inflammation. The substance that starts the allergic reaction is called an allergen, and it is not a pathogen because it is not a real threat to the body since it does not infect cells. When the allergen enters the body, it binds to antibodies that are in contact with a special type of cell. These specific cells will release a substance known as histamine. Histamine will produce an inflammatory reaction affecting different tissues in our body. For example, it can make us sneeze, have a running nose, swelling parts of our body, have itchiness and redness, amongst others.
Answer:
D. There is no enough oxygen in the culture fluid
Explanation:
The cells in the test tube need to carryout one of the important metabolic processes of living organisms - respiration. The process involves the breakdown of glucose to generate energy for other metabolic processes in the cell.
Respiration can be carried out in the presence of oxygen (aerobic) or in the absence of oxygen (anaerobic). Human cells are primarily aerobic but can carryout respiration anaerobically in the presence of inadequate oxygen.
For aerobic respiration, glucose is broken down in the presence of oxygen to produce carbon-dioxide, water and energy in the form of ATP:

<em>In the absence of oxygen, the glucose becomes converted to lactic acid and a smaller amount of ATP is produced as compared to aerobic respiration.</em>
<em>Hence, lactic acid gradually builds up in the absence of oxygen due to anaerobic respiration.</em>
The correct option is D.
Answer:
Option (B).
Explanation:
Neurons or nerve cell are the basic structural and functional unit of the nervous system. Fibers are the thread like long projection of the nerve cells.
Neurons are classified into three fibers- Group A fibers, B fibers and C fibers. The group C fibers cannot capable of doing the saltatory conduction of the nerve impulse because they are unmyelinated.
Thus, the correct answer is option (B).
This statement is inaccurate because food handlers need to prepare food at the quickest rate possible. This is to prevent spoilage from happening because the changes in temperature in which the food is exposed has something to do with the development of certain kinds of bacteria that can be harmful to a person's health.
Answer:
Liver regeneration is the process by which the liver is able to replace lost liver tissue from growth from the remaining tissue. The liver is the only visceral organ that possesses the capacity to regenerate. The liver can regenerate after either surgical removal or after chemical injury.Explanation: