Answer:
Longitudinal
Explanation:
Longitudinal waves have the same direction of vibration as their direction of travel. This means that the movement of the medium is in the same direction as the motion of the wave. Some longitudinal waves are also called compressional waves or compression waves.
Answer:
Stem cells
Explanation:
These cells will speacialise into specific functions over time
When a pathogen enters the body, cells in the blood and lymph detect the specific pathogen-associated molecular patterns (PAMPs) on the pathogen's surface. The immune system can be activated by a lot of different things that the body doesn't recognize as its own. These are called antigens. Examples of antigens include the proteins on the surfaces of bacteria, fungi and viruses. ... Sometimes the immune system mistakenly thinks that the body's own cells are foreign cells. Antigens are proteins that are found on the surface of the pathogen. ... The antibodies destroy the antigen (pathogen) which is then engulfed and digested by macrophages. White blood cells can also produce chemicals called antitoxins which destroy the toxins (poisons) some bacteria produce when they have invaded the body.
hope this helps :))
-ari.