The remains or impression of a prehistoric organism preserved in petrified form or as a mold or cast in rock.
Mold fossils
Cast fossils
Trace fossils
B cells mature in the bone marrow, which is at the core of most bones It recognises invaders by the shape of molecules -antigens- on their surfaces. With the help of T cells, B cells make proteins called antibodies. The antibodies will help your body become aware of intruders.
Animal dander would be the answer you're looking for.
Hope this helps :)
Hello, I figured your question was missing its options so I went online to find them. Here they are:
The process of phagocytosis involves all of the following EXCEPT
:
a. adhesion.
b. secretion of cytotoxins.
c. elimination.
d. vesicle fusion.
e. chemotaxis.
Answer:
The correct answer is: b) secretion of cytotoxins.
Explanation:
Phagocytosis is a mechanism performed by cells in which the plasma membrane engulfs a large particle. Phagocytosis is used by cells in the immune system to ingest pathogens like viruses and bacteria.
Phagocytosis consists of many steps:
- activation
- the phagocytes that were resting are activated in the inflammatory response when a pathogen enters the body.
- chemotaxis - this refers to the process in which the phagocyte moves to the pathogen by following the chemical factors released by these germs.
- adhesion - the phagocyte attaches to the pathogen.
- ingestion
/vesicle fusion - the phagocyte sends pseudopods to engulf the pathogen, and places it in a phagosome, which is an endocytic vesicle. The phagosome and the phagocyte will fuse so the pathogen gets inside.
- elimination - the pathogen is destroyed in the phagocyte by the lysosomes present in it.
<u>The</u><u> secretion of cytotoxins</u><u> is not a part of the phagocytosis, and is a process exclusive to </u><u>T cells</u><u> (leukocytes that lack the ability to phagocyte).</u>
