Answer;
Antibodies.
The human immune system fights infection by releasing antibodies.
Explanation;
The immune system acts to defend the body against pathogens such as viruses, bacteria and fungi that may cause a disease.
It does so using various types of mechanism, one is by the production of antibodies.
Antibodies are proteins that are produced by the B-cell and are used by the immune system to identify and neutralize pathogens.
These antibodies also activates proteins known as complements which assist in the killing of bacteria, viruses and the infected cells.
Answer:
The polar bear is an animal which is prevalent in the arctic region of the world which is characterized by very cold icy climate.
They adapt to these climatic conditions by maintaining a body temperature of 37°C through its thick fur and tough skin. It also has an insulating fat layer (adipose tissues) which is very thick.
This insulation helps in keeping the animal very warm in extreme temperatures.
The first blank is organelles, the second blank is nucleus, the third blank is eukaryotes, the fourth blank is mitochondria, and the fifth blank is flagella.
Hope this helped!!
I guess that the endosperm is a unique tissue to the flowering plants. (It helps in their reproduction).
Answer:
The abiotic factors are the non-living parts of an ecosystem.
This includes rocks, water, metal etc.