A cell, they are the tiniest living thing on earth.
Answer;
Endosymbiotic theory is important as it explains the origin of the chroloplast and mitochondria. It also explains the formation of the eukaryotic cells.
Explanation;
Endosymbiotic theory explains the origins of eukaryotic cell organelles such as mitochondria in animals and fungi and chloroplasts in plants.
Mitochondria and chloroplasts are believed to have developed from symbiotic bacteria, specifically alpha-proteobacteria and cyanobacteria, respectively.
White blood cells are made in the bone marrow. They are stored in your blood and lymph tissues. They help the body fight infection and other diseases.
Answer:
The secondary immune response is the immune response when the same antigen , memory cells that was encountered before is remembered and the immune system make antibodies to counter it.
Explanation:
There is a difference between the primary immune response and secondary immune response.
In the primary immune response occur when the immune system encountered an antigen for the first time which lead to the generation of memory cells and and the B cells with the T cells produce antibodies.
While the secondary immune response occur when the same antigen that was encountered the first time is encountered the second time and it lead to the stimulation of memory cells to produce more and high quantities of antibodies to fight foreign substances.