Answer:
a. antigen
Explanation:
The Immune system is composed of immune cells that defend the body against foreign substances such as bacteria or virus. Lymphocytes (B and T cells) are one of the main immune cells
Lymphocytes have the ability to recognize and bind to antigens, wich are substances foreign to the body ( i.e bacterial or virus elements) that evokes an immune response.
I think burgess shells would be the answer
Answer: Gastrocholic reflex
Explanation:
The gastrocholic reflex or gastrocolic response is one of the physiological reflexes in the stomach which controls the movements like peristalsis and motility in the gastrointestinal tract.
This reflex is generated by the the food particles that enters the stomach. The bolus of the food in the stomach helps in the mass movement of the other food particles in the colon.
This reflex is known as gastrocholic reflex.
Answer:
A considerable increase in phytoplankton populations in winter, and a greater increase in spring due to increase in light intensity.
Explanation:
Nitrogen and phosphorus are important nutrients required by phytoplankton populations. The growth of phytoplankton populations is dependent on the level of the availability of Nitrogen and Phosphorus in the presence of sunlight.
A rise in the aquatic coastal levels of nitrogen and phosphorus would result in a great increase in phytoplankton populations in spring, as stimulated by nutrient enrichment coupled with the availability of sunlight during spring. Phytoplankton populations would increase also in winter but not as high when compared to the rise in population in spring
