Answer: An antigen
Explanation:
A molecule that evokes immune response in the body of an organism is known as antigen. These substance can be protein, carbohydrates, lipids when asked for chemical nature.
Physically these substance can be dust particles, smoke, pollen grains, some food particles. Antigen can be defined as the substance that tends to produce immune response by the immune system of the body.
Hence, the correct answer is option D
3A- Negative feedback occurs when some function of the output of a system, process, or mechanism is fed back in a manner that tends to reduce the fluctuations in the output, whether caused by changes in the input or by other disturbances.
3B- Negative feedback loops are used to maintain homeostasis and achieve the set point within a system. Negative feedback loops are characterized by their ability to either increase or decrease a stimulus, inhibiting the ability of the stimulus to continue as it did prior to sensing of the receptor.
Hope I’ve helped ;)
Answer:
Whats the question? There isn't a question
Answer:
Cost Issue
Explanation:
Their funding hasn't been secured to repurpose the land.
