Answer:
The correct answer is option A. "The contents of blood come into closer contact with tissues in a closed system than an open system".
Explanation:
In a closed circulatory system, the blood has an specific path, circulating from arteries to veins and to smaller blood vessels throughout the body. This is in contrast with open circulatory systems at which the blood is not contained in arteries or veins but it suffuses the body. A closed circulatory system have many advantages over open circulatory system, however in a closed circulatory system the contents of blood are not into closer contact with tissues in than an open system. Actually, in an open circulatory system the blood is in closer contact with tissues.
I believe they cannot start with big trees and bushes because the there is not enough nutrients in the soil, so instead pioneer species pave the way for primary succession.
Answer:
Parasympathetic nervous system effects are slow or inhibit function, where is sympathetic, is responsible for the intense physical activity.
Explanation:
The autonomic nervous system or ANS is divided into 2 distinct systems on the basis of their effects- the parasympathetic nervous system and the sympathetic nervous system.
Both of these have opposite actions on the functions that they maintain.
The sympathetic nervous system regulates the body for a high level of physical activity and also known as fight or flight. It fasts the functions of the body according to the situation.
The parasympathetic nervous system is having the opposite effect of the sympathetic nervous system slows high energy functions and relaxes the body.
Thus, the comparison of these nervous systems is mention above.
Professional antigen-presenting cells, such as phagocytes, are the first cells to encounter a pathogen (apcs). This means they have the ability to activate cells of the adaptive immune system.
<h3>What is meant by Pathogen?</h3>
- A pathogen is an organism that infects its host with disease, and the severity of the disease symptoms is referred to as virulence.
- Pathogens include viruses, bacteria, unicellular and multicellular eukaryotes, and a wide range of other organisms.
- The bone marrow of an average healthy adult generates 100 billion new neutrophils per day. Because there are so many neutrophils in the body at any given time, they are often the first cells to reach the site of an infection.
- Long thought to be a component of the innate immune system, complement has recently emerged as an important regulator of the adaptive immune response.
Therefore the correct option is D) can activate cells of the adaptive immune system.
To learn more about Pathogen, refer to:
brainly.com/question/1008643
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