Answer:
Innate immunity is a non-specific immune system which provides defence against any pathogenic microorganism in early stages. It includes physical barrier such as skin, chemical barriers such as saliva, tears, et cetera, phagocytic cells such as macrophages, et cetera.
Acquired immune system is the one which develops after exposure to pathogen or antigen. It is highly specific in nature. It includes B-lymphocytes and T-lymphocytes. It includes the production of antibodies.
Vaccines are used to develop acquired immunity in people. The process is termed as vaccination or immunisation. Heat-killed or weakened pathogen or antigen is inserted into a person after which a person develops antibodies and memory cells against that pathogen or disease. So, the immune system acts more vigorously against that pathogen in secondary infection.
Thus, a person becomes immunised.
A fissure volcano does not form a mountain
Answer:
The tail and the caudal fin are the chief locomotory organs of fish and are used for rapid swimming during which tail is lashed from side to side by "alternate contraction and relaxation" of the myomeres on the two sides of the vertebral column.
Explanation:
<span>Bones are linked together at skeletal joints by </span>cartilage I believe.
Answer:
The distance between them is changing at the speed of 10.16 m/hr
Explanation:
Consider the sketch attached below.
The question is simply asking to calculate the resultant of the two velocities.
To get the angle between them, we simply use the coordinates of the two vectors to determine the angle between them.
90 + 45 = 135°
from the cosine rule we have
= 
+ 
- 2abcosθ
= 
+
- 2 ×6×5×cos 135
= 103.426
c = 
c = 10.17 m/hr
