Read the passage carefully and answer the questions given below.
Our immune system plays the major role in preventing diseases when we are exposed to disease-causing agents. Immunity is of two types: (i) Innate immunity and (ii) Acquired immunity. The human immune system consists of lymphoid organs, tissues, cells and soluble molecules like antibodies. The immune system also plays an important role in allergic reactions, auto-immune diseases and organ transplantation. The primary lymphoid organs are bone marrow and thymus. The secondary lymphoid organs are spleen, lymph nodes, tonsils, Peyer's patches of small intestine and appendix. There is lymphoid tissue also located within the lining of the major tracts (respiratory, digestive and urogenital tracts) called mucosa associated lymphoid tissue (MALT). It is important to note that HIV/AIDS is not spread by mere touch or physical contact it spreads only through body fluids. AIDS has no cure, prevention is the best option. Adolescence is accompanied by several biological and behavioural changes and surveys and statistics show that use of drugs and alcohol has been on the rise especially among the youth. Factors associated with drug and alcohol abuse among adolescents are a child's natural curiosity, stress, the perception among youth that it is 'cool' or progressive to smoke, media exposure and an unstable or unsupportive family structures and peer pressure. It is best to identify the situations that may push an adolescent towards use of drugs or alcohol, and to take remedial measures well in time.
Mucosa associated lymphoid tissue is absent in the -
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Skeletal system
Mucosa associated lymphoid tissue (MALT) is lymphoid tissue in the lining of the major tracts that open to the outside. Microbes enter the body through these tracts, so MALT guards them. It makes up about 50 per cent of the lymphoid tissue in the human body.
Option (1) Respiratory tract — Has MALT.
Option (2) Urogenital system — Has MALT.
Option (3) Digestive tract — Has MALT.
Option (4) Skeletal system — No MALT. Bones are not a tract with a mucous lining open to the outside.
Note: The passage is taken from NCERT. NTA has put lines of the NCERT text together to make it. Most CUET (UG) questions come straight from NCERT, so study the book line by line, including figures and their titles.