Immunity

The cells of the immune system originate from the bone marrow. The bone marrow is a soft tissue found inside the bones and is responsible for producing various types of blood cells, including the cells of the immune system. These immune cells, such as white blood cells, play a crucial role in defending the body against infections and diseases. Therefore, the bone marrow is the correct answer as it is the primary source of immune cell production.

Phagocytes and lymphocytes are two groups of cells involved in defense. Phagocytes are responsible for engulfing and destroying pathogens through a process called phagocytosis. They are part of the innate immune system and include cells like neutrophils and macrophages. Lymphocytes, on the other hand, are part of the adaptive immune system and play a crucial role in recognizing and targeting specific pathogens. They include B cells, which produce antibodies, and T cells, which directly attack infected cells. Together, phagocytes and lymphocytes work to protect the body against pathogens and maintain immune homeostasis.

Antigens are substances that can trigger an immune response in the body. When antigens enter the body, they stimulate the immune system to produce an immune response, which includes the production of antibodies and activation of immune cells. This immune response is essential for the body to recognize and eliminate foreign substances, such as bacteria or viruses. Therefore, the correct answer is "Stimulate the immune response."

Phagocytosis is the cellular process in which solid particles are engulfed by the cell membrane. It is a form of endocytosis that involves the ingestion of large particles or microorganisms by specialized cells called phagocytes. During phagocytosis, the cell extends its membrane around the particle, forming a phagosome. The phagosome then fuses with lysosomes, which contain enzymes that break down the ingested material. This process is important for immune defense, as phagocytes can engulf and destroy pathogens or cellular debris.

Memory cells are stored in the blood for many years. These cells are a type of immune cell that are formed after an initial infection or vaccination. They "remember" the specific pathogen and are able to mount a faster and stronger immune response if the same pathogen is encountered again in the future. This long-term storage of memory cells in the blood allows for a quicker and more efficient immune response upon re-exposure to a particular pathogen.

The measures mentioned (improvement in clean water supply, sewage treatment, insect control, and milk pasteurization) primarily target diseases that are transmitted through contaminated water, insects, or food. Cholera, malaria, and tuberculosis can all be reduced by these measures as they are directly or indirectly related to these modes of transmission. However, HIV/AIDS is primarily transmitted through sexual contact, sharing needles, or mother-to-child transmission, and is not directly affected by these measures. Therefore, HIV/AIDS will not be reduced by the mentioned improvements in the village.

The correct answer is "Primary and Secondary response." This is because the question is asking about the two types of response, and the options provided are "Active and Passive response," "Primary and Secondary response," "Tertiary and Quaternary response," and "Secondary and Tertiary response." Among these options, "Primary and Secondary response" is the only one that directly addresses the question by providing two distinct types of response. The other options either provide different types of response or do not provide two distinct types of response.

The use of antibiotics in animal feed can lead to the development of antibiotic resistance in pathogenic bacteria. This means that these bacteria can become resistant to the antibiotics, making them ineffective in treating human diseases caused by these bacteria. This is a major concern as it limits the options for effective treatment and can lead to the spread of antibiotic-resistant infections.

T cells are responsible for coordinating the immune response by stimulating B cells to divide and secrete antibodies into the blood. T cells recognize antigens presented by antigen-presenting cells and activate B cells, which then undergo clonal expansion and produce antibodies specific to the pathogen. T cells play a crucial role in adaptive immunity and help in eliminating pathogens from the body.

Antibodies are proteins that are produced by the immune system in response to the presence of foreign substances in the body. They are specifically classified as globular glycoproteins because they have a three-dimensional, globular shape and contain carbohydrate molecules attached to the protein structure. This glycosylation is important for the functioning of antibodies, as it helps in their stability, solubility, and recognition of foreign antigens. Therefore, the correct answer is "Globular glycoproteins."