Biology

Human Immunity and Blood

2,051 Questions

Human immunity and blood questions cover the physiological mechanisms protecting the body against diseases and the components of blood. Topics include blood groups, cell mediated immunity, monoclonal antibodies, and blood coagulation. These biology topics frequently appear in general science sections of competitive exams.

Blood groupsCell mediated immunityMonoclonal antibodiesBlood coagulationCancer immunology

Human Immunity and Blood Questions

Multiple choice

Stem cell factor is produced mainly by

  1. thymic epithelium

  2. the bone marrow stromal cells

  3. stem cell

  4. megakaryocytes

  5. reticuloendothelial system
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The bone marrow stromal cells comprise a complex mixture of cells including fibroblasts, macrophages and various other cell types. Stem cell factor (SCF) remains associated with the extracellular matrix and acts on primitive stem cells through a tyrosine kinase membrane receptor.

Multiple choice

The circulating plasma protein which participates in the initiation of blood coagulation is known as high molecular weight kininogen (HMWK). Which of the following is the other name of HMWK?

  1. FSF

  2. AHF

  3. Proaccerin

  4. Hageman factor

  5. Fitzgerald factor
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

High molecular weight kininogen is also known as Fitzerland factor. In the past, HMWK has been called HMWK-kallikrein factor, Flaujeac factor (1975), Fitzgerald factor (1975) and Williams-Fitzgerald-Flaujeac factor, the eponyms being for people first reported to have HMWK deficiency. Its current accepted name is to contrast it with low molecular weight kininogen (LMWK), which has a similar function to HMWK in the tissue (as opposed to serum) kinin-kallikrein system.