HLA Molecules Expressed on Cell Membranes Can Range from Three

question 8

Multiple Choice

HLA molecules expressed on cell membranes can range from three to twelve because

• A) all six maternal and paternal genes are expressed
• B) there are three genes that code for HLA class I molecules
• C) most cells do not express HLA class II molecules
• D) all of the above

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Definitions:

Embryo

An early stage of development in multicellular organisms following fertilization and before fetal stage, showing initial formation of organs and structures.

Cotyledon(s)

Cotyledons are the first leaves that appear from a germinating seed, playing a crucial role in photosynthesis and the storage of nutrients during the early stages of plant development.

Tissue Culture

Tissue culture is a technique of growing tissues or cells in an artificial medium outside their original body for the purposes of research or medical treatment.

Meristem

Regions of plant tissue consisting of undifferentiated cells capable of cell division, responsible for the growth and development of plant organs.