Hematopoietic Stem Cells and Embryonic Hematopoiesis (Vocabulary)

Vocabulary flashcards covering stem cells and embryonic hematopoiesis as discussed in the notes.

Stem cell

A primitive, immature cell that can differentiate into various cell types in response to stimuli.

Differentiation

Process by which a stem cell becomes a more specialized cell type.

Self-renewal

Capability of a stem cell to clone itself and maintain the stem cell pool.

Hematopoietic stem cell (HSC)

The earliest stem cell in blood formation; can self-renew or differentiate into myeloid or lymphoid lineages.

Myeloid lineage

Blood cell lineage from HSC that can give rise to erythrocytes, granulocytes, monocytes, and megakaryocytes.

Lymphoid lineage

Blood cell lineage from HSC that gives rise to lymphocytes.

Common myeloid progenitor (CMP)

Progenitor giving rise to myeloid cells such as erythrocytes, granulocytes, monocytes, and megakaryocytes.

Common lymphoid progenitor (CLP)

Progenitor giving rise to lymphoid cells (lymphocytes).

Erythroblast

Young red blood cell precursor produced in embryonic hematopoiesis.

Yolk sac / mesoblastic phase

Early embryonic hematopoiesis beginning around 19 days after fertilization, with abundant erythroblasts.

Hepatic phase

Fetal liver and spleen stage (2–7 months) of hematopoiesis; liver becomes a major site of production.

Medullary phase (bone marrow phase)

Final embryonic phase where hematopoiesis occurs in bone marrow.

Bone marrow

Cavities within bones where hematopoietic cells are produced in adulthood.

Erythrocyte

Red blood cell; derived from the erythroid lineage and carries oxygen.

Lymphocyte

A lymphoid cell produced from CLP differentiation.

Granulocyte

A myeloid-derived cell type including neutrophils, eosinophils, and basophils.

Megakaryocyte

A large bone marrow cell that gives rise to platelets.

Adult hematopoiesis

Hematopoiesis that occurs throughout life, primarily in the bone marrow.