MLS 1114 Unit 2 Exam

Hematopoiesis

The formation of blood cells in the body.

Homeostasis

The maintenance of a stable internal environment in the body.

Apoptosis

Programmed cell death, a normal part of cell lifecycle.

Necrosis

Uncontrolled cell death due to injury or disease.

Definitive Erythropoiesis

The process of red blood cell formation in the bone marrow.

Medullary Hematopoiesis

Blood cell production in the bone marrow.

Extramedullary Hematopoiesis

Blood cell production outside the bone marrow (e.g., spleen, liver).

Osteoblast

A cell that secretes the matrix for bone formation.

Osteoclast

A cell that absorbs bone tissue.

Hyperplastic Bone Marrow

Bone marrow with increased cellularity, often due to increased cell production.

Hypoplastic Bone Marrow

Bone marrow with decreased cellularity, often due to decreased cell production.

Culling (Spleen)

The process by which the spleen removes damaged or old red blood cells from the circulation.

Pitting (Spleen)

The process by which the spleen removes inclusions or abnormalities from red blood cells without destroying the cell itself.

Hypersplenism

A condition characterized by an enlarged spleen and a reduction in one or more cell lines (red blood cells, white blood cells, platelets).

Splenomegaly

Enlargement of the spleen.

Cell Differentiation

The process by which a cell becomes specialized in structure and function.

Cell Commitment

The stage in cell development when a cell's fate is restricted to a specific lineage.

Cell Maturation

The process by which a cell progresses through its developmental stages to become fully functional.

Cytokines/Chemokines

Signaling molecules that regulate cell maturation and differentiation in hematopoiesis.

EPO (Erythropoietin)

A hormone produced by the kidneys that stimulates red blood cell production.

Reticulocyte

An immature red blood cell that contains residual RNA.

Reticulocytosis

An increased number of reticulocytes in the peripheral blood, indicating increased red blood cell production.

Polychromatic Erythrocyte

An immature red blood cell that stains bluish-gray with Wright stain due to the presence of RNA.

Hemolysis

The destruction of red blood cells.

Extravascular Hemolysis

The destruction of red blood cells outside of the blood vessels, typically by macrophages in the spleen or liver.

Intravascular Hemolysis

The destruction of red blood cells within the blood vessels.

Anemia

A condition characterized by a deficiency of red blood cells or hemoglobin in the blood, resulting in reduced oxygen-carrying capacity.

Acanthocyte

A red blood cell with irregularly spaced, thorn-like projections.

Echinocyte

A red blood cell with evenly spaced, short, blunt projections; also known as a burr cell.

Pappenheimer Bodies

Small, irregular granules of iron within red blood cells.

Basophilic Stippling

The presence of small, blue-staining granules (RNA) within red blood cells.

Microcytic Anemia

Anemia characterized by small red blood cells (low MCV).

Macrocytic Anemia

Anemia characterized by large red blood cells (high MCV).

Intrinsic Erythrocyte Defect

A defect within the red blood cell itself that leads to its premature destruction or dysfunction.

TIBC (Total Iron Binding Capacity)

A measure of the blood's capacity to bind iron with transferrin.

IDA (Iron Deficiency Anemia)

Anemia caused by insufficient iron to produce hemoglobin.

ACD (Anemia of Chronic Disease)

Anemia associated with chronic inflammatory, infectious, or malignant conditions.

Sideroblastic Anemia

Anemia characterized by the presence of ringed sideroblasts in the bone marrow.

Thalassemia

A group of inherited blood disorders characterized by decreased or absent production of globin chains. Microcytic

Hemoglobinopathy

A genetic defect that results in abnormal structure of one of the globin chains of the hemoglobin molecule.

Intrinsic Factor

A protein produced in the stomach that is necessary for the absorption of vitamin B12.

HDFN (Hemolytic Disease of the Fetus and Newborn)

A type of anemia that occurs when the mother's antibodies attack the red blood cells of the fetus or newborn.

MAHA (Microangiopathic Hemolytic Anemia)

A type of anemia caused by the destruction of red blood cells as they pass through damaged small blood vessels.

Aplastic Anemia

A condition in which the bone marrow fails to produce enough blood cells.

Megaloblastic Anemia

A type of macrocytic anemia, B12, Folate, Neoplasm, hypersegmented neutrophils

Ineffective Erythropoiesis

The production of defective red blood cells that are prematurely destroyed in the bone marrow.

Insufficient Erythropoiesis

A decreased production of red blood cells due to various factors.

Hypoproliferative Anemia

Anemia due to decreased red blood cell production.

Define Hematopoiesis

The process of maintain an adequate supply of red blood cells

Define homeostasis

A ballance between cellular proliferation, differentiation, and apoptosis

Define apoptosis

Preprogrammed cell death

What is apoptosis role in the cell lifecycle

Helps eliminate excess cells, old, abnormal, or infected cells

can be induced by other cells

Define necrosis

A cell that is dying by non-natural means (ie: burn your arm)

Where does definitive erythropoiesis occur

Primarily in the bone marrow after birth, and in the yolk sac, liver, and spleen during embryonic development.

The formation of what cell indicates definitive erythropoiesis?

Where does hematopoiesis happen during 18 days gestation?

Requires oxygen from mom, fetal hemoglobin, yolk sack

Where does hematopoiesis happen during childhood?

In the bone marrow, all bone marrow is active red marrow

Where does hematopoiesis happen during adulthood?

End of long bones, pelvis, skull, ribs, sternum, scapula, vertebrae, clavicles

Define primitive erythropoiesis

The process of blood cell formation occurring in the yolk sac during early embryonic development, primarily producing primitive red blood cells.

Define definitive erythropoiesis

the process of forming red blood cells from definitive erythroid progenitors, primarily occurring in the bone marrow during fetal development and after birth.

Define medullary hematopoiesis

Hematopoiesis in the bone marrow

Define extramedullary hematopoiesis

Hematopoiesis outside of the bone marrow

What is the difference between medullary and extra medullary hematopoiesis?

Medullary hematopoiesis occurs in the bone marrow, while extramedullary hematopoiesis takes place outside the bone marrow, often in organs like the spleen or liver.

What are the common sites of extramedullary hematopoiesis?

Common sites include the spleen, liver, and lymph nodes.

What is the only cell that can divide?

lymphocytes

How many RBCs per day do you make?

200 billion

How many WBCs and plts do you make per day?

100 billion

Where does hematopoiesis happen at 3 months gestation

Primarily the liver, also activity in the kidneys and lymphoid tissue

Where does hematopoiesis happen at 6 months gestation?

Shifts from organs to bone marrow

Define bone marrow hyperplasia

An increase in the production of blood cells in the bone marrow, often in response to increased demand or underlying conditions.

Describe the composition of bone marrow

Bone marrow is composed of hematopoietic stem cells, supportive stromal cells, adipocytes, and extracellular matrix components, facilitating blood cell production and maintenance.

Define the hematopoietic environment

The hematopoietic environment refers to the specialized microenvironment within the bone marrow that supports the growth, differentiation, and function of hematopoietic stem cells and progenitor cells, ensuring effective hematopoiesis.

What are the three main stromal cells?

Fibroblasts, adipocytes, macrophages

Macrophages

Productions of cytokines to stimulate cell development

Adipocytes

Cells that produce fatty bone marrow

Fibroblasts

makes connective tissue cells that produce collagen and extracellular matrix components.

Define osteiblast

Bone-forming cells that produce new bone matrix and play a key role in mineralization.

Define osteoclast

Cells that break down bone tissue.

Define hyperplastic bone marrow

An increase in the number of hematopoietic cells in the bone marrow, often in response to increased demand for blood cell production. Can lead to pathologic fractures

What causes hyperplastic bone marrow?

Anemia, Infection, Leukemia

Define hypoplastic bone marrow

A condition characterized by a decrease in the number of hematopoietic cells in the bone marrow, resulting in reduced blood cell production.

What causes hypoplastic bone marrow

A reduction in the production of blood cells due to decreased or absent hematopoietic cells in the bone marrow, which can lead to conditions like aplastic anemia.

What are the primary lymphoid organs?

The primary lymphoid organs are the bone marrow and thymus, where lymphocytes are produced and mature. No antigen activity

What are the secondary lymphoid organs?

Spleen, lymph nodes. Antigen dependent lymphopoiesis

What type of lymphocytes does the bone marrow make?

B cells

What type of lymphocytes does the thymus make?

T cells

What does the thymus do in hematopoiesis

The thymus plays a crucial role in hematopoiesis by maturing T cells, which are essential for adaptive immunity. Antigen dependent, well defined in children but atrophied in adults

What does the spleen do?

Its a secondary lymph organ, culls or pits RBCs, is a reservoir for RBCs and plts

How does the spleen stress RBCs?

It makes them squeeze through very small areas, with hypoglycemia, and hypoxia

Define differentiation

Differentiation is the process by which unspecialized cells develop into specialized cell types with distinct functions. Become different by allowing the expression of certain genes while restricting others

Define commitment

The process by which hematopoetic cell genetically commits to a certain cell type, controlled by CSFs

Define maturation

Maturation is the process by which committed cells undergo further changes and acquire the characteristics necessary for their specific functions, completing their development into fully functional cell types.

Define culling

Culling is the process of eliminating or removing cells that are damaged, nonfunctional, or not required, often to maintain healthy cell populations.

Define pitting

Pitting is the process whereby spleen macrophages remove remnants of red blood cells that have undergone senescence or damage, helping to maintain healthy blood cell populations.

What three things are needed to diagnose hypersplenism

A decrease in blood cell counts, evidence of splenic enlargement, and elevated splenic function tests.

Define splenomegaly

Splenomegaly is the abnormal enlargement of the spleen, often associated with various medical conditions such as infections, liver diseases, or blood disorders.

What conditions cause splenomegaly

Splenomegaly can be caused by various conditions including infections, liver diseases, hematologic disorders, and malignancies.

List the maturation of RBCs in order with old nomenclature

Rubriblast, prorubricyte, rubricyte, metarubricyte, reticulocyte, erythrocyte.

List the maturation of RBCs in order with new nomenclature

Pronormoblast, basophilic normoblast, polychromatic normoblast, orthochromatic normoblast, reticulocyte, erythrocyte.