BLOOD

Comprehensive vocabulary flashcards covering blood regulation and protection roles, plasma composition, hematopoiesis, red blood cell synthesis and breakdown, leukocyte types and functions, and thrombocyte mechanisms.

Buffers

compounds in the blood that keep pH stable by weakening strong acids or bases.

Centrifugation

A process that separates blood components based on their density by spinning a blood sample at high speeds in a centrifuge.

Plasma

The liquid portion of blood, making up $55\text{ }\text{\%}$ of total blood volume.

Buffy Coat

The thin middle layer formed during blood centrifugation that contains white blood cells (WBCs) and platelets.

Albumin

The smallest and most numerous plasma protein; helps maintain osmotic pressure essential for fluid exchange across blood capillary walls.

Globulin

A class of plasma proteins that includes immunoglobulins (antibodies) that attack pathogens, as well as alpha and beta globulins that transport iron.

Fibrinogen

A large plasma protein that plays an essential role in blood clotting.

Haematopoiesis

The process of producing blood cells; begins before birth in the yolk sac, moves to the liver, spleen, thymus, and lymph nodes,

red bone marrow becoming the primary site during the last $3\text{ }\text{months}$ of pregnancy and throughout life.

Pluripotent Stem Cell

A precursor cell located in the bone marrow that differentiates into myeloid stem cells or lymphoid stem cells to generate all formed elements of the blood.

Erythropoiesis

The process of producing red blood cells in the red bone marrow, starting from a proerythroblast and maturing into a functional red blood cell.

Reticulocyte

An immature erythrocyte that has ejected its nucleus, has a biconcave shape, which enters the bloodstream and matures into a red blood cell within $1\text{ }\text{to}\text{ }2\text{ }\text{days}$.

Erythropoietin (EPO)

A hormone produced and released by the kidneys in response to hypoxia (low oxygen levels) that speeds up erythrocyte production in red bone marrow.

Creates a negative feedback loop

Haemoglobin

A protein inside erythrocytes composed of $2\text{ }\text{alpha}$ chains and $2\text{ }\text{beta}$ chains, each containing a central iron ($\text{Fe}^{2+}$) haem group that can bind $1\text{ }\text{molecule}$ of oxygen (totaling $4\text{ }\text{oxygen}$ molecules per haemoglobin).

Transferrin

A transport protein that binds iron released from recycled haemoglobin so it can be stored or reused in the red bone marrow for new red blood cell production.

Stercobilin

A breakdown product of bilirubin created by bacteria in the large intestine that gives faeces its characteristic color.

Neutrophil

A granular leucocyte

with a multilobed nucleus that performs phagocytosis by engulfing bacteria into a phagosome and destroying them.

Eosinophil

A granular leucocyte with a bilobed nucleus that targets antibody-marked parasites (such as worms) by attaching to their surface and undergoing degranulation to release toxic ROS

Basophil

A granular leucocyte that binds IgE antibodies and undergoes degranulation during allergic reactions to release histamine, prostaglandins, cytokines, and heparin.

Histamine

A chemical mediator released by basophils that causes blood vessels to widen and become leaky, resulting in tissue redness, swelling, and itching.

Heparin

substance released by basophils that prevents blood clotting within an inflamed area.

Monocyte

An agranular leucocyte that circulates in the blood before migrating into tissues to differentiate into macrophages

B Lymphocyte

An agranular lymphocyte that differentiates into plasma cells to produce antibodies that bind to germs and mark them for destruction.

Helper T Cell

A type of lymphocyte that coordinates immune responses by sending signaling molecules called cytokines.

Killer T Cell

A type of cytotoxic lymphocyte that destroys virus-infected cells and cancer cells using specialized enzymes.

Thrombocytes

Platelets derived from megakaryocytes that contain clotting chemicals and surface proteins that allow them to change shape and stick to damaged blood vessels.