Human Anatomy & Physiology II - Topic 1

Formed elements

Cellular components of blood; that is, erythrocytes, leukocytes, and platelets

Red blood cells (RBCs)

(Also, erythrocytes) one of the formed elements of blood that transports oxygen

White blood cells (WBCs)

(Also, leukocytes) one of the formed elements of blood that provides defense against disease agents and foreign materials

Platelets

(Also, thrombocytes) one of the formed elements of blood that consists of cell fragments broken off from megakaryocytes

Plasma

in blood, the liquid extracellular matrix is composed mostly of water that circulates the formed elements and dissolved materials throughout the cardiovascular system

Functions of Blood

1. Transportation 2. Defense 3. Maintenance of Homeostasis

Hematocrit

(Also, packed cell volume) volume percentage of erythrocytes in a sample of centrifuged blood

Buffy coat

A thin, pale layer of leukocytes and platelets separates the erythrocytes from the plasma in a sample of centrifuged blood

Centrifugation

A laboratory technique that separates components of a mixture based on their density using high-speed rotation

Anemia

a medical condition characterized by a deficiency of red blood cells or hemoglobin, leading to reduced oxygen transport in the body

Matrix

refers to the extracellular substance in which cells are embedded, providing structural and biochemical support to the surrounding cells

Characteristics of Blood

1. Color

2. Viscosity

3. Temperature

4. pH and Buffers

5. Volume and Body Weight

Plasma proteins

1. Albumin

2. Globulins

3. Fibrinogen

Albumin

most abundant plasma protein, accounting for most of the osmotic pressure of plasma

Globulins

the heterogeneous group of plasma proteins that includes transport proteins, clotting factors, immune proteins, and others

Fibrinogen

plasma protein is produced in the liver and involved in blood clotting

Viscosity

the thickness or resistance to flow of a fluid, influenced by its internal friction

Nonspecific immunity

the body's general defense mechanisms that protect against a wide range of pathogens

Hemopoiesis

is the process of blood cell formation in the bone marrow, giving rise to red blood cells, white blood cells, and platelets, essential for maintaining the body's blood composition and function

Lymphoid stem cells

type of hematopoietic stem cells that give rise to lymphocytes, including various T cells, B cells, and NK cells, all of which function in immunity

Lymphocytes

A type of white blood cell that make antibodies to fight off infections

Myeloid stem cells

gives rise to some formed elements, including erythrocytes, megakaryocytes that produce platelets, and a myeloblast lineage that gives rise to monocytes and three forms of granular leukocytes (neutrophils, eosinophils, and basophils)

Neutrophils

the most numerous of the leukocytes; especially active against bacteria

Eosinophils

they release antihistamines and are especially active against parasitic worms

Basophils

store histamine and heparin

Memory cells

long-lived immune cells that "remember" previous encounters with pathogens, enabling a faster and more effective immune response upon re-exposure

Yolk sac

an extraembryonic membrane in early development that plays a vital role in providing nutrients to the developing embryo and serves as an initial site for blood cell formation

Fetus

the developmental stage of an embryo after the eighth week of gestation until birth, characterized by the growth and maturation of organ systems

Erythropoietin (EPO)

glycoprotein triggers the bone marrow to produce RBCs; secreted by the kidney in response to low oxygen levels

Thrombopoietin

hormone secreted by the liver and kidneys that prompts the development of megakaryocytes into thrombocytes (platelets)

Cytokines

class of proteins that act as autocrine or paracrine signaling molecules; in the cardiovascular system, they stimulate the proliferation of progenitor cells and help to stimulate both nonspecific and specific resistance to disease

Colony-stimulating factors (CSFs)

glycoproteins that trigger the proliferation and differentiation of myeloblasts into granular leukocytes (basophils, neutrophils, and eosinophils)

Interleukins

signaling molecules that may function in hemopoiesis, inflammation, and specific immune responses

Hematopoiesis

is the process of blood cell formation in the bone marrow, giving rise to red blood cells, white blood cells, and platelets, essential for maintaining the body's blood composition and function

Glycoprotein Hormone

a hormone consisting of a protein linked to carbohydrate (glycan) chains

Fibroblasts

connective tissue cells responsible for producing extracellular matrix components like collagen and essential for tissue repair and maintenance

Progenitor Cells

intermediate or partially specialized cells that can give rise to specific types of mature cells within a particular tissue or organ

Erythrocyte

mature myeloid blood cell that is composed mostly of hemoglobin and function primarily in the transportation of oxygen and carbon dioxide

Formed Element

components of blood that are cellular in nature, including erythrocytes, leukocytes, and platelets

Biconcave

refers to a concave shape on both sides, such as the shape of erythrocytes (red blood cells), which are flattened and indented on both surfaces

Mitochondria

double-membraned organelles responsible for producing energy (ATP) in eukaryotic cells through cellular respiration

Heme

red, iron-containing pigment to which oxygen binds in hemoglobin

Globin

heme-containing globular protein that is a constituent of hemoglobin

Bilirubin

yellowish bile pigment is produced when iron is removed from heme and is further broken down into waste products

Biliverdin

green bile pigment is produced when the non-iron portion of heme is degraded into a waste product; converted to bilirubin in the liver

Trace elements

these are chemical elements that are present in very small amounts (usually less than 0.01% of total body weight) in living organisms but are essential for various physiological functions

EPO (Erythropoietin)

a glycoprotein hormone that plays a crucial role in the regulation of erythropoiesis

Polycythemia

excessive immature erythrocyte production

Leukocyte

(also, white blood cell) colorless, nucleated blood cell, the chief function of which is to protect the body from disease

Natural killer (NK) cells

cytotoxic lymphocytes capable of recognizing cells that do not express "self" proteins on their plasma membrane or that contain foreign or abnormal markers; provide generalized, nonspecific immunity

B cells

produce antibodies for humoral immunity

T cells

engage in cellular-level immunity

Leukopenia

below-normal production of leukocytes

Leukocytosis

a medical condition characterized by an elevated number of white blood cells in the bloodstream, often indicative of infection, inflammation, or other underlying health issues

Leukemia

type of cancer that affects the blood and bone marrow, characterized by the overproduction of abnormal white blood cells, impairing the body's ability to fight infections and perform normal blood functions

Lymphoma

form of cancer in which masses of malignant T and/or B lymphocytes collect in lymph nodes, the spleen, the liver, and other tissues

Spleen

an essential blood organ, filters and stores blood cells, actively engaging in immune responses and housing platelets for clotting

Thymus

plays a pivotal role in the development and maturation of T lymphocytes, central to specific immune reactions

Histamines

signaling molecules released by cells in response to injury, allergic reactions, or inflammation

Thrombocytosis

condition in which there are too many platelets, resulting in abnormal clotting (thrombosis)

Growth Factors

some cytokines or hormones that are the key players in regulating cell growth, tissue repair, and immune responses

Hemostasis

the process by which the body seals a ruptured blood vessel and prevents further loss of blood

Vascular spasm

initial step in hemostasis, in which the smooth muscle in the walls of the ruptured or damaged blood vessel contracts

Platelet plug

accumulation and adhesion of platelets at the site of blood vessel injury

Hemorrhage

refers to the escape or loss of blood from the circulatory system, often due to a rupture or injury to blood vessels, and can occur internally or externally

Smooth Muscles

involuntary, non-striated muscles found in the walls of internal organs, vessels, and structures

Coagulation

formation of a blood clot; part of the process of hemostasis

Extrinsic pathway

the initial coagulation pathway begins with tissue damage and results in the activation of the common pathway (initiated by trauma)

Intrinsic pathway

initial coagulation pathway that begins with vascular damage or contact with foreign substances, and results in the activation of the common pathway (starts in the bloodstream due to vessel wall damage)

Fibrinolysis

it is the natural process of breaking down blood clots in the body, involving the dissolution of fibrin, a protein involved in clot formation, to maintain blood vessel health and prevent excessive clotting

Antithrombin

an anticoagulant that inactivates factor X and opposes the conversion of prothrombin (factor II) into thrombin in the common pathway

Heparin

short-acting anticoagulant stored in mast cells and released when tissues are injured opposes prothrombin

Hemophilia

it is a genetic disorder characterized by inadequate synthesis of clotting factors

Thrombosis

the formation or presence of a blood clot (thrombus) within a blood vessel, which can obstruct blood flow and potentially lead to serious medical complications

Mural Thrombus (Large Vessel)

• Adheres to the vessel wall

• Reduces blood flow

Occlusive Thrombus (Small Vessel)

• Completely blocks blood flow

• Occurs in small vessels

Cascade

a sequential series of events in which one event triggers the next

Genetic Disorder

an inherited condition resulting from abnormalities in an individual's DNA or genes

Antigen

molecules recognized by the receptors of B and T lymphocytes

Antibodies

proteins produced by specialized B lymphocytes that protect the body by binding to foreign objects such as bacteria and viruses

Agglutination

clustering of cells into masses linked by antibodies

Hemolysis

destruction (lysis) of erythrocytes and the release of their hemoglobin into circulation

ABO blood group

blood-type classification is based on the presence or absence of A and B glycoproteins on the erythrocyte membrane surface

Transfusion

the process of transferring blood or blood products from one person (the donor) to another person (the recipient)

B lymphocytes (B cells)

immune cells that produce antibodies