Biology 20 - Immune, Excretory, and Muscular Systems

Blood

A specialized body fluid that distributes heat and nutrients around the body

Plasma

The fluid component of the blood that carries blood cells and nutrients throughout the circulatory system; it composes about 55% of the blood

Albumin

A blood plasma protein that establishes and regulates osmotic pressure

Globulin

A blood plasma protein antibody that provides defense against foreign microbes

Erythrocyte

A red blood cell that contains hemoglobin whose primary purpose is to deliver oxygen around the body

Erythropoiesis

The process by which red blood cells are created, where nucleated stem cells in red bone marrow divide and shrink, eventually losing their nuclei

Oxyhemoglobin

Hemoglobin with oxygen attached

Anemia

A reduction of oxygen in the body attributable to lower levels of hemoglobin or poor production of erythrocytes

Leukocyte

A white blood cell whose primary purpose is to destroy pathogens and produce antibodies

Thrombocyte

An enucleated blood cell, also known as a platelet, which initiates the blood clotting process by releasing thromboplastin

Thromboplastin

A protein released by breaking thrombocytes which, alongside calcium ions, activates prothrombin

Prothrombin

The inactive precursor to thrombin

Thrombin

An enzyme which activates fibrinogen into fibrin

Fibrinogen

A blood plasma protein which is the inactive form of fibrin

Fibrin

A protein which forms a network of threads to form a thrombus when activated

Thrombus

A blood clot

Embolus

A dislodged thrombus that may lodge in a vital organ

Glycoprotein

A special marker on the cell membrane that allows for cell identification; dictates blood types

Antigen

A substance which stimulates the formation of antibodies

Agglutination

The process whereby cells clump due to antibodies attaching to cell antigens

Type A Blood

The blood type with A antigens and produces B antibodies

Type B Blood

The blood type with B antigens and produces A antibodies

Type O Blood

The blood type with no antigens and produces both A and B antibodies

Type AB Blood

The blood type with A and B antigens and produces no antibodies

Rhesus Factor

An antigen found on red blood cells, which is either positive or negative

Erythroblastosis Fetalis

A condition where incompatible parent blood types (mother is Rh- and father is Rh+) causes the mother’s blood to attack the child’s blood cells during birth

Phagocytosis

The cellular process where cells completely engulf and digest particles, including bacteria and cellular debris

Macrophage

A specialized leukocyte that employs phagocytosis as part of the immune system

Pseudopod

A protrusion of a macrophage used to attach to particles and facilitate phagocytosis

Neutrophil

A specialized leukocyte which is attracted to the chemical released in infected tissues

Chemotaxis

The directed movement of an organism in response to chemical stimuli

Lymphocyte

A leukocyte found in the bloodstream or in lymph nodes which are involved in the immune system

T Cell

A classification of leukocyte responsible for marking, killing, and remembering invaders

Thymus Gland

A lymphoid organ where T cells mature

B Cell

A classification of lymphocyte responsible for producing antibodies that target the antigens of invaders

Marker T Cell

A T cell which is responsible for identifying and marking foreign substances and invaders

Killer T Cell

A T cell which is responsible for puncturing the cell membrane of foreign invaders (e.g. bacteria)

Suppressor T Cell

A T cell which is responsible for suppressing the activity of killer T cells

Memory T Cell

A T cell which is responsible for remembering the identity of foreign substances and invaders

Memory B Cell

A B cell which is responsible for remembering the “recipes” of antibodies that aid in the agglutination of undesirable particles and cells

Antibody

A Y-shaped protein complementary to a particular antigen

Allergy

An negative immune response to a harmless substance

Autoimmune Disease

A disease where the immune system attacks the body’s cells

Organ Transplant Rejection

Where the immune system attacks a transplanted organ

Pluripotent Cell

A cell which can develop into multiple specialized cells

Osmolarity

The concentration of solute particles in a solution, measured in milliosmoles/litre (mosm/L)

Hyperosmotic

A solution with a high concentration of solute

Hypoosmotic

A solution with a low solute concentration

Ammonia

A carcinogenic nitrogenous waste resulting from the deamination of amino acids in the liver, which is often combined with carbon dioxide to form less-toxic urea

Urea

A nitrogenous waste common in humans and other mammals where ammonia is combined with carbon dioxide to form a less toxic metabolic waste

Uric Acid

A product from the breakdown of nucleic acids, which is excreted through the kidneys

Deamination

The removal of an amine group from an organic compound

Kidney

The primary organ that excretes metabolic waste by producing urine

Urinary Sphincter Muscle

A ring of muscle that is responsible for controlling urine release

Urethra

The duct where urine is released from the body

Renal Artery

The blood vessel which carries blood into the kidneys for ultrafiltration

Renal Vein

The blood vessel which carries filtered blood out of the kidney

Cortex

The outer layer of the kidney composed of connective tissue

Medulla

The “salty” inner layer of the kidney

Renal Pelvis

A hollow chamber which connects the kidney to the ureter

Nephron

The functional unit of the kidney which engages in ultrafiltration and reabsorption processes

Afferent Arteriole

The blood vessel which carries blood into the nephron, and specifically the glomerulus for filtration

Efferent Arteriole

The blood vessel which carries blood out of the glomerulus

Glomerulus

The capillary bed of the nephron where small particles, including urea, glucose, and ions are removed from the bloodstream

Bowman’s Capsule

The cup-like structure where the filtrate from the glomerulus enters

Peritubular Capillary

A blood vessel which wraps around a kidney tubule for the reabsorption of valuable nutrients like ions and sugars from the nephron and the recycling of bicarbonate ions

Aldosterone

A hormone produced by the adrenal cortex that regulates the permeability of distal convoluted tubule and collecting duct to reabsorb ions and water from the nephron into the bloodstream

Proximal Convoluted Tubule

A region of the nephron where nutrients are actively transported into the apical membrane, and then passively transported into the basolateral membrane to reabsorb desirable nutrients that exited the bloodstream at the glomerulus

Threshold Level

The maximum concentration of nutrients that can be reabsorbed into the bloodstream through the reabsorption process in the kidneys

Loop of Henle

A specialized tubule part of the nephron which descends into the medulla before ascending out to maximize water and ion reabsorption into the bloodstream, employing an efficient countercurrent exchange system

Descending Limb

A section of the loop of Henle permeable to water that travels down into the medulla, allowing for water reabsorption

Ascending Limb

A section of the loop of Henle permeable to ions that travels up into the cortex from the medulla, allowing for ion reabsorption

Distal Convoluted Tubule

A region of the nephron where water and salts are reabsorbed into the peritubular capillaries which is regulated by aldosterone

Collecting Duct

The final region of the nephron regulated by ADH and aldosterone where water can be absorbed into the peritubular capillaries before entering the ureter

Buffer

A substance, often in solution, that resists changes to pH, which in the body aids in homeostasis

Antidiuretic Hormone (ADH)

A hormone which is produced by the hypothalamus and secreted by the pituitary gland when osmolarity exceeds 300 mosm/L, which is involved in controlling the permeability of the distal tubule and collecting ducts to water and facilitating thirst

Diuresis

The increased excretion of urine by the body

Hypothalamus

A crucial brain structure responsible for receiving signals from the endocrine system and producing and releasing hormones to maintain homeostasis, like ADH

Adrenal Cortex

A brain structure responsible for producing aldosterone

Renin-Angiotensin-Aldosterone System (RAAS)

The hormonal system which is triggered by low blood pressure or osmolarity which regulates blood pressure and fluid balance in the body

Juxtaglomerular Apparatus

A kidney structure found near the afferent arteriole and glomerulus which detects changes in blood pressure, volume, and ion concentration, releasing renin when low

Renin

An enzyme which when released converts angiotensinogen into angiotensin

Angiotensinogen

The inactive form of angiotensin

Angiotensin

A peptide hormone which causes arteriole constriction and triggers the release of aldosterone

Diabetes Mellitus

A disorder caused by decreased insulin effectiveness which results in high blood sugar levels

Type I DM

A form of diabetes mellitus where the body does not produce enough insulin

Type II DM

A form of diabetes mellitus where there is decreased recognition of insulin by cells

Diabetes Insipidus

A disorder where ADH-producing cells are destroyed, resulting in greater urine output (dilute urine) and thirst

Nephritis

A disease characterized by inflamed nephrons where capillaries within the glomerulus experience damage, allowing for larger particles like red blood cells and proteins to enter the Bowman’s Capsule, resulting in increased urine output

Kidney Stone

A solid, crystalized mass that form in the kidneys from minerals, acids, and salts and can block the ureter

Hemodialysis

A kidney dialysis procedure where blood is extracted from the body and filtered through a dialyzer before being sent back into the body

Peritoneal Dialysis

A kidney dialysis procedure where blood is filtered through the peritoneum with dialysate which enters the body through a catheter

Sessile

Immobile

Motile

Capable of motion

Myogenic Muscle

Muscle that composes the heart, which is also referred to as cardiac muscle, which is striated, multinucleated, and branched

Smooth Muscle

Muscle that composes organs like the stomach, which is non-striated, mononucleated, and is composed to individually independent cells

Skeletal Muscle

Muscle responsible for movement, which is striated and multinucleated, and is composed of linear bundles of fibre

Flexor

A muscle whose contraction bends an appendage

Extensor

A muscle whose contraction extends an appendage

Tendon

A tissue which connects muscle to bones