Chapter 21 The Lymphoid and Immune system

Comprehensive flashcards covering the lymphoid and immune systems, including anatomical structures, lines of defense, innate and adaptive immunity, and specific cellular mechanisms.

The __________ system is not an organ system, but a cell population that inhabits all organs and defends the body from agents of disease.

immune

Blood capillaries reabsorb $85\%$ of filtered fluid, while the remaining __________ enters the lymphatic vessels.

$$15\%$$

Specialized lymphatic vessels in the small intestine called __________ absorb dietary lipids that are not absorbed by blood capillaries.

lacteals

The __________ duct receives lymph from the right arm, right side of the head, and thorax, then empties into the right subclavian vein.

right lymphatic

The thoracic duct begins as a sac in the abdomen called the __________.

cisterna chyli

Primary lymphoid organs, where T and B cells become immunocompetent, include red bone marrow and the __________.

thymus

Secondary lymphoid organs include lymph nodes, tonsils, and the __________.

spleen

Lymph nodes located in the armpit are called __________ lymph nodes.

axillary

The __________ is the body's largest lymphoid organ and cleanses the blood of aged blood cells and platelets.

spleen

__________ immunity consists of defenses we are born with, has a local effect, and lacks memory.

Innate

The __________ line of defense consists of the skin and mucous membranes.

first

The skin's __________ is a thin film of lactic and fatty acids from sweat and sebum that inhibits bacterial growth.

acid mantle

Mucous membranes contain __________, an enzyme that destroys bacterial cell walls.

lysozyme

__________ are leukocytes that specifically guard against parasites like tapeworms and roundworms.

Eosinophils

Natural killer (NK) cells release proteins called __________ to create a hole in the target cell's plasma membrane.

perforins

Proteins secreted by virally infected cells to serve as an "alarm" to nearby cells are called __________.

interferons

The __________ system is a group of $30$ or more proteins synthesized mainly by the liver that contribute to inflammation, cytolysis, and phagocytosis.

complement

An abnormal elevation of body temperature is known as pyrexia or __________.

fever

The four cardinal signs of inflammation are redness, swelling, __________, and pain.

heat

The movement of neutrophils squeezing through the blood vessel wall during inflammation is called __________.

diapedesis

__________ immunity is mediated by B lymphocytes that produce antibodies to tag extracellular targets for destruction.

Humoral

In the thymus, __________ selection ensures that T cells do not react to self antigens, a process called self tolerance.

negative

Antigen-presenting cells (APCs) include macrophages, B cells, and __________ cells.

dendritic

Antigen-presenting cells display fragments of antigens in the grooves of __________ proteins.

MHC

The four classes of T-cells used in cellular immunity are Cytotoxic T cells, Helper T cells, Memory T cells, and __________ T cells.

Regulatory

Cytotoxic T cells deliver a lethal hit by releasing perforins and __________, which induce apoptosis.

granzymes

In humoral immunity, activated B cell clones differentiate into __________ cells, which secrete antibodies at a rate of $2,000$ molecules per second.

plasma

Antibodies can eliminate antigens through __________, which involves the clumping of enemy cells to immobilize them.

agglutination

In a __________ response to an antigen, antibody levels rise sharply and peak within days because of memory B cells.

secondary