A&PII: Lab 3: The Lymphatic System

Question 1

Lymph

Answer 1

clear, yellowish liquid flowing in a 1-way direction toward the heart

Question 2

Lymphatic vessels

Answer 2

lymph is transported by a system of these tubular vessels in a direction leading toward the heart

Question 3

Primary lymphatic organs

Answer 3

organs containing stem cells that produce lymphocytes and serve as the site for their preparation to recognize unwanted substances and mount an immune response

Question 4

Thymus

Answer 4

a primary lymphatic organ; soft, superior to the heart (larger in children, shrinks with age)

Question 5

Red bone marrow

Answer 5

a primary lymphatic organ inside bones

Question 6

Secondary lymphatic organs

Answer 6

contain WBC’s that are immunocompetent (ready to defend against unwanted substances

Question 7

Lymph nodes

Answer 7

secondary lymphatic organs; small, pea-sized organs distributed along the lymphatic vessels in various regions of the body

Question 8

Spleen

Answer 8

secondary lymphatic organ; soft organ located lateral to the stomach in the abdominal cavity

Question 9

Lymphatic nodules

Answer 9

secondary lymphatic organs; clusters of lymphatic tissue that form aggregations throughout the body

Question 10

Mucosa-associated lymphoid tissue (MALT)

Answer 10

one of the larger lymphatic nodules, found in the mucous membranes of the GI, respiratory, urinary, and reproductive tracts

Question 11

Peyer’s patches

Answer 11

one of the larger lymphatic nodules; aggregated lymphatic follicles in the wall of the small intestine

Question 12

Bronchial nodules

Answer 12

one of the larger lymphatic nodules; in the walls of the bronchi

Question 13

Tonsils

Answer 13

one of the larger lymphatic nodules; found in the mouth and throat

Question 14

Pharyngeal tonsil

Answer 14

tonsil in the posterior wall of the nasopharynx

Question 15

Palatine tonsils

Answer 15

paired tonsils in the posterior oral cavity wall

Question 16

Lingual tonsils

Answer 16

paired tonsils at the root of the tongue

Question 17

Lymphatic capillaries

Answer 17

lymph originates when interstitial fluid finds its way into these microscopic, blind-ended structures

Question 18

Lymphatic vessels

Answer 18

from the capillaries, lymph flows into these structures

Question 19

Lymph nodes

Answer 19

as lymph flows in a direction toward the heart, it passes through numerous of these structures, which are stationed in regional locations within the lymphatic vessel pathway; filters lymph of unwanted materials due to the WBC’s residing within them

Question 20

Lymphatic ducts

Answer 20

the lymphatic vessels channel lymph into these larger vessels, which eventually merge with the subclavian veins near the heart

Question 21

Thoracic duct

Answer 21

one of 2 major ducts; drains most of the body into the left subclavian vein

Question 22

Right lymphatic duct

Answer 22

shorter of 2 major ducts; drains into the right subclavian vein

Question 23

Cysterna chyli

Answer 23

the thoracic duct receives lymph from a convergence of abdominal lymphatic vessels forming this expanded sac

Question 24

Capsule

Answer 24

each lymph node consists of this outer fibrous connective tissue that includes trabeculae

Question 25

Trabeculae

Answer 25

internal extensions of the capsule of a lymph node, forming a network of tiny compartments

Question 26

Reticular tissue

Answer 26

connective tissue occupying the compartments of trabeculae within a capsule of a lymph node; contains protein fibers that support reticulocytes

Question 27

Reticulocytes

Answer 27

specialized fibroblasts supported by reticular tissue; their function is to support developing lymphocytes

Question 28

Cortex

Answer 28

outer section of the interior of a lymph node

Question 29

Medulla

Answer 29

inner section of the interior of a lymph node

Question 30

Lymphatic nodules

Answer 30

the cortex and medulla of a lymph node contain these, which contain large numbers of WBC's (mainly lymphocytes and macrophages); usually ovoid in the cortex and narrow in the medulla

Question 31

Medullary cords

Answer 31

lymphatic nodules that are narrow in the medulla

Question 32

Germinal center

Answer 32

the center of each lymphatic nodule consists of this, which contains dividing lymphocytes

Question 33

Afferent vessels

Answer 33

lymph enters a node by way of these structures, which unite with the lymph node at its capsule

Question 34

Subcapsular sinus

Answer 34

once inside a node, lymph passes through this cavity, then enters the spaces between trabeculae

Question 35

Trabecular sinuses

Answer 35

cavities filled with reticular tissue and WBC's

Question 36

Medullary sinuses

Answer 36

cavities into which lymph drains before exiting a lymph node

Question 37

Efferent vessels

Answer 37

lymph exits a node by way of 1 or 2 of these structures

Question 38

Hilus (lymph node)

Answer 38

the efferent vessels exit from this slight depression in a lymph node

Question 39

Splenic artery

Answer 39

the spleen receives a large supply of blood by way of this artery

Question 40

Splenic vein

Answer 40

the spleen is drained by this vein

Question 41

Hilus (spleen)

Answer 41

the splenic artery and vein merge with the spleen at a depression known as this

Question 42

Efferent lymphatic vessels

Answer 42

carry lymph away from the spleen

Question 43

White pulp

Answer 43

part of the spleen characterized by an abundance of WBC's (mainly lymphocytes); appears dark purple under the microscope (due to nucleated cells --> nucleic acids)

Question 44

Red pulp

Answer 44

part of the spleen characterized by the abundance of RBC's, due to its function of RBC storage; due to a lack of nuclei, this appears relatively light under the microscope

Question 45

Thymic lobes

Answer 45

the external capsule of the thymus extends inward to divide it internally into these 2 sections

Question 46

Lobules

Answer 46

each thymic lobe divides further into these numerous structures, each of which consists of an outer cortex and an inner medulla

Question 47

T cells

Answer 47

1 of 2 classes of lymphocytes; differentiate within the cortex of the thymus

Question 48

B cells

Answer 48

1 of 2 classes of lymphocytes; differentiate within red bone marrow

Question 49

Hassall's corpuscles

Answer 49

the medulla of the thymus contains these distinctive structures, each of which consists of a circular arrangement of reticular cells