Chapter 20:The Lymphatic System

Florence Rena Saba – 1871-1953 - discovered important link between blood

vessel and lymphatic vessel genesis

Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn

Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.

Figure 20.1: Distribution and special structural features of lymphatic capillaries, p. 774.

Venoussystem

Arterialsystem

Heart

Lymph ductLymph trunkLymph node

Lymphaticsystem

Lymphaticcollecting

vessels,with

valves

Lymphaticcapillary

Bloodcapillaries

Tissue cell Bloodcapillaries

Tissue fluid

Venule Arteriole

Lymphatic capillary

Loose connective tissue around capillaries

Fibroblast in looseconnective tissue

Flaplike minivalve

Endothelialcell

Filamentsanchored toconnectivetissue

(a)

(b)

Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn

Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.

Figure 20.2a: The lymphatic system, p. 776.

Cervicalnodes

Entrance ofright lymphaticduct into rightsubclavian vein

Internaljugular veinEntrance of thoracicduct into leftsubclavian veinThoracic duct

Cisterna chyliLymphaticcollectingvessels

Axillarynodes

Inguinalnodes

Regionallymph nodes:

Aorta

(a)

Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn

Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.

Figure 20.4: Lymph node, p. 778.

(b)(a)

Follicles

Trabecula

Subcapsularsinus

Capsule

MedullarycordsMedullarysinuses

Afferentlymphaticvessels

Efferentlymphaticvessels

Capsule

Trabeculae

Hilum

Cortex:• Lymphoid follicle• Germinal center• Subcapsular sinus

Medulla:• Medullary cord• Medullary sinus

Human Anatomy and Physiology, 7eby Elaine Marieb & Katja Hoehn

Copyright © 2007 Pearson Education, Inc.,publishing as Benjamin Cummings.

Figure 20.5: Lymphoid organs, p. 779.

Tonsils (inpharyngealregion)

Thymus (inthorax; mostactive duringyouth)

Spleen (curvesaround left sideof stomach)

Peyer’s patches(in intestine)Appendix