Lymphatics

Question 1

what is lymph?

Answer 1

Tissue fluid (interstitial fluid) that enters the lymphatic vessels

Question 1

lympahtic system

Answer 1

essentially a drainage system accessory to venous system

larger particles that escape into tissue fluid can only be REMOVED via lymphatic system

Question 2

functions of lymph system

Answer 2

Reabsorbs excess interstitial fluid:
returns it to the venous circulation
maintain blood volume levels
prevent interstitial fluid levels from rising out of control.

Transport dietary lipids:
transported through lacteals
drain into larger lymphatic vessels
eventually into the bloodstream.

lymphocyte development, and the immune response

Question 3

components of lump system

Answer 3

1. Lymph
2. Lymphatic Vessels

Lymphatic Capillaries
Lymphatic Vessels
Lymphatic Trunks
Lymphatic Ducts

3. Lymphatic Organs
   Thymus
   Lymph Nodes
   Spleen
   Tonsils
4. Lymphatic cells

Question 4

lymph vessels

Answer 4

Lymphatic capillaries –
Lymphatic collecting vessels
Lymphatic trunks –
Lymphatic ducts –

Question 5

lymphatic capillaries

Answer 5

interstitial fluid
endothelial flaps
tissue cell
lymph vessel endothelial cells
lymph interstitial fluid

SLIDE 67

Features of structure:

Blind end

Single layer of overlapping endothelial cells
More permeable than that of blood capillary

Absent from avascular structures, brain, spinal cord splenic pulp and bone marrow

Question 6

Lamph capillaries - Lactals

Answer 6

The small intestine contains special types of lymphatic capillaries called lacteals.

Lacteals pick up not only interstitial fluid, but also dietary lipids and lipid-soluble vitamins.

The lymph of this area has a milky color due to the lipid and is also called chyle. (kail)

Question 7

Lymphatic vessels - feature of structures

Answer 7

Features of structure
Three layered wall but thinner than vein,
More numerous valves than in vein
Interposed by lymph nodes at intervals
Arranged in superficial and deep sets

Question 8

lymph trunks

Answer 8

Right and left jugular trunk

Right and left subclavian trunks

Right and left mediastinal trunks

Right and left lumbar trunks

Intestinal trunk

Question 9

right lymphatic duct

Answer 9

Formed by union of right jugular, subclavian, and bronchomediastinal trunks

Ends by entering the right venous angle

Question 10

Thoracic duct

Answer 10

Begins in front of L1 as a dilated sac, the cisterna chyli,

formed by left and right lumbar trunks and intestinal trunk

Enter thoracic cavity & ascends

Travels upward, veering to the left at the level of T5

At the root of the neck, it turns laterally

arches forwards and descends to enter the left venous angle

before termination, it receives the left jugular, Subclavian and broncho-mediastinal trunk

Question 11

lymphatic cells

Answer 11

Also called lymphoid cells.

Located in both the lymphatic system and the cardiovascular system.

Work together to elicit an immune response.

Types of lymphatic cells are:
macrophages
epithelial cells
dendritic cells
lymphocytes

Question 12

drainage pattern (ducts

Answer 12

RIGHT LYMPHATIC DUCT -Receives lymph from right half of head, neck, thorax and right upper limb, right lung, right side of heart, right surface of liver

THORACIC DUCT - Drains lymph from lower limbs, pelvic cavity, abdominal cavity, left side of thorax, and left side of the head, neck and left upper limb

Question 13

lymphatic organs –> primary and secondary

Answer 13

Primary organs
Red bone marrow
Thymus gland

Secondary organs
Lymph nodes
Lymph nodules
Spleen

Question 14

lymph nodes

Answer 14

Nodes:
Thoracic cavity nodes
cervical
axillary
supratrochlear
abdominal
pelvic
inguinal

Small, round or oval

located along the pathways of lymph vessels.
length from 1 - 25 millimeters

Typically found in clusters
receive lymph from many body regions.

Lymph nodes are also found individually throughout the body tissues.

Question 15

structure of lymph node

Answer 15

Bean-shaped bodies

With afferent vessels (entering at the periphery) and efferent lymph vessels(emerging at the hilus)

Arranged in groups, along the blood vessels or the flexural side of the joint

Divided into superficial and deep groups

Question 16

spleen

Answer 16

Left epigastric region
between 9th-11th rib
in line of 10th rib

Largest lympahtic organ in the body

can vary considerably in size and wieght

Question 17

thymus

Answer 17

Consists of two elongated lobes

Is a large organ in the fetus

Occupies the thoracic cavity behind the sternum

Secrete lymphopoietin

Question 18

lymphatic nodules

Answer 18

Oval clusters of lymphatic cells with some extracellular matrix that are not surrounded by a connective tissue capsule.

Filter and attack antigens.

In some areas of the body, many lymphatic nodules group together to form larger structures.

mucosa-associated lymphatic tissue (MALT) or tonsils

very prominent in the mucosa of the small intestine, primarily in the ileum
Peyer patches

also present in the appendix

Question 19

MALT

Answer 19

mucosa-associated lymphatic tussie:

Peyers patches, tonsils, and the appendix 9digestive tract)

• lymphoid nodules in the walls of the bronchi (respiratory tract

MALT protects the digestive and respiratory systems from foreign matter

Question 21

Tonsils

Answer 21

clusters of lymphatic cells and extracellular matrix not completely surrounded by a connective tissue capsule.

Consist of multiple germinal centers and crypts

Several groups of tonsils form a protective ring around the pharynx.
pharyngeal tonsils (or adenoids) in nasopharynx
palatine tonsils in oral cavity
lingual tonsils along posterior one-third of the tongue

Question 22

Lymphangitis

Answer 22

Inflammation of the lymph vessels

Commonest cause bacteria called streptococcus pyogenes(most common).

Lymph vessels appear as red streaks through the skin

Question 23

filariasis

Answer 23

larvae mature into adult worms and spread through the lymphatic vessels, where they mate and lay eggs

Microfilaria develop into infective larvae in the mosquito and are injected into a new host

Question 24

Lymphedema

Answer 24

Occurs due to accumulation of lymphatic fluid in the interstitial tissue

Sometimes can be appreciated after wearing tight clothing or jewellary on affected limb

Question 25

lymphadenopathy

Answer 25

Means a disease of the lymph nodes

Lymph nodes become swollen/ enlarged and may be painful to touch

Question 26

lymphomas

Answer 26

Cancers originating either from the lymphocytes in the lymph nodes or the lymphatic tissue in organs

Risk factors – HIV, HEPATITIS, EBV infections

Question 27

tonsillitis

Answer 27

Infection of the pharyngeal tonsils

Tonsils are swollen,

Fever and pain during swallowing usually present
Treatment – surgical removal of tonsils
(TONSILLECTOMY)

Question 28

splenomegaly

Answer 28

enlarged spleen
various causes

Question 29

capillary anatomy of lymphs