LYMPHATIC SYSTEM

Fluid Balance, Fat Absorption, Defense

3 Functions of Lymphatic System

Fluid Balance

Transports fluids from the tissues
back to the blood

Three

How many liters of fluid escapes

Edema

impairs cells exchange of
nutrients, gases, and waste with
interstitial fluid and blood

Fat Absorption

It absorbs lipids and other
substances from the digestive
system

Lipids

pass through the lymphatic
vessels in the lining of the small
intestine

lacteals

the lining of the small
intestine

Lacteals and Venus Circulation

In which Lipids pass through the lymphatic
vessels

Chyle

The lymph here appears white
because of its lipid content

pathogen

any substance that
cause disease or damage to tissues
of the body

lymph nodes

Where Pathogens are filtered from the
lymph

spleen

Pathogens are filtered in the blood by

Lymph

Fluid that enters lymphatic
capillaries composed of water and
some solutes

substances in plasma and substances derived from cells

Lymph solutes are derived from two
sources

ions, nutrients, gases, some proteins

examples of substances in plasma

hormones, enzymes and waste
products

examples of substances from cells

Lymphocytes

Type of WBC involved in defense

Lymphatic Vessels

Are found in different areas of the
body and carry the lymph fluid

COMPONENTS OF THE LYMPHATIC SYSTEM

Lymph, Lymphocytes, Lymphatic vessels, Lymph nodes, Tonsils, Spleen, Thymus gland

LYMPHATIC CAPILLARIES AND VESSELS

Carries fluid in one direction from tissues
to circulatory system

LYMPHATIC CAPILLARIES AND VESSELS

Fluid moves from blood capillaries into tissue spaces

LYMPHATIC CAPILLARIES

tiny, closed-ended vessels made of simple
squamous epithelium

False

In lymphatic capillaries, fluid moves easily into because they are semi-permeable since they have basement membrane

valves

the overlapping of the squamous cells act as ___ that prevent the backflow of the lymph fluid

CNS, Bone marrow, epidermis, and cartilage

lymphatic capillaries are present in most tissues except

LYMPHATIC VESSELS

resemble small veins

LYMPHATIC VESSELS

where lymphatic capillaries join

False

Lymphatic vessels are two-way valves

right lymphatic duct and thoracic duct

Lymphatic vessels join and eventually
empty into the blood at two locations

RIGHT LYMPHATIC DUCT

where lymphatic vessels from right upper
limb and right head, neck, chest empty

RIGHT LYMPHATIC DUCT

empties into right subclavian vein

THORACIC DUCT

rest of body empties from lymphatic vessels

THORACIC DUCT

empties into left subclavian vein

TONSILS

form a protective ring of lymphatic tissue
around nasal and oral cavities

TONSILS

protect against pathogens entering the
mouth and nose

Pharyngeal tonsil, Palatine tonsil, Lingual Tonsil

3 types of Tonsils

Palatine Tonsils

on each side of oral cavity

Palatine Tonsils

usually referred to as the tonsils

adenoidectomy

removal of Palatine Tonsils

Pharyngeal Tonsils

near internal opening of nasal cavity

Pharyngeal Tonsils

called adenoid when enlarged

tonsillectomy

Removal of Pharyngeal Tonsils

Lingual Tonsils

posterior surface of tongue

False

Lingual Tonsils are infected more often and easy to remove

LYMPH NODES

rounded structures that vary in size

True

lymph passes through at least one lymph
node before entering blood

groin, armpit, neck

Where lymph nodes are found

2 functions of Lymph Nodes

1. Activate the immune system
2. Remove pathogens from the lymph through macrophages

SPLEEN

size of clenched fist

True

Spleen is located in left superior portion of the
abdominal cavity

False

Spleen does not filter blood

SPLEEN

detect and respond to foreign substances

lymphocytes and macrophages

2 types of foreign substances in which spleen detects and responds to

SPLEEN

blood reservoir

Smooth Muscle in Splenic blood vessels

During emergency situations the_____ in the splenic blood vessels can contract to move a small
amount of blood from the spleen into the circulation.

Splenectomy

removal of spleen

False

After removal the function of the spleen will not be compensated by other lymphatic organs and the liver

White pulp

lymphatic tissue surrounding arteries

Red pulp

contains macrophages and red blood cells that connect to veins

THYMUS GLAND

bilobed gland

True

Thymus gland is located in superior mediastinum

True

Thymus gland is also a site of production of large number of T cells in which most deteriorate

Cortex

dark-staining areas containing
numerous lymphocytes

Medulla

lighter-staining areas with few lymphocytes

IMMUNITY

ability to resist damage from pathogens

Microbes, toxins, cancer cells

examples of immunity

Types of immunity

Innate or nonspecific

Types of immunity

Adaptive or specific

INNATE IMMUNITY

present at birth

physical barriers, chemical mediators,
cells, inflammatory response

what are the defense against any pathogen accomplished

PHYSICAL BARRIERS

First line of defense

Skin and mucous membranes

act as physical barriers

Tears, saliva, urine

wash away pathogens

CHEMICAL MEDIATORS

chemicals that can kill microbes and
prevent their entry into cells

Lysosome

found in tears and saliva to kill
bacteria

Mucus

Mucous membranes prevent entry
of microbes

Complement

group of more than 20 plasma
proteins

False

Complement circulates in active form

Complement

activated when it binds with a
foreign substance

Complement

promotes inflammation,
phagocytosis and cell lysis

Histamine

promote inflammation by causing
vasodilation

Interferons

proteins that protect against viral
infections by stimulating
neighboring cells to produce
antiviral proteins

White blood cells

produce in red bone marrow and
lymphatic tissue that fight foreign
substances

chemotaxis

movement of WBCs
in response to a chemical stimulus

White blood cells

complement, leukotrienes, kinins,
histamine

Phagocytic cells

ingest and destroy foreign substances

neutrophils and macrophages

Examples of Phagocytic cells

Neutrophils

first cells to respond to infection but
die quickly

Pus

accumulation of fluid, dead
neutrophils and other cells at the site
of inflammation

Macrophages

monocytes that leave blood and enter tissues

False

macrophages are responsible for phagocytic activity in the early stages of infection

Macrophages

given specific names for certain areas of body

Kupffer cells in liver, dust cells in the lungs, microglia in CNS

Examples of Macrophages

Basophils, Mast cells, Eosinophils, Nature Killer Cells

CELLS OF INFLAMMATION

Basophils

motile cells that leave blood and enter infected tissues

Basophils and Mast Cells

derived from red bone marrow

Mast cells

non-motile cells found in skin,
lungs, gastrointestinal tract,
urogenital tract

Eosinophils

produced in red bone marrow

Eosinophils

associated with allergies and asthma

Natural Killer Cells

type of lymphocyte produced in red
bone marrow