THE LYMPHATIC SYSTEM

LYMPHATIC SYSTEM

Network of vessels, organs, and tissues

transporting lymph and supporting immunity.

LYMPHATIC SYSTEM

Includes lymph, vessels, nodes, spleen, thymus,

tonsils, and bone marrow.

Maintains fluid balance, defends against infections,

and absorbs dietary fats.

Maintains fluid balance, defends against infections,

and absorbs dietary fats.

Lymph:

Maintains fluid balance, defends against infections,

and absorbs dietary fats.

Lymphatic Vessels:

Transport lymph throughout the

body.

Lymph Nodes:

Filter pathogens; contain immune

cells (B and T lymphocytes).

Spleen:

Filters blood, removes old RBCs, and stores

WBCs.

Thymus:

Matures T lymphocytes.

Tonsils:

Trap pathogens entering via the mouth and

nose.

Bone Marrow:

Produces lymphocytes.

FIRST LINE OF DEFENSE

(Innate Immunity - Non-Specific)

Physical:

Chemical:

Mechanical:

FIRST LINE OF DEFENSE (3)

Physical:

Skin, mucous membranes.

Chemical:

Stomach acid, enzymes, sweat, saliva.

Mechanical:

Tears, cilia in respiratory tract.

SECOND LINE OF DEFENSE

(Innate Immunity - Non-Specific)

Phagocytic Cells:

NK Cells:

Inflammation & Fever.

Complement System.

SECOND LINE OF DEFENSE (4)

Phagocytic Cells:

Macrophages, neutrophils.

NK Cells:

Destroy virus-infected or cancerous

cells.

Lymph

_ forms when plasma leaks from capillaries

into tissues and is collected by lymphatic capillaries.

lymphatic capillaries

Lymph forms when plasma leaks from capillaries

into tissues and is collected by _

Lymph Production & Drainage

It flows through lymphatic vessels, passes through

lymph nodes for filtration, and empties into the

bloodstream.

Lymph Production & Drainage

Lymph forms when plasma leaks from capillaries

into tissues and is collected by lymphatic capillaries.

Lymph Production & Drainage

The right lymphatic duct drains the upper right

body, while the thoracic duct drains the rest.

right lymphatic duct

The _ drains the upper right

body, while the thoracic duct drains the rest.

thoracic duct

The right lymphatic duct drains the upper right

body, while the _ drains the rest.

Plasma

_ leaks from capillaries into tissues, forming

interstitial fluid.

interstitial fluid

Plasma leaks from capillaries into tissues, forming

_.

Interstitial fluid

_ carries nutrients and waste

between blood and cells.

blood and cells

Interstitial fluid carries nutrients and waste

between_ and -.

Lymphatic capillaries

_ absorb the fluid, turning it

into lymph.

lymph

Lymphatic capillaries absorb the fluid, turning it

into _.

Lymph

_ moves through lymphatic vessels, which act

like highways to the heart.

lymphatic vesselslymphatic vessels

Lymph moves through _, which act

like highways to the heart.

heart

Lymph moves through lymphatic vessels, which act

like highways to the -.

Lymph nodes

_ filter out bacteria and viruses to keep

the body safe.

bacteria and viruses

Lymph nodes filter out _ 2 to keep

the body safe.

B and T lymphocytes

Immune cells (_ 2) attack harmful

invaders.

harmful

invaders

Immune cells (B and T lymphocytes) attack _.

bloodstream

Lymph returns to the _ through two

main drainage points.

right head, chest, and arm,

The right lymphatic duct drains lymph from the _ 3 while the thoracic duct

drains the rest.

rest

The right lymphatic duct drains lymph from the

right head, chest, and arm, while the thoracic duct

drains the _.

subclavian veins

Both ducts (right lymphatic duct and the thoracic duct) empty into the _, restoring fluid balance and supporting immunity.

fluid balance; immunity

Both ducts (right lymphatic duct and the thoracic duct) empty into the subclavian veins, restoring - and supporting -.

Antigen:

Antibody:

Binding Mechanisms:

Antigen-Antibody Binding Process

Antigen:

Foreign substance triggering immune

response.

Antibody:

Protein from B cells binding to antigens.

Binding Mechanisms:

Neutralization, Agglutination,

Opsonization, Complement Activation.

Antigen (Ag):

Foreign Substance

Triggering Immune Response

antigen

is a harmful substance like a virus,

bacteria, or toxin.

immune system

The_detects antigens as threats

and reacts to protect the body.

antigens

The immune system detects _ as threats

and reacts to protect the body.

antigens

_ trigger the production of antibodies,

which help fight infections.

Antibody (Ab):

Protein from B Cells

Binding to Antigens

Antibodies

are Y-shaped proteins made by B cells

to fight harmful invaders.

antibody

Each _ fits a specific antigen, like a lock and

key.

antibodies

Once attached, _ neutralize or destroy the

antigen to protect the body.

Skinned Knee:

First Barrier of Protection is Broken

immune cells

An invader enters the body through the cut, where _ have begun to gather to protect the body.

destroy and digest

The immune cells begin to _ 2the invader and its antigens

antigen-presenting cells

Some of the immune cells transform into _ that tell other immune cells about the invader

Antibodies stick to viruses like gum, blocking them

from entering your cells.

Binding Mechanisms - Neutralization

They also stop harmful toxins from bacteria from

causing damage.

Antibodies

_ stick to viruses like gum, blocking them

from entering your cells.

Binding Mechanisms - Neutralization

Antibodies stick to viruses like gum, blocking them

from entering your cells.

Binding Mechanisms - Neutralization

They also stop harmful toxins from bacteria from

causing damage.

Binding Mechanisms - Agglutination

Antibodies act like glue, sticking harmful bacteria

together into clumps so they can’t spread easily.

Binding Mechanisms - Agglutination

These clumps make it easier for white blood cells to

find and remove the bacteria quickly.

Binding Mechanisms - Opsonization

Some bacteria have slippery surfaces, making them

hard to catch.

slippery

Some bacteria have _ surfaces, making them

hard to catch.

Binding Mechanisms - Opsonization

Antibodies coat bacteria, making them easier for

phagocytes to recognize.

Binding Mechanisms - Opsonization

Phagocytes then engulf and destroy the coated

bacteria, preventing infection.

bacteria

Antibodies coat _, making them easier for

phagocytes to recognize.

Phagocytes

_ then engulf and destroy the coated

bacteria, preventing infection.

Binding Mechanisms - Complement

Activation

The complement system is a group of proteins that

enhance immune defense by marking and attacking

pathogens.

pathogens

The complement system is a group of proteins that

enhance immune defense by marking and attacking

_.

Binding Mechanisms - Complement

Activation

It forms the membrane attack complex (MAC),

creating pores in pathogens, leading to cell lysis.

membrane attack complex (MAC)

It forms the_,

creating pores in pathogens, leading to cell lysis.

Binding Mechanisms - Complement

Activation

Complement proteins also aid opsonization

(coating invaders for easier removal) and trigger

inflammation to recruit immune cells.

immune cells

Complement proteins also aid opsonization

(coating invaders for easier removal) and trigger

inflammation to recruit _.

Recognition

Engulfment

Digestion

Exocytosis

Phagocytosis 4

Recognition

The immune cell (phagocyte) identifies and binds to a

foreign invader (e.g., bacteria) using receptors.

Opsonization (coating with antibodies or

complement proteins) enhances recognition.

Opsonization

_ (coating with antibodies or

complement proteins) enhances recognition.

Engulfment

The phagocyte extends its membrane around the

pathogen, enclosing it within a vesicle called a

phagosome.

phagosome

The phagocyte extends its membrane around the

pathogen, enclosing it within a vesicle called a

_.

Digestion

The phagosome fuses with a lysosome, forming a

phagolysosome. Enzymes and toxic molecules break

down the pathogen.

phagolysosome

The phagosome fuses with a lysosome, forming a

_. Enzymes and toxic molecules break

down the pathogen.

Exocytosis

Waste products from digestion are expelled from the

phagocyte, completing the process.

Injury

Histamine Release and Vasodilation

WBC Migration

Pathogen Removal

Inflammation (4)

Injury

Damage to tissues triggers the release of signals

alerting the immune system.

histamine

Mast cells release _, increasing blood flow

and making blood vessels more permeable. After this,

blood vessels widen, allowing more immune cells to

reach the affected area, causing redness and

swelling.

Histamine Release and VasodilationHistamine Release and Vasodilation

Mast cells release histamine, increasing blood flow

and making blood vessels more permeable. After this,

blood vessels widen, allowing more immune cells to

reach the affected area, causing redness and

swelling.

WBC Migration

White blood cells (WBCs), such as neutrophils and

macrophages, move to the site to fight infection.

neutrophils and

macrophages

White blood cells (WBCs), such as _ 2, move to the site to fight infection.

Pathogen Removal

Immune cells destroy the invader through

phagocytosis, and tissue repair begins.

Innate (Non-Specific) Immunity:

Adaptive (Specific) Immunity:

Active Immunity:

Passive Immunity:

Mechanism of Immunity 4

Innate (Non-Specific) Immunity:

Immediate defense,

no memory.

Adaptive (Specific) Immunity:

Long-term, antigen-

specific response.

Adaptive (Specific) Immunity:

Humoral (B cells) & Cell-Mediated (T cells).