Lymphatic & Respiratory System

The basic structure of the distal end of a single lobule.

multiple alveoli open off a single alveolar duct Network of capillaries, supported by elastic fibers, surrounds each alveolus. Many capillaries maximum gas exchange!

Glottis

narrow opening in larynx that contains vocal cords sounds vibrate like guitar strings. (show vocal cords in action)

T-cells: Cell-mediated immunity

1. Helper T cells (TH): :"Commanders" -Release chemical signals, "cytokines", that costimulate Cytotoxic T cells and B cells to produce thousands of clones that recognize the specific antigen. -stimulate clonal expansion of Cytotoxic T cells and B cells. 2. Cytotoxic T cells (TC): "toxic to cells" -Attack infected cells, foreign cells or cancer cells. -Use direct contact 3. Memory T cells: remain in tissues awaiting reappearance of the antigen. 4. Suppressor T cells: -Inhibit T and B cells

Inflammation

non-specific local, internal response to injury or localized infection. Types of injury that cause inflammation: -infection by pathogens -burns - irritating chemicals -physical trauma.

Whisper

not vibrating vocal cords-can't change pitch. Male Puberty = longer, thicker vocal folds---> result in Adam's Apple? slower vibration = deeper voice

Capillary Pressure differences:

1. Hydrostatic (blood) Pressure -MOVEMENT OF FLUID OUT OF CAPILLARY, -"PUSHING OUT" 2. Osmotic Pressure -MOVEMENT OF WATER INTO CAPILLARY -"PULLING IN" -(water moves toward area of higher solute concentration).

Immediate Allergic Response

occurs within seconds of contact with allergen. 1. B cells produce IgE antibodies 2. IgE antibodies bind to mast cells (tissues) and basophils (blood) 3. Following next exposure to allergen, histamine is released by mast cells and basophils.

Nasopharynx

only air connects nasal cavity to oropharynx pharyngeal tonsil (adenoid) entrance to auditory tube ciliated columnar epithelia

The Tonsils

"First Responders against pathogens" •Lymph nodes cleanse the lymph. •Spleen cleanses the blood. -Lymph nodes are places to: "Meet, greet and destroy pathogens, cancer cells, toxins and debris" --All lymph passes through at least one lymph node!

Immune System OVER-REACTS

"Hypersensitivity" -Allergies -Autoimmune diseases

Immune System UNDER-REACTS

"Immunodeficiency" -SCID" bubble boy disease" -AIDS

Cyclosporin

"anti-rejection treatment" works by blocking the action of Helper T cells and in this way it prevents rejection of donated organs.

Alveolar sac

"bunch of grapes" Alveoli= "single grape" "Dorm suite": Alveolar duct: hallway Alveolar Sac: common area Alveoli: separate dorm rooms Alveolar ducts end at alveolar sacs ("common area") connect to multiple individual alveoli ("dorm rooms") Each lung contains about 150 million alveoli Give lung spongy, airy appearance Vastly increase surface area Total surface area of both lungs together is ~140 m2 (half tennis court) Allow for extensive, rapid gas diffusion to meet metabolic needs

Dendritic Cell

"sentinel" travel long distances to present the antigen to many T and B cells. Most important APC's! (Langerhans cells of skin, in mucus membranes)

Anatomy of the Lungs:

"sponge-like" compress like a sponge and then expand to release the air. (many elastic fibers and air-filled passageways and alveoli)

Pharynx

"throat" , skeletal muscle tube from internal nares to entrance of larynx and esophagus Passageway for air, liquid and food Contains MALT Skeletal muscles aid swallowing

Epiglottis

(elastic cartilage) acts as a switching mechanism to divert food to esophagus(Swallow... feel it go up and down.)can't talk while swallowing!

MALT

(mucosa associated lymphoid tissues) Lymphoid tissue located in mucous membranes throughout body.(line body cavities that are open to the exterior) -Protects at points where pathogens most easily gain entry from the external environment. •Respiratory tract -tonsils •Digestive tract -Peyer's patches (in lining of intestine) •appendix (junction of small and large intestine •Genitourinary tract

The B Cell Response to Antigen Exposure:

--B cells do not require APC! B cells bind to Antigen directly. --B cells still require costimulation by Helper T cells in order to multiply and produce plasma cells and memory B cells

Pressure and Airflow into Lungs

-Air moves down pressure gradient -Hi P Low P -The air pressure in the lungs must be lower than atmospheric pressure for air to flow into lungs. -INHALE: P inside lungs < P outside lungs Increase in lung volume decreases lung pressure. -EXHALE: P inside lungs > P outside Decrease in lung volume increases lung pressure.

Lymph contains

-Excess interstitial fluid that has leaked out of the blood capillaries into the interstitial space. -Plasma proteins that have leaked out of the blood capillaries into the interstitial space. -Dietary fats and fat-soluble vitamins absorbed from the small intestine -Invading organisms (bacteria, viruses, worms) -Lymphocytes

Factors that reduce lung compliance:

-Fibrosis (formation of non-elastic scar tissue) Chronic inflammation (tuberculosis, pneumonia, smoking) -Pulmonary edema (congestive heart failure) -Lack of surfactant in a premature infant (<30 weeks)

SPLEEN

-LARGEST LYMPHOID ORGAN (located on left side of body behind the stomach) 1. Purifies the blood by removing pathogens, cell debris, old red blood cells and old platelets. 2. Stores : -rbc's, platelets and iron (red pulp) -lymphocytes(white pulp) Infections can cause the spleen to enlarge: •mononucleosis •leukemia •A strong blow to the abdomen can rupture the spleen causing severe internal bleeding so that the spleen may have to be removed (more vulnerable to infections)

Fever

-Macrophages release chemicals called pyrogens in response to an infection that stimulate fever. Pyrogens increase the body temperature thermostat in the brain. That is why you feel cold when you have a fever. Increased body temperature: 1. Signals phagocytes to travel to infection site 2. Stimulates phagocytosis to destroy pathogens 3. Slows bacterial growth 4. Stimulates tissue repair

Cystic fibrosis

-Most common lethal inherited disease among -Caucasians of Northern European descent -1/2500 births -Abnormally thick and sticky mucus -Accumulates restricting airflow and possible blocking smaller passageways -Pathogens may colonize the stagnant mucus

Lymphatics

-Network of lymphatic vessels -Contains lymphocytes surrounded by lymph (fluid similar to interstitial fluid) -Includes lymphoid organs and tissues >Contain large numbers of lymphocytes >Connected to lymphatic vessels

Our immune system is able to

1. Identify the invader as foreign 2. Alert the immune system via chemical signals 3. Contain the invader to prevent spreading. 4. Mobilize an army of wbc that attack and destroy the invader before they destroy your tissues. 5. Remember the invader

David Vetter "bubble boy" SCID: Severe Combined ImmunoDeficiency

-Rare Inherited disease -50 affected children worldwide -Born with defective Helper T cells David lived for 12 years in a germ-free bubble David died when a bone marrow transplant from his sister failed because it was infected with Epstein Barr virus and since he lacked a functioning immune system the virus killed him.

2. Compliance

-ability of lungs to stretch and expand Higher Compliance = Easier Expansion /Gas Flow Higher Stretchability of Elastic Fibers

Lymphatic vessels

-carry lymph towards the heart and release the lymph into cardiovascular veins that enter the right atrium of the heart. -lymphatic capillaries-->large lymphatic vessels-->Lymphatic duct-->Subclavian veins-->Right Atrium of the heart -The thoracic duct empties into the left subclavian vein. The right lymphatic duct drains into the right subclavian vein. -The thoracic duct carries lymph originating in tissues inferior to the diaphragm and from the left side of the upper body. The right lymphatic duct drains the right half of the body superior to the diaphragm.

Lymph nodes

-found along the lymphatic vessels -common in the neck, armpit and groin regions -Lymph nodes swell when fighting an infection! "swollen glands" are swollen lymph nodes. -Doctors remove the lymph node if they contain cancer cells to prevent the cancer cells from spreading into the lymphatic vessels.

Lymphocytes

-primary cells of lymphatic system -produced in the red bone marrow -Stored in the lymphoid organs Respond to: -Invading pathogens >bacteria or viruses -Abnormal body cells >Virus-infected cells or cancer cells -Foreign proteins >Toxins produced by bacteria

Cilia

-projections on the surface of cells that form a barrier to foreign invaders. -Electron micrograph of the lining of the windpipe, ciliated cells are interspersed with mucus-producing cells -The mucus helps to trap foreign invaders, and the cilia help move them out of the respiratory tract into the throat by sneezing, coughing or swallowing.

Clonal expansion

-replication of many identical cells, "clones" that recognize a specific antigen. In this way the body produces an "army" of thousands of identical, immune cells that: 1. recognize a specific antigen and mount an attack. 2. produces memory cells that "remember" the antigen for future .

Battleground

-your entire body Enemy: pathogens, cancer cells, transplanted cells, toxins, dead cells debris Army: white blood cells Forts: red bone marrow (produce and store white blood cells) Highways: lymphatic vessels and blood vessels

Each lung...

... is divided into lobes: Right lung: 3 lobes Left lung: 2 lobes Cardiac Notch: heart makes left lung 10% smaller than right lung

Cytotoxic T cells

...bind to a foreign cell and destroy it with toxic chemicals -Perforins and Granzymes directly kill infected cells. -Released Pathogens are destroyed by: granulysins and macrophages Tissue rejection occurs when cytotoxic T cells attack a transplanted cell.

Oxygen Transport: --->

02 INHALED -->Alveolus-->Pulmonary Capillary-->Systemic Capillary-->Tissue Cells

B-cells: Antibody-mediated immunity

1. B cells: when costimulated by Helper T cells cells, form plasma cells which produce a specific type of antibody. 2. Memory B cells: remain in tissues awaiting reappearance of the antigen.

Lymphatic System Functions

1. Drain excess interstitial fluid and return it to the veins that empty into the right atrium. "drainage system" 2. Transport dietary lipid 3. Carry out our Immune responses

Causes of Autoimmune Disorders

1. Genetic factors (inherited) 2. Environmental factors: after infection with a virus or bacteria, the person's antibodies and immune cells cross-react by mistake with their own tissues.

Similarities between lymphatic vessels and cardiovascular veins

1. Lymphatic vessels carry lymph TOWARD the heart like veins. 2. Lymphatic vessels have thin walls like veins. 3. Lymphatic vessels have valves like veins 4. movement of lymph is helped by skeletal muscle contraction and breathing like veins.

Two ways to get active immunity:

1. Natural exposure to the live pathogen. 2. Artificial exposure to a dead or weakened pathogen in a vaccine.

Respiration 3 steps:

1. Pulmonary Ventilation/Breathing Inhalation and exhalation Movement of gases between atmosphere and lungs (alveoli) 2. External (pulmonary) Respiration Gas exchange between alveoli and pulmonary capillaries 3. Internal (tissue) Respiration Gas exchange between systemic tissue cells and systemic capillaries. Supplies oxygen for cellular respiration that occurs in mitochondria to make ATP.

Properties of Adaptive Immunity

1. Specificity Receptors on plasma membrane of each T cell and B cell only bind one specific antigen 2. ​Versatility Millions of different lymphocytes, each recognize a different antigen. 3. Memory Memory cells "remember" antigens for future attacks. 4. Tolerance Ignoring normal "self" tissues

Paralysis/loss of cilia that sweep mucus out of lungs --> chronic bronchitis

Chronic inflammation with neutrophils that destroy elastic fibers: collapse airways--> reduce gas exchange

immediate hypersensitivity (type 1)

Circulating allergen affects mast cells throughout body Rapid changes in capillary permeability produce swelling and edema Raised welts, or hives, appear on skin Smooth muscles in airways contract Can produce drop in blood pressure leading to circulatory failure, anaphylactic shock Treated with antihistamines and epinephrine. (epinephrine dilates airways and constricts blood vessels)

Expiratory reserve volume (ERV)

Maximum amount of air can breath out after tidal volume exhalation

Inspiratory reserve volume (IRV)

Maximum amount of air that can breathe in after tidal volume inhalation.

Diffusion

Movement of ions or molecules from area of high concentration to area of low concentration

autoimmune diseases

Multiple Sclerosis Grave's Disease Type I Diabetes SLE (Lupus)(CT) Rheumatoid Arthritis Addisons disease Treatment: large scale immunosuppression: glucocorticoids

Anoxia

No oxygen Cells die off quickly Damage from strokes or heart attacks are a result of anoxia

Respiratory rate

Number of breaths per minute Normal adult rate 12-18 breaths per minute

White blood cells patrol the body by...

moving out of the blood capillary into the surrounding tissue space and lymph. = diapedesis

Total Lung Capacity

max air lungs can hold TLC = VC + RV

Spirometry

measures respiratory volumes and capacities in a medical setting

Phagocytes Patrol the Body :(neutrophils and macrophages)

1.Move on their own to the site of infection by squeezing through blood and lymph capillaries "diapedesis" 2. Engulf foreign invaders and debris by phagocytosis 3. Release "chemical signals" called "cytokines" to attract other wbc to site of infection "chemotaxis" 4. Distributed throughout the body especially in the blood, lymph and lymphatic organs.

Five Functions of the Respiratory System

1.Moves air along respiratory passageways to and from gas-exchange surfaces of the lungs. 2.Provides large surface area for gas exchange between air and blood capillaries. 3.Protects respiratory surfaces from dehydration, temperature changes, and pathogens 4.Produces sounds for speaking, singing, and other forms of communication 5. Aids in sense of smell

Differences between lymphatic vessels and veins

1.lymph moves more slowly than blood in veins. 2.lymphatic vessels have more branches than veins. 3.lymphatic capillaries are closed at one end and blood capillaries are open at both ends. 4. lymphatic capillaries walls have large pores and stretch to allow entry of interstitial fluid, white blood cells, pathogens, fat droplets and plasma proteins. Blood capillaries have smaller pores.

fluid that leaves capillaries

15% of the fluid that leaves the capillaries remains in the interstitial space (between the cells) If this fluid is not returned to the bloodstream: the tissues become swollen "edema"

RBC's solve this problem by:

98.5% of 02 is Bound to Hemoglobin 70% of C02 is converted into bicarbonate (HC03-)

Respiratory cycle

A single breath of inhalation (inspiration) and exhalation (expiration)

Factors Affecting the Affinity of Hb for O2

Affinity= binding strength PO2 pH Temperature

Oxygen Transport

After the first 02 binds to iron , the Hb molecule changes shape and more quickly binds a second, third and fourth 02 molecule until it is fully saturated with 02!

Ability to distinguish Self from Non-self.

All body cells (except rbc's) have "Self-Tags" on their surface called MHC proteins Major Histocompatibility Complex MHC molecule: "flag pole" to present antigen --unique to each person. --determined by your genes. --signals your immune system to leave your cells alone!

Residual volume

Amount of air remaining in lungs after maximal exhalation

..

Anatomy of Respiratory System -Physiology of Respiratory System -Pulmonary (Lung) Function -Lung Volumes and capacities -Exchange of O2 and CO2 (reason we have lungs!) -Control of Respiration by CNS

2. Activation and Cell Division

Antigen recognition and costimulation result in T cell activation and cell division, producing active cytotoxic T cells and memory T cells.

1. Antigen Recognition

Antigen recognition occurs when a cytotoxic T cell encounters an appropriate antigen on the surface of another cell, bound to a Class I MHC protein.

Antigens

Antigens are substances recognized as foreign that provoke immune responses. Antigen= "Antibody generator" Antigens can be: Pathogens Parts or products of pathogens Other foreign compounds

Inhalation and Exhalation: Negative Pressure Breathing

As Lung Volume increases--> pressure decreases--> air enters As Lung Volume decreases--> pressure increases-->air out

Autoimmune Disease

Autoantibodies produced and cytotoxic T cells that destroy body's own cells*

1st Line of Defense: External Defenses

Barriers to Entry of Pathogens: block pathogen entry into the body. •Physical Barriers •Chemical Barriers

Hemothorax

Blood accumulating in pleural cavitylung volume reduced-->less airflow

Overall reaction occurs inside rbc's

Carbonic Anhydrase enzyme is inside RBCs! Bicarbonate (HCO3-) diffuses out of RBC in exchange for chloride ion (Cl-) Known as the chloride shift to balance the outrush of negative bicarbonate ions from the rbc. Reactions are rapid and reversible!!

Cardiovascular system Vs Lymphatic system

Cardio: transports blood within blood vessels to the heart (veins) and away from the heart. (arteries) Lymph: transports lymph within lymphatic vessels to the heart. Without your lymphatic system your cardiovascular system could not function!

conscious control

Conscious control resides in the cerebral cortex Able to modify breath to speak and sing Able to hold breath temporarily, but can't override automatic controls located in medulla oblongata indefinitely

Helper T cells, "Commanders" are an important "safety mechanism" that prevents inappropriate B cell or cytotoxic T cell activation!

Costimulation by an activated Helper T cell confirms that antigen recognition has occurred. The Helper T cells releases cytokines that stimulate the specific Cytotoxic T cell or B cells to multiply forming a "clonal army" and memory cells. Prevents Cytotoxic T cells and B cells from mistakenly attacking normal (self) tissues.

partial pressure

Each gas in the air contributes a partial pressure. Partial Pressure (p) is the "concentration" of the gas.

around lung...?

Each lung enclosed by double-layered pleural membrane Parietal pleura: lines inner wall of thoracic cavity and extends over the diaphragm Visceral pleura: covers outer surface of lungs Pleural Cavity : fluid-filled space between layers.

Pulmonary Capillaries and Blood Pressure

Endothelial cells of alveolar capillaries secrete angiotensin-converting enzyme (ACE) ACE is released into the bloodstream and Converts Angiotensin I Angiotensin II Part of the homeostatic mechanism for maintaining BP

Localized tissue response that produces

Four outward signs of inflammation: redness heat swelling Pain

1. Resistance in Respiratory Pathways

How do each of the following affect resistance/airflow in bronchioles? Parasympathetic NS ACh Bronchoconstriction Allergies histamine release Bronchoconstriction Exercise/stress epinephrine Bronchodilation (epinephrine released from adrenal medulla)

Diversity of Antigen Receptors

Human immune system is able to recognize and bind to at least a billion different antigens. Result of genetic recombination: shuffling and rearranging of a few hundred versions of several small gene segments.

Two types of Allergic Responses:

Immediate allergic response: -happens immediately after exposure to allergen -mediated by B cells, antibodies and histamine. Delayed allergic response: -symptoms appear within 2-3 days after first exposure to allergen -mediated by T cells and cytokines

Under-active Immune System

Immune Deficiency Disease occurs when the immune system is not functioning properly. Examples: AIDS and SCID 1. SCID: "bubble boy disease" Severe Combined ImmunoDeficiency -Child is born with defective Helper T cells so the patient is unable to produce B cells or T cells. -Inherited Disorder AIDS : Acquired ImmunoDeficiency Syndrome Helper T cells and macrophages are destroyed by a virus called HIV HIV: Human Immunodeficiency Virus

Pneumonia

Inflammation of alveoli due to infection: fluid leaks into alveoli, bronchioles swell--> narrows passageways-->less airflow

Pneumothorax

Injury to parietal pleura or alveoli Air enters pleural cavity decreased pressure--> collapsed lung. Treatment involves removing air and sealing opening

Innate (nonspecifil) defenses

Innate (nonspecifil) defenses: •Present at birth and do not distinguish between threats •Include: •Physical and Chemical barriers •Phagocytes •Immune surveillance •Interferons •Complement •Inflammation •Fever

Factors that increase 02 release from Hemoglobin:

Low P02 Low pH (acidic) High temperature

Hypoxia

Low tissue oxygen Metabolic activities become limited

Two Types of MHC

MHC I found on all nucleated body cells (not rbcs) MHC II found on Macrophages, Lymphocytes, Dendritic Cells (macrophages in skin, lymph nodes and spleen)

Pleural Cavity: Pleural fluid:

Pleural Cavity: space between pleural membranes Pleural fluid: secreted by pleural membranes -Prevents friction when lungs move. -Holds lungs in place -Provides negative pressure too keep lungs inflated

The Basis of ACTIVE IMMUNITY

Primary Immune Response: After first exposure to antigen Antibody production begins 3-6 days after exposure to antigen, peaks at 10-12 days declines in about a month. Memory cells remain (up to 20yrs!) Secondary Immune Response: After second exposure to antigen Antibody production is rapid, (hours), peaks in days, larger and longer -lasting Can be years after first exposure Reason why vaccination is effective! Due to large number of Memory Cells that are "primed" for the arrival of antigen!

Structure of Alveoli Type II Pneumocytes (septal cells)

Produce surfactant Helps keep alveoli open by reducing surface tension Lack of surfactant triggers respiratory distress syndrome: alveoli collapse and cannot breathe. Babies born prematurely (before 30 weeks) lack surfactant and are given surfactant through a breathing tube to prevent their lungs from collapsing.

Respiratory tract

Respiratory tract refers to passageways carrying air to and from lungs Divided into two portions: -Conducting portion: "getting air in" From nose to larger bronchioles Filters, warms, and humidifies air -Respiratory portion: "end of line" Smallest bronchioles and alveoli Where gas exchange occurs

Emphysema

Shortness of breath due to destruction of alveoli and respiratory bronchioles. Caused by smoking , air pollution etc.

3rd Line of Defense

Specific Defenses/ Immune Response • Involves the Activity of Lymphocytes called T-cells and B-cells. The "immune response" targets specific enemies without harming healthy cells.

Factors that increase lung compliance:

Surfactant: lowers surface tension in alveoli which keeps alveoli from collapsing.

3.Destruction of Target Cells

The active cytotoxic T cell destroys the antigen-bearing cell. It may kill the target cell in several ways.

larynx

The larynx is a set of hyaline cartilages that act as a passageway for air connecting the pharynx --> trachea

anatomy of Pulmonary Lobule

Thick layer of smooth muscle around bronchiole : -bronchoconstriction (parasympathetic stimulation) -bronchodilation (sympathetic stimulation) -Extreme bronchoconstriction can occur during allergic reactions such as asthma.

Antibodies

do NOT kill pathogen directly! Antibodies bind to pathogen and form an antibody-antigen complex that: 1. immobilizes pathogen "stick a tree branch in tire spokes" 2. Tag pathogens for destruction by macrophages. 3. Cause pathogens to stick together, "agglutinate" to make it easier for macrophages to engulf. 4. Activate complement Antibodies do NOT kill pathogen directly "PLAN" of attack. Precipitation, Lysis (complement), Agglutination, Neutralization

Tidal volume (TV)

Volume of air moved into or out of lungs in single respiratory cycle (one breath) ~500mL "in and out like ocean tides"

Action of Interferon

When a virus infects a body cell, the cell releases Interferon , that warns healthy cells to produce antiviral proteins that interfere with virus replication. (Interferon is used to treat viral hepatitis, genital warts and leukemia)

Alveoli

When the conducting zone ends at the terminal bronchioles, the respiratory zone begins The respiratory zone terminates at the alveoli, the "air sacs" found within the lungs

Immunity

ability of the body to defend itself against foreign invaders.

Delayed Allergic Response..dont need to know

activation of T cells and allergic response within 2-3 days 1. Allergen forms a chemical bond with proteins on the surface of skin cells that tricks the T cells to perceive that a pathogen has invaded a skin cell. 2. T cells release cytokines that cause inflammation within 2-3 days. 3. Poison ivy, TB skin test for tuberculosis, detergents, cosmetics, nickel in jewelry. (contact dermatitis, excema) Treatment: corticosteroids( cortisone/prednisone) to prevent T cells from releasing cytokines.

Oropharynx

air, liquid and food From soft palate to base of tongue palatine and lingual tonsils stratified squamous

Laryngopharynx

air, liquid and food Hyoid bone to entrance of esophagus stratified squamous

Immune system

complex group of cells, chemicals and structures that function to protect the body from foreign invaders

Respiratory Dead Space

conducting airways with air that does not undergo respiratory gas exchange.

The larynx

contains vocal folds, which produce sound when they vibrate

Pus

discharge produced at the infection site containing dead phagocytes, dead pathogens, tissue fluid and cell debris. (an abscess is pus that is trapped and cannot drain)

Allergy

inappropriate immune response to a harmless antigen called an allergen.

Hilum

indentation where blood and lymphatic vessels communicate.

Passive immunity

individual is given antibodies from another person or animal to fight an existing infection if there is not enough time for the patient to produce their own antibodies. Advantage: fast-acting protection Disadvantage: short-lasting immunity antibodies disappear from the body quickly MEMORY CELLS ARE NOT PRODUCED! Examples: 1.naturally as antibodies are passed from mother to baby during pregnancy or thru breastfeeding 2. artificially via an injection of antibodies from another person or animal that has been exposed to the antigen: -snake anti-venin -tetanus anti-toxin -anti-Rh antibodies given to Rh- mother to protect her Rh+ baby. Sometimes a person's immune system reacts in a way that is harmful to their body!

Rhinitis

inflammation of respiratory mucosa Infection spreads from upper to lower respiratory tract.

In order for a Helper T cell to become activated....

it must be "presented" with the antigen by an Antigen Presenting Cell. (APC) 1. APC captures foreign invader presents antigen on its surface within MHC 2. APC "tells" TH cell"this is what invader looks like" it's ok to command specific Cytotoxic T cells and B cells to multiply and form a clonal army and memory cells!!!!

The Respiratory Mucosa

lines respiratory airway (conducting portion)

Lymph nodes store 2 types of white blood cells that remove pathogens

macrophages and lymphocytes -Color scanning electron micrograph ( x1000) of a section through a lymph node, showing white blood cells (macrophages and lymphocytes ) waiting to attack and destroy foreign and damaged cells. (a few red blood cells are also present)

Vital Capacity

max air exhaled after max inhale VC = TV + ERV + IRV Total lung capacity= VC + RV

Central and peripheral chemoreceptors respond to....

pCO2 (H+) by increasing respiratory rate.

Nose

passageway for air External nares (keep passageway open!) Nasal hyaline cartilage (keep nares open!)

Complement

proteins in blood plasma that "assist" other defenses. 1. Kills pathogens directly: -Forms a membrane attack complex that punches holes in bacteria and viruses that causes them to burst 2. Coats bacteria to make them more susceptible to attack by phagocytes.

2. Vaccination

provides long-lasting immunity to a pathogen without getting sick. Vaccines contain an Antigen that "trains" your immune system to respond as if it has been infected with the live pathogen. Memory T and B cells are produced that remember the antigen and protect you from future infections

Sneezing

removes mucus and microorganisms from the body

Elephantiasis

severe swelling of tissues due to a parasitic worm that blocks lymphatic vessels causing lymphedema (swelling). Interstitial fluid accumulates and affected area swells. (Parasitic Worm is transmitted to humans by mosquitoes. (Microscopic size))

THYMUS GLAND

site of T lymphocyte maturation (Tcell) 1. Found in lower neck above the heart 2. Largest in children and shrinks as we age 3. T cells move from the red bone marrow to the thymus where they mature and are "trained" to tolerate "self" cells and to recognize foreign cells (only 2% of T cells are allowed to leave the thymus)

1. Natural exposure

to live pathogen: you get sick following infection with the live virus or bacteria. Within 7-14 days your immune system produces activated T cells, B cells, antibodies and Memory cells and then you recover. Your Memory T cells and B cells remember the antigen so that if you are exposed again, the immune system reacts quickly with a secondary immune response.

Cancer

uncontrolled growth of abnormal cells -Impairs air flow, gas exchange, blood flow -One-third of all U.S. cancer deaths Causes: 90% of cases associated with smoking Radon gas Workplace chemicals such as asbestos

Nasal Cavity

warms, humidifies and filters air Lined with ciliated epithelium secretes mucus. Olefactory epithelium near superior nasal concha. extensive network of veins warm inhaled air Water from mucus evaporates to humidify inhaled air Nasal conchi swirls air and traps particles Nose hairs and mucus trap particles

Antiviral Proteins: Interferon

• Proteins secreted by virus-infected cells that INTERFERE with viral replication and protect neighboring cells from viral infection!

Anti-histamines

•Blocks histamine action and decreases swelling, redness and heat. •Nasal congestion is due to swelling in the nasal tissues due histamine action. Antihistamines prevent histamine from working so the capillaries in the nose return to their normal "non-leaky" state and the swelling diminishes.

Immune Surveillance by NK Cells

•Constant monitoring of normal tissues by NK (natural killer) cells. •Cancer cells often contain tumor-specific antigens. •NK cells recognize as abnormal and destroy •Respond rapidly •NK cells recognize bacteria, foreign cells, virus-infected cells, and cancer cells •Secrete perforins that create holes in the target cell's plasma membrane, killing the cell

Patient with mono

•EBV infection impacts lymphocytes •Virus infects B lymphocytes •Causes B lymphocytes to proliferate (large #s, oversized cells) •Many symptoms, including: •Swollen glands •Sore throat: Inflamed tonsils •Swollen, tender spleen...possible rupture. •If rupture... what happens? (under 12 y.o.can regenerate if a small part is left in the body)= bleed to death

Phagocytes

•Engulf and destroy foreign compounds and pathogens •"First line of cellular defense" against pathogenic invasion. MICROPHAGES 1. Neutrophils •Phagocytize cellular debris or bacteria 2. Eosinophils •Phagocytize foreign compounds and antibody-coated pathogens MACROPHAGES(derived from monocytes located in tissues) • Fixed : permanent residents of certain organs • Free : travel throughout body -Phagocytosis of a bacteria by a macrophage -Phagocytosis of an anthrax bacteria by a neutrophil

2nd Line of Defense: Nonspecific defenses

•Fights infection without identifying the invader. •Immediate •No memory

Physical Barriers that block pathogens from entering the body

•Intact Skin •Hair in the nostrils filters the incoming air. •Mucous membranes in respiratory tract, digestive tract, and reproductive tract secrete mucus that traps bacteria, dust and other particles. •Cilia in respiratory tract sweep mucus with the trapped particles upward until it is swallowed or expelled by sneezing, coughing or blowing the nose. •Helpful bacteria in intestine prevent harmful bacteria from entering. •Vomiting, coughing, swallowing, urination, defecation removes pathogens

How does fluid and large substances enter into the lymphatic capillaries?

•Lymphatic capillaries have wide spaces between overlapping cells so that fluid and large particles (proteins, fats, bacteria) can easily enter. •Lymphatic capillaries are closed at one end so that the lymph flows in one direction towards the heart (Blood capillaries are open at both ends!)

Secondary lymphoid tissues and organs

•Sites where lymphocytes are activated and cloned •Include: MALT(lymphoid tissue in respiratory, digestive, urinary and reproductive), lymph nodes and spleen,

Primary lymphoid tissues and organs

•Sites where lymphocytes are formed and mature •Include: red bone marrow and thymus

Chemical Barriers that block pathogens from entering the body

•Sweat, saliva and tears contain antimicrobial chemicals •Oil secreted by oil glands blocks pathogens •Earwax traps small particles and pathogens. •Acid secreted into stomach and vagina kills pathogens

Body defenses

•Two general categories of body defenses work together to provide resistance 1. ​Innate (nonspecific) immunity •​Provides nonspecific resistance •No memory, present at birth 2. ​Adaptive (specific) immunity •Provides specific resistance •Memory