ZOO 251 Florence Wen Exam 2 SELU

immune system

-not an organ system

-refers to population of cells found in all organs

-defends body from agents of disease/ pathogens

lymphatic system

-a true organ system

-immune cells concentrate here

-network of organs, vein-like vessel

>recover tissue fluid

>inspect fluid for pathogens or infected cells

> helps to activate immune response

>return fluid to bloodstream

lymph nodes, spleen, thymus, tonsils, red bone marrow

what are five organs in the lymphatic system

fluid recovery, immunity, and lipid absorption

what are the 3 main functions of the lymphatic system

fluid recovery

Lymphatic System Functions:

-fluids moves from blood capillaries to tissues

-capillaries reabsorb about 85% water from digestive tract

-reabsorbs excess fluids and returns them to the bloodstream

-15% blood=2-4 L of water and 1/4-1/2 lb. of plasma protein found in body

immunity

Lymphatic System Functions:

-picks up foreign cells and chemicals from tissues

-before extra fluid gets absorbed into blood stream, fluid passes through lymph nodes (immune cells)

-immune response to anything potentially harmful

lipid absorption

Lymphatic System Functions:

-in small intestines, special lymphatic tissues (lacteals)

-absorb lipids not absorbed by blood capillaries

lacteals

specialized lymph vessels in the small intestine that absorb fat into the bloodstream

lymph

Components of Lymphatic System:

-excess fluid that is reabsorbed

-moves around in your body

-recovered fluid

lymphatic vessels

Components of Lymphatic System:

-transports lymphs through body

lymphatic tissues

Components of Lymphatic System:

-places in body where lymphocytes and macrophages (immune cells) are concentrated and populate organs

lymphatic organs

Components of Lymphatic System:

-immune cells are concentrated here

lymph

Components of Lymphatic System:

-clear colorless fluid

-similar to plasma, but is low in protein

-tissue fluid taken up by lymphatic vessels

-contains macrophages, hormones, bacteria, viruses, even traveling cancer cells

whether or not we've eaten, where they are coming from

composition of lymph:

-what can causes differences in the composition in lymphs

-lymph from intestines milky from lipids

-large number of lymphocytes

lymphatic capillaries > collecting vessels > lymphatic trunks > collecting ducts > subclavian veins

route from tissue fluid back to bloodstream through lymphatic vessels

lymphatic capillaries

Route from Tissue Fluid to Bloodstream:

-similar to blood capillaries but closed on one end

-woven into capillary beds of our blood capillaries

-cells not joined by tight junctions like blood capillaries

-gaps for bacteria, lymphocytes, etc to enter with tissue fluids

-flow similar to veins (low pressure systems)

-have valves, similar to veins, to prevent backflow of lymph fluid

collecting vessels

Route from Tissue Fluid to Bloodstream:

-slightly larger than capillaries

-lymphatic capillaries converge to collecting vessels

-travel alongside veins and arteries

-lymph nodes

>receive and filter lymph

> immune cells monitor for foreign antigens

> phagocytize bacteria

lymphatic trunks

Route from Tissue Fluid to Bloodstream:

-collecting vessels connect to these

-there are 6 types: jugular, subclavian, bronchomediastinal, intercostal, intestinal, lumbar

collecting ducts

Route from Tissue Fluid to Bloodstream:

-largest of lymphatic vessels

-the 6 lymphatic trunks converge into 2 of these

-right lymphatic duct

-thoracic duct

right subclavian vein

what does the right lymphatic duct drain into

left subclavian vein

what does the thoracic duct drain into

below diaphragm, left arm, left side of head, and thorax

where the the thoracic duct receive lymph from

right arm, right side of head, and right thorax

where does the right lymphatic duct receive lymph from

right lymphatic collecting duct

collecting ducts:

-receives lymph from right arm, right side of head, and right thorax

-drains into right subclavian vein

thoracic collecting duct

collecting ducts:

-receives lymph from below diaphragm, left arm, left side of head, and thorax

-drains into left subclavian vein

lymphedmea

Lymphatic Disorders:

-caused by blocked lymph drainage

-lymph accumulated in infected area

-lymph vessels blocked by cancer or parasites

-tight clothing constricts vessels- edema (swelling of tissues)

elephantitis

Lymphatic Disorders:

-extreme case of edema

-caused by parasitic roundworm (carried by infected mosquitoes)

-roundworms infect lymph nodes and block them

-interferes with lymph flow and recovery of tissue fluid

-causes excess fluid to accumulate in lymphatic system and causes swelling of legs

lymphocytes

primary immune cells in lymphatic system

-T cells

-B cells

-NK cells

lymphopoiesis

production of lymphocytes

-starts in red bone marrow with hemocytoblasts that become lymphoid stem cells which either become a B or NK cell in bone marrow or a T cell in thymus

hemocytoblasts

cells found in bone marrow that become lymphoid stem cells, and eventually lymphocytes (B, NK,or T cells)

T cells

Lymphocytes:

-lymphocytes that mature in the thymus

-make up 80% of circulating lymphocytes

-consists of: cytotoxic, helper, and suppressor

cytotoxic T cells

Types of T Cells:

-attack foreign cells or body cells with viruses

helper T cells

Types of T Cells:

-stimulate other T cells and B cells

suppressor T cells

Types of T Cells:

-inhibit other T cells and B cells

B cells

Lymphocytes:

-differentiate into plasma cells that secrete antibodies to help with immune response

-mature in bone marrow

NK cells

Lymphocytes:

-migrate throughout our body

-look for abnormal cells in body to destroy

-attack and destroy any bacteria, transplanted tissues, or infected host cells with viruses or turned cancerous

humoral immunity

Types of Immunity:

-B cells

-antibody mediates

-tag pathogens for destruction

-extracellular pathogens such as toxins, venoms, allergens

cellular immunity

Types of Immunity:

-T cells

-lymphocytes (cell mediated)

-directly attack and destroy foreign cells, diseased host cells

-attack pathogens inside human cells (inaccessible to antibodies)

-attack intracellular pathogens like cancer cells, parasitic worms, cells from transplants

humoral and cellular

what are the two types of immunity

lymphoid tissue

connective tissues dominated by lymphocytes

-loosely scattered cells in mucous membrane to compact cell populations in lymphatic organs

EX) MALT (mucosa-associated lymphoid tissues)

> found in respiratory, digestive, urinary, and reproductive tracts

mucosa associated lymphoid tissues

-collection of lymphoid tissues

-found in respiratory, digestive, urinary, and reproductive tracts

lymphoid modules

Lymphoid Tissues:

-masses of lymphocytes

-in areas where pathogens are abundant and always attempt to invade tissues

-constantly in small intestines, at junctions with the large intestine (peyer patches)

-appendix

peyer patches

lymphoid nodules:

-found at junctions between small and large intestines

Lymph nodes, tonsils, spleen, thymus, red bone marrow

name the organs that are involved in the lymphatic system

lymph nodes

Organs of the Lymphatic System:

-very numerous in body (450 in adults)

-composed of: cervical, axillary, abdominal, inguinal, thoracic, and pelvic

-can swell during infection

-filter for our lymph (reabsorbed fluid)

>lymph may contain bacteria, antigens, or other harmful materials

>contain a lot of macrophage lymphocytes to consume foreign material

>lymphocytes respond to antigens

-this is also a site where T and B cells get activated

tonsils

Organs of the Lymphatic System:

-found at entrance to pharynx

-guard against ingested and inhaled pathogens

-3 main sets of these (people have 5 total)

palatine tonsils

Organs of the Lymphatic System:

-pair, posterior to oral cavity

lingual tonsils

Organs of the Lymphatic System:

-pair, root of tongue

pharyngeal tonsils

Organs of the Lymphatic System:

-single, posterior wall pf pharynx

tonsillitis

infection of the tonsils (usually palatine or pharyngeal tonsils)

spleen

Organs of the Lymphatic System:

-posterior to stomach

-largest mass of lymphoid tissue in our body

-extremely fragile organ that can tear easily

-capable of producing blood cells

-acts as a blood reservoir

-helps recycle blood cells

-filters blood

-helps to activate lymphocyte and macrophages in body

-highly vascularized (lots of blood vessels in them)

-contains two main types of tissues (red pulp and white pulp_

red pulp

Spleen Tissues:

-contains erythrocytes

-helps produce blood cells in fetuses

-in case of severe anemia (really low RBC count) spleen will produce RBC

-in an adult spleen, this tissue acts as a reservoir for blood in case we need it

white pulp

Spleen Tissues:

-contains lymphocytes and macrophages

-in adults, this tissue helps get rid of old blood cells

-macrophages phagocytize old blood cells and blood borne bacteria

-filters blood (like lymph nodes do with lymph)

-lymphocytes and macrophages activate immune response when foreign antigen detected

thymus

Organs of the Lymphatic System:

-part of endocrine, lymphatic and immune systems

-houses developing lymphocytes

-secretes thymosins and thymopoietins which help stimulate development and activity of T lymphocyte cells

-if this is removed from a newborn, the baby will never have any immunity and it will wither away

red bone marrow

Organs of the Lymphatic System:

-involved in hemopoiesis (blood formation) and immunity

-important supplier of lymphocytes to immune system

lymphadentitis

Clinical Application:

-inflammation of lymph nodes due to infection

-swollen and painful

-infected glands are large, very tender, and the infection can move to other nodes

lymphoma

Clinical Application:

-cancer in lymphatic system

-cancer cells break lose from other organs and enter lymphatic capillaries and lodge into lymph nodes

-lymph node swollen but usually firm and painless

-fever, sweating, fatigue, pain

-one of the most easily treated cancers

-if caught late, the cancer can spread throughout the body

epithelial barriers (skin, mucous membranes in openings in body),

Immune System:

-first line of defense in body

leukocytes, macrophages, antimicrobial proteins, NK cells, inflammation

Immune System:

second line of defense in body

adaptive immunity

Immune System:

third line of defense in body

-"remember" pathogens to destroy pathogens quickly if they re-enter body

innate immunity

Immune System:

-defenses we are born with (first and second lines of defense)

adaptive immunity

Immune System:

-when your body adapts to environmental pathogens

-you are not born with this defense

-third line of defense

-a little bit different in everyone

-body becomes less vulnerable to illness

local

Innate Immunity:

-fights pathogens at point of invasion (itchy rash, mosquito bite)

-little effect anywhere else in body

Exception: fever (systemic effect)

nonspecific

Innate Immunity:

-works against broad array of pathogens

lack memory

Innate Immunity:

-has not had prior exposure to pathogen

innate immunity

this immunity is usually very localized, nonspecific, and lacks memory

Leukocytes

second line of defense

neutrophils

Leukocytes:

-wander connective tissues, kill bacteria

-phagocytosis (engulfs microbes)

-respiratory burst to destroy bacteria it's trying to kill

respiratory burst

Leukocytes:

neutrophils will send out hydrogen peroxide, superoxide anions, and hypochlorite to kill microbes

eosinophils

Leukocytes:

-found in mucous membranes

-good to fight off parasites and allergens

-undergoes phagocytosis

-limits inflammation

-promotes basophils and mast cells to come help destroy pathogens

basophil

Leukocytes:

-aid other leukocytes

-have leukotrienes to activate and attract neutrophils and eosinophils to come to a specific area

-vasodilator (histamine)- increases blood flow to certain areas

-heparin (anticoagulant) to allow better blood flow for leukocytes to get to an area

vasodilator

a histamine that increases blood flow to certain areas

heparin

an anticoagulant to allow better blood flow for leukocytes to get to an area

lymphocyte

Leukocytes:

-T cells (80%)

-B cells (15%)

-NK cells (5%)

monocytes

Leukocytes:

-very large agranulocytes

-migrate from blood to connective tissues, transform to macrophages

interferons

Immune System:

-proteins that ares secreted by our cells that are infected with viruses

-induces synthesis of antiviral proteins

-activate NK cells to come to area to destroy the entire cells

-will also signal to neighboring, infected cells to undergo apoptosis

apoptosis

programmed cell death

fever

body temp is above 37.2 degrees C (99 degrees F)

-systemic immune response

-Causes: trauma, infections, drug reactions, brain tumors, etc

-beneficial b/c it promotes interferon activity

-also inhibits reproduction of bacteria and viruses (too hot)

-increased metabolic rate

-increases tissue repair

Reye syndrome

Clinical application:

-extremely rare

-usually happens with children under age of 15

-usually happens following chicken pox or flu

-Symptoms: Swelling of brain neurons which causes neurons to die from hypoxia which can cause mental retardation

-pressure from brain causes nausea, vomiting seizure, coma

-fatty degeneration of liver

-about 30% of victims die from this

-caused by: use of aspirin to control fever

inflammation

takes place when it is a localized defense procedure (tissue injury like a cut or infection)

-helps limit spread of pathogens and destroys them

-removes debris of damaged tissue

-tissue repair

-redness, swelling, pain, heat

redness, swelling, pain, and heat

four sings of inflammation

mobilization of defenses, containment and destruction of pathogens, tissue cleanup and repair

major processes of inflammation

adaptive immunity

Immune System:

-systemic effect (acts through entire body)

-specific (directed against a specific pathogen)

-has memory (able to send quick reaction to pathogen)

> no noticeable illness

ATP

what does metabolism require

O2

what does ATP synthesis require?

CO2

what does ATP synthesis generate

supply blood with O2, eliminate CO2

why do we breathe?

deliver air to lungs

what does the respiratory system do

alveoli

tiny sacs of lung tissue specialized for the movement of gases between air and blood

gas exchange, communication, olfaction

what are the main functions of the respiratory functions?

acid-base balance, blood pressure regulation, blood and lymph flow, blood filtration, expulsion of abdominal contents

what are some other functions of the respiratory system that are not the major three?

gas exchange

Functions of the Respiratory System:

-provides O2 and CO2 exchange between blood and air

communication

Functions of the Respiratory System:

-speech and other vocalization (laughing, crying, etc)

olfaction

Functions of the Respiratory System:

-provides us with sense of smell

-important for social interaction, food selection, avoiding danger

nose/ mouth, pharynx, larynx, trachea, bronchi, lungs

what are the main organs involved in our respiratory system

conducting zone

passages for airflow in resp. system

-this is from nostrils to major bronchioles

-too thick for O2 to go into blood

respiratory zone

area where gas exchange actually takes place

-alveoli and other gas exchanging regions

upper respiratory tract

airway from nose to larynx

-resp. organs in head and neck

EX) sinus infection, runny nose

lower respiratory tract

airway from trachea to lungs

-resp. organs of thorax

EX) bronchitis, pneumonia

nose

Organs of Respiratory System:

-warms, cleanses, and humidifies inhaled air

-detects odors

-amplifies voice

-extends from pair of anterior openings (nostrils)