224 Lecture Exam 3 Flashcards
Immune system
Not an organ system
Throughout the body
Functions of the lymphatic system
Immunity Lipid absorption Fluid recovery Transport lymph** Gathering fluid from lymphatic system
Lacteals
Special lymphatic vessels
In the small intestines and absorb dietary lipid that are not absorbed by the blood capillaries
What is lymph?
-Clear, colorless fluid, similar to plans a, but much less proteins
Largest lymphatic vessels
Collecting ducts
Right lymphatic duct
Receives lymph from right arm, right side of head and thorax; empties into right subclavian vein
Thoracic duct
Larger and longer, begins as a sac in abdomen called the cisterns chili; receives lymph from below diaphragm, left arm, left side of head, neck, and thorax; empties into left subclavian vein
Neutrophils
Antibacterial
Natural killer (NK) cell
attack and destroy bacteria, transplanted tissue, host cells infected with viruses or that turned cancerous
T lymphocytes (T cells)
Mature in thymus
B lymphocytes (B cells)
Activation causes proliferation and differentiation into plasma cells that produce antibodies
Lymphatic (lymphoid) tissue
Aggregations of lymphocytes
Lymphatic nodules (follicles)
Dense masses of lymphocytes and macrophages
Aggregated lymphoid nodules: dense clusters in the ileum, the distal portion of the small intestine
Three main sets of tonsils
Palatine tonsils
Lingual tonsils
Pharyngeal tonsil
Palatine tonsils
Pair at posterior margin of oral cavity
Most often infected
Largest
Mainly taken out
Lingual tonsils
Pair at root of tongue
Pharyngeal tonsil
Single tonsil on wall of nasopharynx
Innate immunity
Nonspecific defense mechanisms has physical barriers (skin, chemicals in blood) and immune cells
Adaptive immunity
Antigen-specific immune response. Antigen has to be processed and recognized. Army of immune cells attack antigen
Pathogens
Agents capable of producing disease
-include viruses, bacteria, and fungi
Three lines of defenses against pathogens
First: skin and mucous membranes
Second: several innate defense mechanisms
- leukocytes and macrophages, anti microbial proteins, natural killer cells, inflammation, and fever
Third: adaptive immunity
-defeats a pathogen and leaves the body with a “memory” of it so it can defeat it faster in the future
Two families of antimicrobial proteins
Interferons
Complement system
Interferons
Of no benefit to the cell that secreted them
- secreted by certain cells infected by viruses
- alert neighboring cells and protect them from becoming infected
- bind to surface receptors on neighboring cells
- activate NK cells to destroy infected cells
Phagocytes
Cells that engulf foreign matter
Neutrophils
Wander I connective tissue killing bacteria
- can kill using phagocytosis and digestion
- can kill by producing a cloud of bactericidal chemicals
Eosinophils
Found especially in mucosa membranes
-guard against parasites, allergens (allergy-causing agents), and other pathogens
Basophils
Secrete chemicals that aid mobility and action of other leukocytes
- histamine: a vasodilator, which increases blood flow
- leukotrienes: activate and attract neutrophils and eosinophils
Monocytes
Transform into macrophages
Lymphocytes
Three basic categories: T, B, and NK cells
-NK cells are part of innate immunity, all others are part of adaptive immunity; helper T cells function in both
Three characteristics distinguish adaptive immunity from innate immunity
- systemic effect: throughout the body
- specificity: immunity directed against a particular pathogen
- memory: when reexposed to the same pathogen, the body reacts so quickly that there is no noticeable illness
Cellular (cell-mediated) immunity
- lymphocytes directly attack and destroy foreign cells or diseased host cells
- rids the body of pathogens that reside inside human cells, where they are inaccessible to antibodies
Humoral (antibody-mediated) immunity
- mediated by antibodies that do not directly destroy a pathogen but tag it for destruction
- many antibodies are dissolved in body fluids (“humors”)
Natural active immunity (adaptive immunity)
Production of one’s own antibodies or T cells as a result of infection or natural exposure to antigen
Artificial active immunity (adaptive immunity)
Production of one’s own antibodies or T cells as a result of vaccination against disease
Natural passive immunity (adaptive immunity)
Temporary immunity that results from antibodies produced by another person
-fetus acquires antibodies from mother through placenta, milk
Artificial passive immunity (adaptive immunity)
Temporary immunity that results from the injection of immune serum (antibodies) from another person or animal
-treatment for snakebite, botulism, rabies, tetanus, and other diseases
Antigen-presenting cells
T cells cannot recognize antigens on their own. Antigen-presenting cells (APCs) are required
-dendritic cells, macrophages, reticular cells, and B cells function as APCs
Role of the cytotoxic T cell
Cytotoxic T (Tc) cells are the only T cells that directly attack other cells Docking itself on cell and deliver perforin and granzymes-kill cells in same manner NK cells Interferons- inhibits viral replication- recruit and activate macrophages
Humoral immunity
Humoral immunity is a more indirect method of defense than cellular immunity
Works in three stages
Recognition
Attack
Memory
B lymphocytes
produce antibodies that bind to antigens and tag them for destruction
Functions of the respiratory system
Gas exchange, communication, olfaction, and acid-base balance
What is the role of CO2
pH balance
Cells of the alveolus
Squamous (type I) Great (type II) Alveolar macrophages (dust cells)
Squamous
Thin, broad cells that allow for rapid gas diffusion
Cover 95%
Great
Round to cuboidal cells that cover the remaining 5% of alveolar surface
Repair the alveolar epithelium when the squamous (type I) cells are damaged
Alveolar macrophages
Most numerous of all cells in the lung
Keep alveoli free from debris by phagocytizing dust particles
Alveoli
Each alveolus surrounded by a basket of capillaries supplied by the pulmonary artery
Two factors to influence airway resistance
Diameter of the bronchioles
Pulmonary compliance
Composition of air
- 78.6% nitrogen
- 20.9% oxygen
- 0.04% carbon dioxide
- 0% to 4% water vapor, depending on temperature and humidity
- Minor gases argon, neon, helium, methane, and ozone
Dalton’s law
Total atmospheric pressure is the sun of the contributions of the individual gases
Gas transport
The process of carrying gases from the alveoli to the systemic tissues and Vice Versa
Systemic gas exchange
The unloading of O2 and loading of CO2 at the systemic capillaries
What does the addition of CO2 generate?
HCO3- and H+
H+ binds to hemoglobin allowing oxygen to be put into blood
Four body systems carry out excretion
Respiratory system
Integumentary system
Digestive system
Urinary system
Organs of urinary system
Kidney
Ureter
Urinary bladder
Urethra
Urea formation
Proteins are catalyze to urea
Nephrons
1.2 million of them
Renal corpuscle
Filters the blood plasma
Renal tubule
Long, coiled tube that converts the filtrate into urine
Renal corpuscles consist of
Glomerus and a two layer glomerular capsule
Filter at ion occurs in podoctyes
Proximal convoluted tubule
PCTs alone account for about 6% of the one’s resting ATP and calorie consumption
The role of collecting ducts
concentrate the urine (hypertonic) and conserve water (wastes and NaCl pass though)
The goal: get as salty as possible to maximize water reabsorption
Distal convoluted tubule and collecting duct
Regulated by aldosterone
Micturition
What eliminates urine
Ureters
Transport urine from kidneys to urinary bladder
Appearance of urine
Urochrome pigment causes yellow color
Pyuria is pus in urine
Hematuria is blood in urine
Osmosis
Movement of water from one fluid compartment to another
Osmoreceptors
In hypothalamus (govern fluid intake) -respond to angiotensin II
How to control water output
Only way to control water output significantly is through variation in urine volume
- kidneys cannot replace water or electrolytes
- can only slow rate of water and electrolyte loss until water and electrolytes can be ingested
Sweating vs cold air
raises blood pressure which inhibits ADH secretion
Cold air is drier and increases respiratory water loss also reducing blood volume
Edema
Abnormal accumulation of fluid in interstitial spaces, causing swelling of tissues
Primary role of Aldosterone
Adjusting sodium excretion and increases Na+ reabsorption and K+ secretion
