1. Immune System
Describe the three types of hypersensitivities. When does each begin and how long does it last?
Three different types of hypersensitivities:
Immediate - Begin in seconds, lasts for about ½ an hour
Subacute - Begin in 1 - 3 hours, lasts for 10 - 15 hours
Delayed - Begin in 1 - 3 days
What is responsible for neural control of breathing? Describe the responsibilities of both structures.
Medulla forms the rhythm.
Pons controls regulates the rhythm and smooths the transitions of inspiration and expiration.
What is Boyle's Law?
If temperature remains constant, the pressure of a gas is inversely related to its volume.
What are the functions of saliva? (Describe 4 of 5 for full credit).
Cleanses the mouth
Moistens and dissolves food chemicals
Aids in bolus formation
Contains enzymes that begin the breakdown of starch
Immune function (lysozyme, IgA, defensins and a cyanide compound
List the four types of teeth.
Incisors
Canines
Premolars
Molars
Describe immunological memory.
Cell proliferation and response:
Primary immune response (first exposure): lag time of 3-6 days (proliferation and differentiation of plasma cells)
Secondary immune response: faster, longer, more effective, as immune system is primed for the antigen. There is an increased titer level in the blood for antibodies
How does CO2 travel in the body?
Transported in three ways:
Dissolved in plasma (7-10% as CO2)
Chemically bound to Hb (~20% as carbaminohemoglobin)
As Bicarbonate ion in plasma (~70% converted to HCO3-)
What is insensible water loss?
This term refers to water loss due to the following:
Transepidermal diffusion: water that passes through the skin and is lost by evaporation
Evaporative: water loss from the respiratory tract
Describe the two intrinsic nerve plexus.
Submucosal: regulates glands and smooth muscle of the tunic
Myenteric: control GI tract motility (i.e., segmentation and peristalsis)
Describe three diseases of the teeth. How can one of these affect another system of the body?
Diseases:
Dental caries (cavities)
-- decay by bacterial action
Periodontal disease
-- plaque buildup causing infection in surrounding tissues
-- destroys periodontal ligament
Gingivitis
-- infection of the gums
Describe T-Cell activation AND T-Cell response.
Two step process
Antigen binding
T-cell antigen receptors bind to an antigen-MHC complex
Termed naïve T-cells at this stage (activated)
Costimulation
Must recognize costimulatory signals (safeguard)
Activated T-cell enlarges and proliferates forming a clone
Perform functions according to the T-cell class
Must recognize both self and non-self (double recognition)
Accomplished using MHC proteins
Class I
Recognized by CD8, displayed by most cells. Synthesized in the ER and passed to Plasma membrane for implantation
Endogenous antigen: foreign proteins synthesized and displayed
Class II
On B, T, and antigen presenting cells. From catabolized proteins (exogenous proteins) that are repackaged (Golgi) and displayed
Describe the Bohr Effect.
Increased activity raises the temperature of an area, which shifts offloading of oxygen to those tissues.
What is diffusion and how is affinity affected by it?
The movement of molecules from higher concentration to lower concentration until equilibrium is reached. Higher affinity will disallow movement by diffusion, while low affinity allows for diffusion of gasses.
Describe the papillae of the tongue. (Give 3 of 4 for full credit)
1. Filiform—whitish, give the tongue roughness and provide friction
2. Fungiform—reddish, scattered over the tongue , house taste buds
3. Circumvallate (vallate)—V-shaped row in back of tongue, house taste buds
4. Foliate—on the lateral aspects of the posterior tongue, house taste buds used in infancy and early childhood
List and describe the secretions of the four types of cells in the stomach.
Mucous neck cells: Acidic mucous
Parietal (oxynetic) cells: HCl and intrinsic factor (for B12 absorbtion in SI)
Chief (zygomatic) cells: Pepsin (protein digestion)
Enteroendocrine cells: Hormones to regulate digestion: gastrin, histamine, endorphins, serotonin, cholecystokinin, somatistatin
Describe PLAN and its components.
Compliment
Against cells (bacteria, etc), binding causes a 3D change and exposed complement binding sites, leading to cell lysis
Neutralization
Block specific sites on the antigen (i.e. exotoxins), minimizing the toxic effect of the antibody. Toxins are unable to be released. Eventually, antibody is phagocytized
Agglutination
Cross-linking of antigen-antibody complexes, causing clumping. IgM especially effective
Precipitation
Soluble molecules (not cells) are cross-linked into complexes and settle out of solution.
Eventually, both types phagocytized
Describe the role of carbonic anhydrase in the tissues and at the lungs.
(slide 86-90)
Describe the importance of ventilation-perfusion coupling.
There must be a coupling between the amount of gas in the alveoli (ventilation) and the blood flow in the capillaries (perfusion)
Describe the 4 layers of the Alimentary Canal and their functions.
(slides 16-24)
Describe the histology of the small intestine wall.
(slides 62-64)
Describe all five classes of immunoglobulins, their type, where they may be found, and their functions.
IgM: pentamer
IgA: dimer
IgD: monomer
IgG: monomer
IgE: monomer
Ig M – a potent agglutinating agent and activates complement; circulates in the blood plasma
Ig A – found in body secretions such as saliva, sweat, intestinal juices, milk and helps prevent attachment of pathogens to epithelial cells
Ig D – virtually always attached to a B cell and functions as an antigen receptor; important in B cell activation
Ig G – most abundant antibody in plasma accounting for 75-85 % of circulating antibodies – protects against bacteria, viruses and toxins; crosses the placenta and confers passive immunity from mother to fetus
Ig E – secreted by plasma cells – its levels increase during allergic attacks or chronic parasitic infections of the gastrointestinal tract
Describe the movement of oxygen from inspiration to distribution in the tissues. Also describe the movement of CO2 from the tissues to expiration. Include the influence of pressure gradients.
(slide 67)
List the respiratory volumes and their relation to respiratory capacities. (List all for full credit).
Tidal volume (TV): Air in and out normally (500 ml)
Inspiratory reserve volume (IRV): air forced beyond tidal volume (2100-3200 ml)
Expiratory reserve volume (ERV): air forced out of lungs (1200 ml)
Residual volume (RV): air left in lungs, preventing collapse (1200 ml)
Inspiratory capacity (IC): amount that can be inspired after tidal expiration (sum of tidal and inspiratory reserve volumes)
Functional residual capacity (FRC): amount of air left in the lungs after tidal expiration (combined inspiratory and expiratory volumes)
Vital capacity (VC): The total amount of exchangeable air (~4800 ml)
Total lung capacity (TLC): The sum of all capacities (~6000 ml)
Describe chemical digestion and absorption with regard to carbohydrates, proteins, lipids, and nucleic acids.
(slides 94-106)
Describe the three phases of regulation of gastric secretion.
Stimulatory and inhibitory events occur in three phases:
1.Cephalic (reflex) phase: few minutes prior to food entry
2.Gastric phase: 3–4 hours after food enters the stomach – ~half a teaspoon at a time
3.Intestinal phase: brief stimulatory effect as partially digested food enters the duodenum, followed by inhibitory effects (enterogastric reflex and enterogastrones)
(slides 53-58)