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Flashcards in Exam 3 Deck (46):

What is blood made of (in your answer include the fluid, major cell types, and molecules)

.42 Red Blood Cells
---Lymphocytes, monocytes/macrophages, neutrophilis, eosinophils, basophils, HEMOGLOBIN
.01 White Blood Cells
.58 Plasma Volume
---Organic molecules (amino acids, proteins, glucose, lipids, Nitrogeneous waste)
---Trace element/vitamins
---Gases (CO2, O2)


Describe the primary differences between blood, plasma and serum

Blood is composed of plasma and R/W Blood cells.

Serum is the liquid part of blood after coagulation--no clotting factors like fibrinogen

Plasma is the liquid, cell-free part of blood that has been treated with anti-coagulants.


Describe how we prevent stored whole blood from clotting

Chelators like EDTA or Citrate (Ca2+) are used to prevent clotting in the blood when it's stored. Ca2+ is required for several steps of the coagulation cascade, by removing Ca2+ from the blood, coagulation is ceased.


Draw a diagram of the human heart and label its parts and major vessels


Vena Cava-rA-(tricuspid valve)-rV-(pulmonary valve)-Pulmonary Artery-lungs-Pulmonary Vein-lA-(mitral valve)-lV-(aortic valve)-Aorta


Provide a diagram that shows how blood flows through the heart


Vena Cava-rA-(tricuspid valve)-rV-(pulmonary valve)-Pulmonary Artery-lungs-Pulmonary Vein-lA-(mitral valve)-lV-(aortic valve)-Aorta


Provide a diagram showing the spread of electrical excitation in the human heart and the corresponding signal measured via an ECG


SA-Bachman's bundle passes signal to left Atria, both r/l atrium contract together-

AV--signal received from SA node. slowly passes signal to ventricles. Signal passes down bundle of HIS and back up outer wall of both ventricles. V's contract together from bottom up.


Describe what a left ventricular assist device (LVAD) is and does

Bridge to transplant. The pump drains the left ventricle and pumps the blood into the aorta and out to the rest of the body. it aids by relieving the load and allowing the heart to heal.


Provide a diagram that compares blood pressure the velocity of blood flow and total area of the large arteries, arerioles, capillaries, venules and veins


tricolored graph


What are the three layers of tissue that make up a blood vessel and provide one characteristic that is different between an artery and a vein

1. Endothelium
2. Smooth Muscle
3. Fibrous connective tissue

veins have less smoothe muscle. Veins have a larger mean diameter and a smaller mean wall thickness.


What is atherosclerosis? Describe on bioenineering approach for its treatment

Narrowing of an artery's lumen as the result of material build up or wall thickening (stenosis) Angioplaty with drug eluting and bioresorbable stents. Stents are used to prevent restenosis


EKG wave

P-atrial depolarization
S)-Ventricular depolarization
T-ventricular repolarization


Define Excretion

Process by which products of metabolism and other non-useful materials are eliminated from an organism.

CO2, H2O, undigested materials


How does the major blood supply of the liver differ from that of the kidney?

The liver has 2 sources, Hepatic artery (oxygenated blood) and digestive tract( Hepatic Portal Vein deoxygenated but nutrient and enzyme rich).

Kidney has one source of blood.


What is the structural unit of the liver?
Describe its design

Liver lobule=filter blood
Blood enters at each corner of the hexagon edge (triad)
Blood mixes in sinusoids (capillaries of lobule) (endothelial fenestrations/ no basal lamina)
Drains flow from edge triad to the central vein
Blood is filtered by Hepatocytes (liver cells) and Kupffer Cells (special macrophages of the liver)


What is meant by the term biotransformation and how does it aid excretion of fat soluble compounds

Biotransformation is the chemical modifications made by an organism on a chemical compound (like nutrients, drugs, microbes, toxin.s)
Modifications are made to render molecules more safe or useable, or to facilitate removal/excretion


What is a Kupffer cell? Where are they located? What role do they play in excretion?

Kupffer cells are macrophages found in the liver. They filter blood in the sinusoids (capillaries). Phagocytizes pathogens or damaged red blood cells and platelets.


Describe the lymphatic system and its role in the body

Drainage system for allt organs/tissues
contains 3L lymph/ lymphocytes/waste products
Processed in Lymph nodes, GI tract, kidney and heart

Filtered blood is sent back to the GI tract via lymphatic vessels (bile ducts)


What is meant by 1st pass metabolism? Why is it important to the fields of pharmacology and drug delivery?

1st pass metabolism refers to Metabolism in the liver of substances (particularly drugs) after they are absorbed via the gastrointestinal track. d

We have to calculate how much drug is needed at the active site, and put enough into the capsule that the amount reaches the target area. Or a different delivery must be used to bypass the GI tract.


Describe 1 technique to engineer a replacement for a failed liver

Decellularizing the liver. Using weak soaps, salts and enzymes, all of the funcitonal parts of the liver are removed. The ECM is left. Blood is added to liver to use all of the formerly active and functioning ECM


Roles of the Liver

-bile salts
-clotting factors
-complement factors
Process Nutrients
Filter Blood


What are the 4 functions of a kidney?

1. Removal of Water soluble waste products and excess water
2 Removal of Urea
3. Respond to ADH and control amount of water in urine. Regulates the volume and composition of extracellular fluid, regulates blood pressure, regulates acid-base balance
4. Production of erythropoietin (blood cell formation) and enzymes


Draw a diagram that shows how glomerular filter works. Label the principle pressures involved in the process



Draw a diagram of the nephron and show where and how reabsorption occurs



How are passive and active transport mechanisms used to reabsorb critical solutes back into the blood?

Passive reabsorption of water uses osmosis, and uses diffusion across concentration gradients

Active transport uses energy driven transport proteins.


What is ADH? How does it help your body to regulate the volume and concentration of extracellular fluids?

ADH is a protein producd by the hypothalamus and is delivered to the kidney via the blood stream.

When ADH is absent, lare volume of water in dilute urine
When ADH is present, small volume of concentrated urine.


How is kidney failure treated and describe one major limitation with this treatment

Interaction of blood with contacting surfaces
Hemolysis of RBC
Activation of complement pathways
adhesion and activation of white blood cells and platelets
increased cancer rates


in the context of this course, what is meant by Mechanics?
Describe four subfields of the study of mechanics (2 from classical, 2 from continuum Mechanics)

Study of the behavior of physical boides when subjected to forces or displacements and the subsequent effect of those bodies on their environement
2 Classical: Statics, Dynamics
2 Continuum: Solid(solid tseformable), Fluid (fluids and solid deformable objects in fluids)

Biomechanics is the study of the structure and function of biological systems by means of the methods of mechanics


Define the term deformation
Describe how plastic deformation is different that elastic deformation

Deformation is the change in shape or size of an object, including fractures.

Plastic- material deforms and remains in the deformed shape even after fore is removed, underlying molecular structure has been changed

Elastic- Material deforms but can still go back to original shape because relative molecular structure is unchanged.


Provide a diagram that shows a typical stress strain curve, label its axis, describe 5 properties that be determined from the curve

X-axis:Strain- dL/L0 Percentage
Y-axis: Stress- pressure induced by a given strain MPa.

-Young's modulus=slope of elastic elongation (stiffness) MPa.
-Yield Strength=elastic/plastic- stress needed to cause plastic deformation
-Ultimate Tensile Strength= max stress on plot MPa
-Total Strain=max strain also called elongation at failure %
-Toughness Area under the curve MPa.


What is the finite element method?
How is it useful to the fields of bioengineering and medicine?

Divides complex differential equations into many simpler relationships/interactions
Total set of relationships/interactions is called a mesh
Each element in the mesh describes the relationship between 2 points or nodes
Many computational software packages are available.

Help provide accurate models. allows better understanding of physiology. Support previously untestable theories. Can be adapted to understand how different diseases and conditions will impact function. Accelerates creation of the innovation of new and improved treatments.


Define what is meant by the term bioisntrumentation

Bioinstrumentation focuses on the development of devices for the study, diagnosis and treatment of disease. Uses knowledge from chem, materials science, optics, acoustics, electronics, measurement principles, mechanics, computation methods


Provide a classification system for the different types of Bioinstrumentation and provide an example of each

1. Bioelectric
-EKG (electro Cardio Gram)
2. Biophysical
-Sphygmomanometer(BP), Ultrasound
3. Biochemical
-Glucometer (diabetes), pregnancy test
4. Biomagnetic
-MRI, MagStim, OctoBot


Describe one instrument that we covered in class

Measures realignments of protons in a magnetic field after exposure to an rf field.
H2O protons are primarily measured.
Can visualize distinct organs and even fine tissue structures due to differences in proton density, temp and chemical state.
Can also use Hemoglobulin as a measurement fMRI or real time MRI


X-ray imaging creates a negative image, explain

Black parts of the x-ray film are totally exposed to the X-rays. The white parts is film not fully exposed to x rays due to dense material preventing the x ray from reaching and exposing the film. Therefore, the image is created by preventing the x-ray to expose the film, thus creating a negative image.


what is the contrast mechanism of x-ray imaging

The amount of x-ray that exposes the film. Created by the density and thickness of material the x-rays are passing through.


how is CT imaging different from traditional Xray?
Describe how the CT imaging system works to create an image

(computer tomography) Created by rotating xray camera, taking many images. Images are stitched together using a computer. Results in 3-D image, with higher resolution


How is ultrasound image generated? what is primary contrast mechanism?

Ultrasound images are generated by oscillationg pressure waves above the limit of human hearing. A crystal turns an electric current into sound waves, the waves are reflected, and the crystals turn the sound waves back into an electric current which produces an image.

Contrast is generated by acoustic impedance.


Describe how ultrasound is being used beyond imaging?

Therapeutic ultrasound is being used for several things.
Localized drug delivery. Designing capsules that burst when hit with a certain frequency of sound wave allow the capsules to pass through the rest of the body, and then to be hit by that frequency at a certain point allowing localized drug delivery.
Localized tumor ablation-cauterization
Activate silicon nanoparticles to fight acne,
massage underlying muslce tissue


How does PET imaging work? describe how gamma rays are generated and detected

Positron Emission Topography
A radio active contrast agent is used. The agent emits positrons. When positrons and electrons interact the annihilate one another and emit gamma rays. The patient is surrounded by gamma ray detectors that solve the physics problem of where the gamma rays originated. This is especially used in cancer imaging. The contrast agent is radioactive glucose. Cancer cells take an more of the glucose than other parts of the body, the PET scan reveals a higher concentration of the glucose in certain areas, leading to a cancer diagnosis.


What is a contrast agent? Why are they used? What concerns exist about them?

Contrast agents are used to enhance the visibility of internal structures. Operate by increasing the contrast causing property of a tissue in a given imaging form. i.e. radio opacity, nuclear relaxation time, sound diffraction etc.

some may be radioactive. almost all remain in the body for longer than it takes to get a successful image.


Proximal Tube

In cortex
Passively reabsorb H20
Passively reabsorb HCO3
Passively Reabsorb K
Actively Reabsorb NaCl
Actively Secrete H+


Descending Loop of Henle

Passively removes H20
Creates concentration Gradient to a passively reabsorb NaCl


Ascending Loop of Henle

Passively removes NaCl in lower part
Actively removes NaCl
No H2O reabsorption


Distal Tube

Passively reasorbs H20
Actively reabsorbs HCO3
Actively Excteres K
Actively excretes H


Collecting Duct

Actively Reabsorb NaCl
Passively reabsorb needed urea
Passively reabsorb H20 if ADH is present


Pressures in Glomerular Filtration

Glomerular hydrostatic pressure (55 mmHG)
Blood colloid osmotic Pressure (-30 mmHG)
Capsular hydrostatic pressure (-15 mm Hg)