In the large arteries, what is the function of the tunica media?
Large elastic muscular fibers. High pressure pipes with elastic recoil.
What is the function of the arterioles?
Very small muscular arteries that regulate the blood flow to various organs.
What is the function of the capillaries?
Very thin walled vessels that allow for the exchange of nutrients and wastes.
Name and describe the 3 types of capillaries
-Continuous: most common, least permeable
-Fenestrated: highly permeable, rapid filtration and absorption. (Kidneys, sm. Intestine)
-Sinusoidal: Biggest spaces, most so big that proteins can move through. (Liver, spleen, red bone marrow)
Compare veins with arteries
Layers: Same 3 layers as arteries
Walls: Thin and lumen is large
Valves: Paired (shirt pocket valves), to prevent back flow.
Numbers: Many more than arteries
Location: Both deep and superficial
Blood volume: 65% total blood volume is in the veins
Vascular compliance: High compliance, ability to stretch keeps pressure low.
What percentages are the distribution of blood?
Arteries and Arterioles: 15%
Capillaries: 5%
Veins and Venules: 65%
Heart and Lungs: 15%
As blood flows into a larger area, the rate of flow ___________.
Slows through capillaries.
The type of vessel with the largest cross-sectional area and therefore the slowest blood flow is the _____________.
Capillary
In which vessel is the slowest pressure found?
Veins
Define peripheral resistance.
The opposition to blood flow.
Define Cardiac output.
The flow out of a ventricle of the heart per minute.
CO= SV x HR
Write an equation to describe the relationship between cardiac output, stroke volume, and heart rate.
CO= SV x HR
The major force that pushes ISF from the capillaries is _________.
Blood Pressure
The major force allowing ISF to be reabsorbed is __________.
Osmosis
The remaining ISF within the tissues after osmosis enter the _________________.
Lymph Capillaries
List 2 basic causes of Edema.
Capillary blood pressure too high.
Blood colloid osmotic pressure (BCOP) too low.
Describe how a decrease of plasma proteins may cause edema.
Because there is less fluid being returned to the capillary.
Decrease in BCOP = Increased edema
If venous return decreases, then cardiac output _______.
Decreases
Venous pressure stays the same throughout the day.
False
Blood flow is proportional to need in most tissues.
True
Define autoregulation
The regulation of blood flow without the nerves or hormones.
Explain the role of the precapillary sphincter.
Smooth muscle band that contracts when there is an ample supply of oxygen to the capillaries.
Oxygen increase in the tissue will cause the precapillary sphincter to close, thereby increasing the blood flow to the tissues.
False
Define vasomotor tone.
The partial contraction of the arterioles and veins.
Where are vasoconstrictor fibers found?
All vessels, but most important in the nonvital organs.
What neurotransmitter is associated with the vasoconstrictor fibers?
Norepinephrine (NE)
The effect of widespread vasoconstriction on nonvital organs causes a ___________ in the blood flow to these organs.
Decrease
When there is an increase in vasoconstriction, one would expect an ____________ in peripheral resistance and a ____________ in blood pressure.
Increase, Increase
If cardiac output decreases, mean arterial pressure will____________.
Decrease
If vessel diameter decreases, peripheral resistence will ____________.
Increase
Increased viscosity of the blood will ___________ peripheral resistance.
Increase
The baroreceptor reflex controls BP by monitoring receptors found in the _____________. A decrease in parasympathetic stimulation of the heart causes an _____________ in peripheral resistance and therefore an _________ in BP.
Neck and aorta, Increase, Increase
List 2 adrenal medullary hormones and their effect on BP.
Norepinephrine and Epinephrine.
Increase BP (sympathetic stimulation)
Explain the chemoreceptor reflex.
Decreased O2 and Increased CO2 cause a decrease in pH, the central chemoreceptors react by increasing SV, HR, and vasoconstriction= Increase in BP. Chemoreceptors monitor O2 and CO2.
List 2 hormones that increase BP.
Aldosterone and ADH
Name a hormone that decreases BP.
ANH
Explain the fluid shift mechanism of BP regulation.
An increase in BP= an increase in ISF----> Decrease BV, Decrease BP
Describe Artherosclerosis and it's effect on BP.
Calcium and cholesterol deposits in Tunica media, which increase the PR=increase in BP=increase the workload on the heart and decrease the blood flow to the tissues.
List possible causes of circulatory shock.
Circulatory shock is inadequate CO. Cause could be hemmorhage or massive allergic reaction.
Aldosterone
Source: Adrenal cortex
Stimulus: Decrease in NA+ or a decrease on BV.
Effect: Cause kidneys to retain salt and water--> decrease the production of urine--> Increase in BV, Increase in VR, Increase CO, Increase BP.
Vasopressin (ADH)
Source: Posterior pituitary
Stimulus: Dehydration
Effects: Cause the kidneys to retain water--> Increase BV, Increase BP, and also casue vasoconstriction which increase BP.
Atrial Natriuretic Hormone (ANH)
Source: Atria of the heart
Stimulus: Increase VR.
Effect: Causes kidneys to excrete salt and water--> Decrease BV, decrease VR, decrease CO, decrease BP.
List the 6 major classes of Nutrients
Carbohydrates
Lipids
Proteins
Water
Minerals >micronutrient
Vitamins> micronutrient
What are the functions of carbohydrates?
They are an energy source. There are 3 classes of Carbohydrates.
Monosaccharides: Glucose, Fructose, Galactose
Disaccharides: Double sugars
Sucrose: (glucose+fructose)
Maltose: (glucose+glucose)
Lactose: (glucose+galactose)
Polysaccharides: Complex carbohydrates
Starch
Glycogen
Cellulose
List the functions of triglycerides
They are an important source of ATP. Components are 3 fatty acids and a glycerol.
Functions are cell membrane fluidity, energy storage, and insulation.
List the functions of cholesterol.
Are used to synthesize the sex hormones and Aldosterone (control BP).
List the functions of phospholipids
They are 2 fatty acids bound with phosphorous.
Functions are to form the phospholipid bilayer of the cell membrane.
List the functions of the essential fatty acids.
Linoleic acid (omega 6)
Linolenic acid (omega 3)
Functions are cell membrane fluidity and synthesize prostoglandins for blood clotting.
What does essential refer to? Nonessential?
Essential means that it must be obtained in the diet. Nonessential means that the body can syntesize it.
Define complete protein. List examples.
Milk, meat, eggs, grains and bean. Foods which contain all essential amino acids.
Define Vitamin.
Large complex organic molecules needed by body cells but not synthesized by cells, obtainable only by other living things.
With O2, Acetyl-CoA formation--> 3 Carbons loses a CO2 and energy rich H's--> Acetyl, which is carried by CoA--> Acetyl CoA+ CO2+ 2 H which enters the Krebs cycle
What are the products of Glycolysis?
2 Pyruvic Acids and H's--> 2 Lactic Acids= 2 ATP
Where in the cell is Acetyl CoA formation?
The Mitochondria
Where does the Krebs cycle occur?
The Mitochondria
What are the two phases of anaerbic respiration?
Glycolysis and Lactic Acid Formation
What is the total amount of ATP that is produced from a single glucose molecule?
38 ATP
What is the total amount of ATP from Glycolysis?
2 ATP
What is the total amount of ATP from the Krebs cycle?
2 ATP
Amount of ATP from the Electron Transport Chain?
34 ATP
Write the chemical equation that represents the oxidation of glucose.
C6 H12 O6 + O2= 6CO2 + 6H2O
Define absorptive state.
Food digestion
What is the hormonal control for the absorptive state?
Insulin
Glucose is the body's preferred fuel. What happens when fructose and galactose are ingested?
Converted to glucose by liver through facilitated diffusion. Requires carrier.
Define Glycogenesis. What is it's function?
The making of glycogen from glucose. Stores glucose for later.
Describe the differences in VLDL's/LDL's and HDL's.
VLDL's/LDL's= Bad cholesterol (stores)
HDL's= Good cholesterol (gets rid of)
Define Lipogenesis. Where in the body does this occur?
Making Lipids. In the liver and adipocytes.
3 Fatty acids + glycerol--> Triglyceride
Define Transamination
Transferring one amino acid into a ketoacid to synthesize nonessential amino acids.
Why is ammonia converted to Urea? Where in the body does this occur?
Urea=Lower toxicity than ammonia. Occurs in the liver.
Blood glucose levels must be maintained at what?
70-110 mg per milliliter
What is the first source of blood glucose during the post-absorptive state?
Glycogenolysis
Define Gluconeogenesis.
Glucose synthesis from amino acids, lactic acid, or glycerol to increase blood glucose. The liver transforms glycerol to glucose which then enters the Krebs cycle and produces ATP.
Define Ketogenesis
Liver transforms acetyls from fats into ketone bodies (fat catabolism).
List the phases of starvation
Fat Metabolism
Brain uses ketone bodies
Catabolism of body proteins
List the hormones involved with the postabsorptive state and their influence on blood glucose.
Glucagon- Increases blood glucose
Epinephrine and Norepinephrine- Increases blood glucose
Cortisol- Increases blood glucose
Growth hormone- Increases blood glucose
During exercise, hormones are in the _____________ and glucose levels ________.
postabsorptive state, increase
Define Hypoglycemia and the symptoms relating to brain function.
Low blood glucose. Symptoms are fatigue, lack of concentration, etc.
Insulin dependent diabetes
Insulin levels: Low
Cause: Pancreas not producing enough insulin
Occurs: In youth
Type 1
Non-Insulin dependent diabetes
Insulin levels: Normal
Causes: Tissues have lost ability to respond to Insulin.
Occurs: In adults
Type 2
97%
List 4 symptoms of diabetes
Elevated blood glucose
Glucosuria
Polyuria
Thirst
Define Basal Metabolic Rate
The bodys total energy use during
1. Awake
2. Resting
3. Postabsorptive
4. Thermoneutral
How does fever effect BMR?
Increases BMR
How does regular exercise effect BMR?
Increases BMR
List 4 foods and their caloric value.
Lipids 9
Protein 4
Carbs 4
Alcohol 7
Define radiation.
Heat transfer from body to air.
Define Conduction
Heat transfer from body to an object.
Explain why one feels hotter when the heat index is high.
An increase in humidity= a decrease in evaporation rate
What is the body's long term adjustment to a high environmental temp?
BMR decreases because of a decrease in thyroid hormone and epinephrine.
Define fever and explain its function.
Body temp increases beyond the norm= an increase in chemical reactions to help fight infection.
What is the function of the nephron?
Remove waste from blood and produce urine.
1.3 million
Types: Cortical (short) loops of henle (85%)
Juxtamedullary (long) loops of henle (15%)
Define Renal fraction.
1 L/min- blood flow to the kidney
5 L/min- blood flow to heart
List the normal constituents of urine.
Water
NaCL
Urea
Metabolites
List the average pH and volume of urine.
Average pH is 6, normal anywhere from 5-8
Volume- 1L/per 24 hours
List 4 abnormal constituents of Urine. What is the diagnostic significance of each?
Glucose=Diabetes
Albumin=Kidney malfunction
RBC's=Infection, kidney stone, kidney damage
Ketone bodies= from excess fat catabolism--> overdieting
List the 4 steps involved in the formation of urine from plasma.
1. Glomerular filtration
2. Tubular reabsorption of water and nutrients
3. Tubular secretion of specific solutes
4. Adjustment of water volume
Glomerular filtration occurs primarily in the ____________ and produces filtrate which enters into the ________________.
Glomerulus, Proximal Tubule
What is the Glomerular Filtration Rate? How does this value relate to the amount of urine produced per day?
The amount of filtrate produced per minute.
125ml/min
180L/day
The Glomelular filtration rate is high because of the __________ permeability of the filtration membrane and the ________ glomerular capillary pressure (______mm Hg).
High, High, 50
If GFR increases, GCP _________.
Increases
Hypotension ____ GCP.
Decreases
Increases BV _______ GCP.
Increases
List 2 factors opposing glomerular filtration.
Capsular pressure
Colloid osmotic pressure of glomerular blood.
Write the equation to describe the relationship between filtration pressure, Glomerular capillary pressure, capsular pressure and colloid osmotic pressure. Then find the filtration pressure.
Adult-Sacral parasymp. neurons stimulated--> Cerebral cortex stimulated, then adult decides if it is right time and place--> Relaxation of Internal and External urethral sphincters--> Urination
