Cardiac output
What is the equation for Cardiac Output?
Cardiac Output = Stroke volume x Heart rate
During exercise
- Name an organ we increase blood flow to
- Name an organ we don't change blood flow to
- Name an organ we decrease blood flow to
Increase blood flow to: heart, muscular, coronary, cutaneous
No change: brain
Decrease blood flow: digestive, renal
The phrase "more in, more out" is from which mechanism?
Frank-Starling Law
What is the difference between flow and velocity of blood? Explain by comparing between different vessel types.
Flow: same amount for all vessels
Velocity: speed at which the blood travels; faster in the aorta compared to the capillaries
What are the two layers of the lungs and the space in between called?
Deepest layer: visceral pleura
Space in between: pleural cavity
Superficial layer: Parietal layer
We open _________ in capillaries when blood flow increases.
We open sphincters in capillaries when blood flow increases.
Norepinephrine is released via sympathetic activation to increase permeability to Na+ and Ca++. What affect does this have on heart rate? (Hint: think of the intrinsic conduction system action potentials)
Norepinephrine (sympathetic): increased permeability to Na+ and Ca++
- Allows for a lower repolarization and hyperpolarization period and faster depolarization periods to increase heart rate
Which mechanism controls stroke volume and which controls heart rate?
Frank-starling: stroke volume
Bainbridge: heart rate
What is the short term blood pressure control?
Neural control --> vasoconstriction/vasodilation
What is the muscle tthat moves inferiorly during ventilation? Is it skeletal or smooth muscle?
Diaphragm; skeletal muscle
List arteries, capillaries, and veins in order from most/highest to least/lowest for the following:
1. Cross-sectional area
2. Average blood pressure
1. Cross-sectional area: capillaries --> veins --> arteries
2. Average blood pressure: arteries --> veins --> capillaries
Ach is released via parasympathetic activation to increase permeability to k+. What affect does this have on heart rate? (Hint: think of the intrinsic conduction system action potentials)
Ach (parasympathetic): increases permeability to K+
- Allows for slower heart rates since the hyperpolarization period will increase
Fill in the blanks:
The more the cardiac muscle cells _____ , the more forcefully they ______.
The more the cardiac muscle cells stretch, the more forcefully they contract.
Describe the effect of increased ANP (atrial natriuretic peptide).
ANP makes you pee!
Increased ANP will decrease blood pressure by releasing extracellular fluid volume.
What is pulmonary ventilation?
Pumping air in/out of lungs
Increased preload via ______-_______ increases ___-______ volume.
Increased preload via Frank-Starling Law increases end-diastolic volume.
Give a definition of myogenic control and a tissue that relies on this mechanism.
Vascular smooth muscles respond to sudden pressure shifts with changes in tone in order to maintain constant flow.
Brain!
Fill in the blank:
Both mechanisms respond to _____.
Both mechanisms respond to increased venous return.
What is the direct effect of increased angiotensin II? When/why is it released?
Angiotensin II functions to vasoconstrict the vessels when blood pressure is low due to a decrease in blood volume.
Describe the difference between external ventilation and internal ventilation.
External ventilation: gas exchange at blood-gas barrier in lung
Internal ventilation: gas exchange at tissues
What will happen to cardiac output if an individual begins exercising? Describe both factors and how they will be affected.
Heart rate will increase.
Stroke volume will increase (more blood will be ejected).
This combination allows for increased O2 delivery to the tissues.
Give a definition of metabolic control and main stimuli that triggers this mechanism.
Give your tissues what they need when they need it. Nutritional status of tissues regulate capillary blood flow ~ low 02 is the strongest stimuli
Fill in the blank regarding Bainbridge reflex:
Receptors in ____ ____ detect increased volume. Through __________ activation of the SA node, _____ ____ is increase.
Receptors in right atrium detect increased volume. Through sympathetic activation of the SA node, heart rate is increase.
Name three hormones that cause vasoconstriction to increase blood pressure.
ADH, epinephrine, norepinephrine, angiotensin II
Name at least two of the three main functions of the pleural cavity and layers of the lungs.
1. Lubrication for reduction of friction
2. Compartmentalization
3. Creates pressure gradient