Test 3 Review

venous

deoxygenated

arterial

oxygenated

blood flows down pressure gradient

highest pressure in aorta, lowest in vena cava

flow

* if pressures on both sides are same, no movement
* flow through tube depends on pressure gradient
* difference in pressure is important not amount of pressure
* increase as pressure gradient increases or as resistance decreases

resistance

opposes flow

inversely proportional to flow (flow decreases as resistance increases)

proportional to length of tube (resistance increases as length increases)

proportional to viscosity (resistance increases as viscosity increases)

inversely proportional to tube radius to fourth power (as radius increases, resistance decreases)

autorhythmic cells (pacemaker)

signal for contraction; smaller and fewer contractile fibers compared to contractile cells; do not have organized sarcomere

make it so heart can contract without being attached to body

contractile cells

striated fibers organized into sarcomeres

cardiac vs. skeletal muscle

smaller and single nucleus per fiber

branch and join neighboring cells through intercalated disks

gap junctions

T-tubules are larger and branch

sarcoplasmic reticulum is smaller

mitochondria occupy 1/3 of cell volume

want cardiac to be aerobic

cardiac output

stroke volume x heart rate

stroke volume

EDV-ESV

heart rate

EKG (300/\# of big boxes)

cardiovascular disease

LDL tries to fill vessels with junk (too much clot/plaques)

HDL tries to clean it up

white blood cells

nucleus to divide

last hours to days

platelets

thrombopoietin produced

last 10 days

red blood cells

erythropoietin produced (controlled by oxygen levels)

last 100 days

relation to atmospheric pressure

breathing in (negative)

breathing out (positive)

intrapleural (negative)

compliance

ability to stretch

highly compliant is good

problem=restrictive lung disease

elastance

ability to bounce back to normal size

Law of LaPlace

surfactant decreases surface tension

pressure greater in a smaller bubble without surfactant

surfactant makes size not matter

obstructive lung disease

FEV1/FVC= less than 0.7

restrictive lung disease

reduced lung compliance

FEV1/FVC= more than 0.7

diffusion

goes along concentration gradient

problems cause hypoxia

innervation of respiratory muscles

somatic motor neurons

cardiac muscle contraction force

can be graded

force generated proportional to number of active cross-bridges (determined by how much calcium is bound to troponin)

sarcomere length affects force of contraction

how electrical activity goes through heart

SA node to internodal pathway (atrium) to AV node (holds to allow atria to contract) to AV bundles to branches to Purkinje fibers (electrical activity spreads to contractile tissue and start contraction of ventricle

electrical activity before mechanical activity

P wave

no mechanical activity

as it ends, atria depolarizes

QRS interval

contracts as you go though (ventricle) (first heart sound)

semilunar valves close (2nd heart sound) as ventricles repolarize

decrease heart rate

parasympathetic

increase heart rate

sympathetic

fenestrated capillaries

kidneys and intestines

positive inotropes

increased contractility

epinephrine, norepinephrine, digitalis

MAP factors

blood volume, effectiveness of the heart as a pump (CO), resistance of system to blood flow, relative distribution of blood between arterial and venous blood vessels

active hyperemia

normal metabolic

reactive hyperemia

pathologial

blood vessels

under sympathetic innervation

contraction/relaxation cycle

need electrical current, cause calcium to come from ECF and SR, number of calcium determines force of contraction, calcium interacts with actin and myosin

relaxation: calcium goes into SR and sodium calcium exchange (NCX), sodium pumped into cell and calcium pumped out (no ATP used)

reset gradient with ATP

contractile action potential

plateau phase makes it so it can’t depolarize to allow heart to fully have atria contract (refractory period)

potassium leaves cell and calcium enters cell (positives going both directions creates plateau)

pacemaker action potential

no resting potential (unstable)

sodium in, calcium pushes to threshold, more calcium channels open, calcium channels close, potassium channels open to repolarize

capillaries

large cross-sectional area so low velocity

allows time for exchange with tissues

veins

volume reservoir

arteries

pressure reservoir

shunting blood

shunt down different routes by squeezing/constricting down arteries where blood isn't needed

stroke volume factors

contractility, EDV, length-tension relationship (ESV)

inotropic agent

chemical that affects contractility

negative inotropes

decrease contractility

myogenic autoregulation

adjusts blood flow

vascular smooth muscle regulates own state of contraction

contracts to protect itself from stretching

baroreceptor reflex

increased blood pressure: increased parasympathetic and decreased sympathetic lead to decreased blood pressure

net filtration

increased hydrostatic pressure on arterial

net absorption

higher oncotic pressure than hydrostatic

hemoglobin

plays a role in oxygen transport

attaches to four binding sites: 2 alpha, 2 beta

platelet plug

exposed collagen binds and activates platelets, release of platelet factors, factors attract more platelets, platelets aggregate into platelet plug

coagulation cascade

intrinsic (12) pathway and extrinsic (3) pathway lead to common pathway (10) activates thrombin, activates fibrin which creates clot to fibrinolysis which gets rid of fibrin after repair so vessel returns to normal

respiratory system functions

exchange of gases between atmosphere and blood

homeostatic regulation of body pH

protection from inhaled pathogens and irritating substances

vocalization

respiratory system bulk flow

flow takes place from regions of higher to lower pressure

muscular pump creates pressure gradients

resistance to air flow is influenced primarily by diameter of tubes

muscles of inspiration

sternocleidomastoid, external intercostals, scalenes, diaphragm

muscles of expiration

internal intercostals and abdominal muscles

Type 1 alveolar cell

gas exchange

type 2 alveolar cell

synthesizes surfactant

Boyle's Law

inverse relationship between pressure and volume

tidal volume

normal expiration

expiratory reserve volume

Amount of air that can be forcefully exhaled

inspiratory reserve volume

amount of air that can be forcefully inhaled

residual volume

Amount of air remaining in the lungs after a forced exhalation

inspiratory capacity

tidal volume + inspiratory reserve volume

vital capacity

tidal volume + inspiratory reserve volume + expiratory reserve volume

total lung capacity

tidal volume + inspiratory reserve volume + expiratory reserve volume + residual volume

functional residual capacity

expiratory reserve volume + residual volume

inspiration

thoracic volume increases

expiration

diaphragm relaxes, thoracic volume decreases

bronchoconstriction

increases resistance (parasympathetic)

bronchodilation

decreased resistance (sympathetic)

eupnea

normal breathing

hyperpnea

increased respiratory rate and/or volume in response to increased metabolism (exercise)

hyperventilation

increased respiratory rate and/or volume without increased metabolism (emotional/blowing balloon)

hypoventilation

decreased alveolar ventilation (shallow breathing)

tachypnea

increased respiratory rate with decreased depth (panting); rapid breathing

dyspnea

difficulty breathing (air hunger) (pathologies or hard exercise)

apnea

cessation of breathing (breath-holding; depression of CNS)

emphysema

destruction of alveoli means less surface area for gas exchange

obstructive

decreased surface area

fibrotic lung disease

thickened alveolar membrane slows gas exchange; loss of lung compliance

more tissue, harder to exchange

pulmonary edema

fluid in interstitial space increases diffusion distance

increased extra fluid, hard to exchange

asthma

increased airway resistance decreased alveolar ventilation

oxygen transport

alveoli diffuse oxygen into blood; oxygen dissolved in plasma but majority attach to red blood cells; transport in blood; oxygen diffuses into tissue cells and used for cellular respiration

factors affecting hemoglobin's oxygen affinity

pH, temperature, carbon dioxide, 2,3-BPG

protective pulmonary reflexes

respond to injury or irritation

bronchoconstriction, sneezing, coughing, Hering-Breuer inflation reflex

carbon dioxide transport

mostly as bicarbonate

The integrating center for neural control of blood pressure resides in the

medulla oblongata

A downward deflection on an ECG can represent

depolarization and net current movement toward the negative electrode

The flattening of the action potentials of mycardial contractile cells, called the plateau phase, is due to a combination of \__________ K+ permeability and \___________ Ca2+ permeability.

decreasing, increasing

Compared to skeletal muscle, the action potential of cardiac cells is

longer

Due to the differences in opposing forces, there is net \__________ occuring at the arteriolar end of most capillaries coupled with net \_________ at the venous end.

filtration, absorption

The lymphatic system

does not have its own pump like the heart, relies on skeletal muscle pump to circulate lymph fluid, empties the lymph vessels into the veins near the clavicles, has lymph nodes positioned strategically where immunologically active cells interact with the lymph

The sympathetic neurons have decreased to a new steady-state firing rate, blood vessels are said to be vasodilated. This is an example of \________ control.

tonic

The purpose of having valves in the cardiovascular system is to

ensure that blood flows in the correct direction

The AV node is important because it

directs electrical impulses from the atria to the ventricles & delays the transmission of the electrical impulses to the ventricles in order for the atria to finish contracting.

The first heart sound is heard when

the AV valves close

The total volume of blood in the body of a 70kg man is approximately

5-6 liters

During the isovolumic phase of ventricular systole,

the atrioventricular valves and semilunar valves are closed

Catecholamines such as norepinephrine increase the pacemaker potential of cardiac autorhythmic cells by binding to \_____________ receptors.

beta 1 adrenergic

The first steps in hemostasis involve \__________ and \____________

vasoconstriction, platelet plug formation

When baroreceptors sense a loss of blood pressure, they \_________ their firing rate

decrease