2275 lab 2

QRS complex

= (Height of the R wave) - (Height of the Q wave) - (Height of the S wave) An abnormal mean QRS axis could indicate changes in the sequence of ventricular activation or myocardial damage.

tunica externa

Also known as the tunica adventitia. Medium veins have a very thick tunica adventitia that is typically at least twice as thick as the tunica media.

arteriole

Arterioles have a thin tunica intima, 2-3 layers of smooth muscle in the tunica media, and a thin tunica adventitia (tunica externa).

List three different potential symptoms of reduced blood flow out of the kidney.

Blood flow in the kidney begins to pool. This can cause pain, blood in uterine, significant weight loss, nausea, and vericose veins (veins that swell when blood pools instead of flowing normally)

capillary

Capillaries consist only of a single layer of endothelial cells and some nearby supporting cells called pericytes. 1600x magnification

atherosclerotic plaque

Damage to the endothelium lining a blood vessel leads to the adhesion of cholesterol to the underlying subendothelial layer. In response to this, white blood cells (monocytes and macrophages) move into the wall of the vessel to remove the cholesterol. The buildup of cholesterol and white blood cells is referred to as plaque, and is the early sign of a disease called atherosclerosis. This accumulation of fatty streaks within the blood vessel wall eventually leads to narrowing of the lumen.

AV node

Electrical connection between atrial muscle and ventricular muscle, also serves as backup pacemaker.

heart rate equation

HR = 60 ÷ t , where HR = Heart Rate (beats/min) and, t = time interval (seconds).

electrodes in Einthoven's triangle

Lead 1- right arm, negative electrodeLead 2- right arm -> left leg (positive electrode)Lead 3- left arm (negative) --> left leg (inactive - serves to ensure quality of signal

tunica intima

Medium veins have a relatively thin tunica intima and an indistinct internal elastic lamina (IEL).

Which of the following does NOT branch off the celiac trunk? Common hepatic artery Left gastric artery Proper hepatic artery Splenic artery

Proper hepatic artery

Describe relationships between ECG and finger pulse trace.

The electrical activity in the heart always precedes the mechanical contraction. Hence, there will be a significant delay between the ECG and pulse measured in the ascending aorta. This delay or "lag" is increased here as were are measuring the pulse in the finger; the pulse wave takes a finite time to travel that distance

SA node

The first wave of electrical signaling in a heart beat is initiated by a group of pacemaker cells at the top of the heart Because heart muscle cells permit "spread" of electrical charge to adjacent muscle cells, this initial wave travels across the wall of the atrium from the SA node to atrioventricular, or AV, node

Use the CT image to compare the left renal vein to the right renal vein. What do you notice? Justify any differences.

The left renal vein is longer because the inferior vena cava is situated more to the right side of the body's midline. In this specific CT sane, the diameter of the left renal vein is larger as well.

microvasculature

The microvasculature of the body is composed of arterioles, capillaries, and venules. All three of these vessel types contain little or no smooth muscle and have a limited amount of elastic fibers in their walls.

Why is the right renal artery longer than the left renal artery?

The right renal artery is longer than the left renal artery because the inferior vena cava is situated to the right of the abdominal aorta. Therefore, the right renal artery has to cross behind the inferior vena cava to get to the right kidney, whereas left renal artery is closer to the left kidney.

tunica madia

The tunica media of medium veins consists of 3-5 layers of smooth muscle cells and an indistinct external elastic lamina (EEL).

tunica

The walls of both arteries and veins have three layers These tunica include the tunica intima, the tunica media, and the tunica externa. The innermost layer is the tunica intima, and is composed of an endothelium and a sub- endothelial layer that is made up of a thin, areolar connective tissue. The tunica media is the middle layer, which is composed of circularly-arranged smooth muscles. Vasoconstriction is achieved by contracting this layer. The tunica externa is the outermost layer, and is composed of areolar connective tissue that contains elastic and collagen fivers. This layer helps anchor the vessel to other structures.

venule

Venules have a thin tunica intima, a thin tunica media, and little to no tunica adventitia (tunica externa).

how do veins in the leg move blood against the force of gravity?

When the muscles in your leg contract they squeeze against the veins, forcing the blood through the vessels. When your muscles relax there are unidirectional valves within your veins that prevent the blood from flowing back down. This is why its important to get up and stretch or walk after sitting down for long periods of time

anastomosis

a network or a connection between multiple blood vessels. The network functions to ensure a continuous blood supply to tissue if one vessel is blocked due to normal movements of the body or injury, disease, or surgery. The network also means that blood can flow in both directions within these vessels.

negatie vs. positive vector

a positive vector (positive current):-when positive charges moves from negative to positive (creates positive deflection) or negative charges move from positive to negative (creates negative delfection/current)*ex: positive current = moving from right hand (negative) to lead in left hand (positive) a negative vector (negative current):-when positive charges move from + to - or negative charges move from - to +

When a depolarization wave (which is a positive wave) is moving from the SA node to the AV node, what is detected on lead I?

a positive wave moving from the negative electrode to the positive electrode, generating an upward deflection in the trace.

azygos vein

a vein running up the right side of the thoracic vertebral column draining itself towards the superior vena cava.

action potential vs ECG

action potential is one electrical event recorded from a single cell, often intracellularly; the ECG is an extracellular recording that represents the sum of multiple action potentials taking place in many heart muscle cells.

Trace the flow of blood from the aortic arch to the right atrium passing through a capillary bed in the right deep palm.

aortic arch brachiocephalic trunk right subclavian artery right axillary artery right brachial artery right ulnar artery deep palmar arterial arch capillary bed deep palmar venous arch right ulnar vein right basilic vein right axillary vein right axillary vein right subclavian vein right brachiocephalic vein

P wave

atrial depolarization and is associated with atrial contraction.

venules

collect blood from capillary beds and return blood to the heart using the venous network.

The internal carotid artery and external carotid artery branch off the

common carotid artery.

the inferior vena cava is formed by the union of

common illiac veins

brachial artery

continuation of the axillary artery and travels distally along the medial aspect of the arm where it terminates at the cubital fossa.

the abdominal aorta

distal part of the descending aorta. It contains three important arterial branches (i.e., celiac trunk, superior mesenteric artery, and inferior mesenteric artery) that provide blood to all the organs within the abdominal cavity

Which component in the wall of the aorta is responsible for withstanding high blood pressures due to ejection of blood from the heart?

elastic fibers

the facial artery branches off the

external carotid artery

What artery provides the main blood supply to the anterior thigh?

femoral artery

capillaries

fine-branching blood vessels where nutrient and waste product exchange between blood and tissue takes place. Capillaries form a network between the arterioles and venules.

Einthoven's triangle

hypothetical triangle around the heart to describe the recorded electrical activity when electrodes are placed at the distal ends of a human body - normally both arms and the left leg as shown here (Fig. 1). The sides of the triangle are numbered to correspond with the three pairs of electrodes used for a recording, each pair of electrodes is called a lead. in lead I the left arm electrode is designated as positive and the right arm electrode is designated as negative. If you only record lead I, you do not need to attach the electrode to the left leg. However, we DO connect a third electrode to the right leg (Fig. 2). This electrode is inactive and serves as a reference to ground we use multiple leads to assess the hearts function

what would cause smaller veins under the skin to buldge?

if the unidirectional valved degrade or fail, blood will flow back down into the veins instead of to the heart. Increased blood in the veins causes them to buldge and appear blue

arterioles

important for maintaining steady blood pressure due to their vastness and their ability to vasoconstrict and vasodilate. This ability controls which capillary beds blood is directed toward.

what is the largest vein in the body?

inferior vena cava It travels superiorly along the right side of the abdominal aorta and is anterior to the vertebral column

systemic circulation

is a closed-loop circuit between the heart and all the tissues of the body. It transports oxygenated blood from the left ventricle of the heart to capillaries within tissues for gas exchange. includes all the arteries and arterioles that transport oxygenated blood from the heart to the tissues. It also includes the veins and venules that transport deoxygenated blood from the tissues back to the heart.

pulmonary circulation

is a closed-loop circuit between the heart and the lungs. It transports deoxygenated blood from the right ventricle of the heart to capillaries within the lung for gas exchange. transports deoxygenated blood from the right ventricle to the lungs where the gas exchange occurs (carbon dioxide is exchanged for oxygen).

myocardial ishemia

lack of oxygen to the myocardium ischemic changes in the form of inverted T wave; ST segment appears to be depressed relative to isometric line

Atherosclerosis

large deposition of lipid or other debris on the inside dangerous, and may contribute to many pathological conditions

basilic vein

large superficial vein of the upper limb that helps drain parts of the hand and forearm

the abdominal aorta supplies blood to _________________. IT branches off to become

many organs located in the abdominal cavity; common iliac arteries

cephalic vein

other main vein of the arm. Together with basilic vein, they empty into the axillary vein.

The arteries in the systemic circulation transport ________________ blood while the arteries in the pulmonary circulation carry _________________ blood.

oxygenated deoxygenated

When a positive charge moves from the right hand to the left hand, what will be recorded in Lead I? 1 / 1

positive current

When a positive charge moves from the right hand to the left hand, what will be recorded in Lead I?

positive current (depolarization is a positive wave from SA node to AV node.)

What would happen if the left renal vein is pinched between the aorta and the superior mesentric artery?

reduced blood flow out of the kidney

Which component in the medium artery wall allows the artery to control the diameter of the lumen via vasoconstriction and vasodilation?

smooth muscle cells

the axillary artery is a continuation of the

subclavian artery. this name change occurs after the subclavian artery passes the lateral border of the first rib supplies blood to the lateral aspect of the thorax, axilla (armpit), and upper limb.

Why is the left brachiocephalic vein longer than the right brachiocephalic vein?

the left brachiocephalic vein needs to cross the midline of the body to meet the right brachiocephalic vein. Together, these large veins form the superior vena cava, which is situated to the right side of the posterior heart

Why do you suppose the shoulder and knee joints have multiple anastomoses?

the shoulder and knee joints have a large range of motion. naturally occurring anastomoses allow blood to flow around the joint no matter what movement is being performed.

compare and contrast the common carotid arteries and subclavian arteries for each side of the body. What is the significance of the brachiocephalic trunk (artery)?

there is only one brachiocephalic trunk originating directly from the aortic arch. It terminates as it bifurcates into the right common carotid artery and right subclavian artery. The left side of the body does not have its own brachiocephalic trunk. Instead, the left common carotid artery and left subclavian artery are direct branches of the aortic arch.

The common carotid artery and internal jugular vein pump blood...

to and from the brain, neck, and face

QRS complex

ventricular depolarization but also contains atrial repolarization.

T wave

ventricular repolarization and initiates ventricular relaxation

common iliac arteries

which supply blood to the hip and lower limbs