BLG111 Quiz 1: Chapters 17 & 18 Flashcards
What are the components of blood?
Blood is a type of connective tissue and a fluid matrix called plasma. It is composed of formed elements suspended in plasma:
- Erythrocytes (red blood cells)
- Leukocytes (white blood cells)
- Platelets
How is bleeding stopped when there is a cut in a blood vessel?
Hemostasis, which requires clotting factors and consists of three steps:
1. Vascular spasm
2. Platelet plug formation
3. Coagulation (blood clotting)
What happens when someone with blood type A+ donates their blood to someone with blood type B-?
Agglutination of the donated blood will occur in the recipient for two reasons:
1. Anti-A antibodies (already present in the recipients blood) will bind to the A antigens of the donor red blood cells and cause agglutination
2. There would also be a delayed production (within 3-5 days) in the recipient of anti-Rh antibodies which will bind to the donor’s Rh antigens (because the donor is Rh+) which will cause more agglutination as well as memory B cell production.
Which of the following blood groups has antibodies that can agglutinate O-blood?
a. Type A+
b. Type B-
c. Type AB+
d. None of the above
None of the above. O blood does not contain A or B antigens and is therefore the universal donor. It also does not contain any Rh.
The universal recipient for blood transfusions is?
AB+. This blood type has both A and B and therefore will not agglutinate. It is also Rh+ and will not attack Rh.
What blood combination would result in hemolytic disease of the newborn?
An Rh- mother with an Rh+ baby
Outline the route blood takes starting at the left atrium and returning to the left atrium.
Oxygen-rich blood is released from the left atrium to the left ventricle, as the mitral valve releases due to pressure. Increased pressure causes the Aortic semilunar valve to open and the blood flows into the body via the systemic circuit. Oxygen-poor blood now returns via the Superior vena cava and Inferior vena cava to the Coronary sinus. It then fills the right atrium. Pressure in the right atrium causes the tricuspid valve to release and blood flows into the right ventricle. Pressure causes the pulmonary semi lunar valve to open and blood flows into the pulmonary trunk where it flows through the pulmonary arteries of the lungs to release CO2 and receive O2. Oxygen rich blood returns to the heart via the four pulmonary veins and is released into the right Atrium. See slide 23 Ch 18.
Explain the conduction system of the heart and the resultant cardiac contraction
- The sinoatrial (SA) node generates impulses (pacemaker)
- The impulses pause (0.1s) at the atrioventricular (AV) node
- The atrioventricular bundle connects the atria to the ventricles
- The bundle branches conduct the impulses through the ventricular septum
- The subendocardial network depolarizes the contractile cells of both ventricles
What is cardiac output?
Stroke volume x Heart rate
The right side of the heart…
a. pumps blood to the lungs
b. pumps blood to the body
c. contains the mitral valve
d. both a and c
a. pumps blood to the lungs
If the bundle branches are surgically removed, what happens?
No more impulses would occur in the Purkinje fibers
“Dup” is?
the second heart sound
What does the P wave show us?
depolarization of the atria
Blood returning to the right side of the heart is?
Deoxygenated
The ECG wave produced during ventricular repolarization is the…?
T wave
What part of the ECG recording occurs at the beginning of ventricular diastole?
T wave
What are the functions of blood?
Transport, regulation, protection
Maintaining normal pH using blood buffers is an example of what function of blood?
Regulation
What is hematocrit?
The percent of blood volume that is RBCs (typically 45%)
What is the Buffy coat?
Consists of white blood cells and platelets (typically 1%)
What is the pH range of the blood?
7.35-7.45
What percentage of body weight does the blood make up?
8%
What is the most abundant plasma protein, making up 60% of plasma? Why is it important?
Albumin is responsible for plasma colloid osmotic pressure - it ensures that fluids stay within the vascular compartment
Which formed element is considered a ‘complete cell’?
White blood cell. RBCs have no nuclei or other organelles, platelets are cell fragments.
What three features make RBCs efficient for gas transport?
- Biconcave shape offers huge surface area relative to volume for gas exchange
- Hemoglobin makes up 97% of cell volume (binds reversibly with oxygen)
- No mitochondria; ATP production is anaerobic - they do not consume oxygen, just transport
What are normal levels of hemoglobin?
14-16g/100mL
The formation of all blood cells is a process called…?
Hematopoiesis