Anatomy and Physiology 2- Test 1 Flashcards
Explain in general terms the production of all formed elements:
Hematopoiesis is the process of BC formation.
hematopoietic stem cells that go through a combination of divisions, you end up with all different formed elements.
What is blood made up of & what is the function of blood?
Blood is made up of plasma (90% water & 10% solutes), & formed elements. RBCs, WBCs, Platelets.
- RBCs are the most abundent of the formed elements
- Blood functions to transport materials & heat throughout the body. It flows in response to a pressure gradiant.
What is the function of RBCs, WBCs and & Platelets?
RBCs play a critical role is the transport of oxygen.
WBCs function is immunity
Platelets function is clotting.
Describe the clotting process & explain why clots are red?
Step 1: plateletes clump at the site of the punctured vessel & partially seal the hole.
Step 2: proteins are produced which form long threads of fibrin
Step 3: fibrin threads wind around the clump of platelets completing the seal
*Trapped RBCs give clot their red color. The clot is destroyed as the vessel wall is being repaired.
Describe Atria & Ventricle
- The atria are known as receiving chamber because they receive blood from the veins.
- The ventricles are known as pumping chambers because they push blood out of the heart.
Describe Myocardium.
The myocardium is the thick, contractile middle layer of the heart wall. It is the muscle of the heart.
*It forcefully compresses the heart cavities, & the blood within the heart.
Distinguish the difference between the two chambers of the heart:
The Atria are the top two & they receive blood from the veins.
The Ventricles are the pumping chamberrs because they push blood out of the heart.
The myocardium is thicker in the ventricles because of the force required to pump blood in a larger distance
*It is even thicker in the left ventricle then the right because it pushes farther.
What is the path of blood?
- from the body to the R. Atrium through both vena cava.
- the right atrium to the right ventricle
- the right ventricle through the pulmonary arteries to the lungs
- back from the lungs from the pulmonary veins to the left atrium.
- the left atrium to the left ventriclle
- the left ventricle through the aorta to the body
Describe Blood Vessels:
The three types of blood vessels are: arteries, veins, & capillaries
- Arteries- carry blood away from the heart (arteries have three layers)
- Veins carry blood towards the heart (veins also have the three layers but they have thinner smooth muscle & valves)
- Capillaries are the sites of all exchanges of material between blood & tissues (capillaries have a single layer of epithelium)
List the major structures of the conduction system of the heart:
The SA Node starts the conduction, sequence, contraction
- the SA node or pacemaker
- the AV node
- the AV bundle
- the purkinje system
Describe the heart:
The heart is called the cardiac cycle
- Systole- contraction; Diastole- relaxation
- Normal adult resting heart rate is 60-80 bpm
Name the five phases of the cardiac cycle:
- Artial systole (squeeze)- full of blood
- Isovolmetric Ventricular Contraction
- Ejection
- Isovolmetric Ventricular Relaxation
- Passive Ventricular Filling
What are the primary principles of circulation?
- Blood flows because a pressure gradiant exist between different parts of its volume.
- Peripheral Resistance to flow
What are the two factors affecting BP?
- Resistance to flow
* Total Volume
Describe the vasomotor mechanism:
Vasoconstriction makes BP increase.
Vasodilation makes BP decrease.
Friction between blood & the walls of vessels causes blood to slow down.
It is also influenced be viscosity
