BIOL Lab 9: Cardiovascular System

Question 1

FETAL vs ADULT CIRCULATION: Umbilical cord circulation

Answer 1

The first major difference between fetal and adult circulation:

Umbilical cord circulation: this collection of vessels allows oxygen and nutrients to pass from the mother to the fetus and carbon dioxide and metabolic waste to pass from the fetus to the mother.

Umbilical arteries carry deoxygenated blood and wastes from the fetus to the mother

Umbilical vein carries oxygenated blood and nutrients from the mother to the fetus.

Question 2

FETAL vs ADULT CIRCULATION: Ductus arteriosus

Answer 2

The second major difference between fetal and adult circulation:

Ductus arteriosus: a connection between the pulmonary artery and aorta that shunts blood from the pulmonary artery to the aorta, allowing a large quantity of blood to bypass the lungs.
- Since the fetus is not breathing with its lungs (oxygenated blood comes from the mother via the umbilical vein), only a small fraction of blood leaving the right ventricle needs to go to the lungs to deliver oxygenated blood to the lung tissue to help it develop.

Question 3

FETAL vs ADULT CIRCULATION: Foramen ovale

Answer 3

The third major difference between fetal and adult circulation:

Foramen ovale: an opening in the septum between the right and left atria to allow blood passing into the right atrium to be channeled into the left atrium, mostly bypassing the lungs (see *)
- Since the fetus is not breathing with its lungs (oxygenated blood comes from the mother via the umbilical vein), only a small fraction of blood leaving the right ventricle needs to go to the lungs to deliver oxygenated blood to the lung tissue to help it develop.

Question 4

Heart Murmur

Answer 4

Hissing sound that occurs when blood squirts backward through a leaky valve in the heart.

Question 5

Do All Veins Carry Deoxygenated Blood?

Answer 5

No, because pulmonary veins carry oxygenated blood.

Question 6

Do All Arteries Carry Oxygenated Blood?

Answer 6

No, because pulmonary arteries carry deoxyginated blood.

Question 7

Artery and Vein Tissue Layers

Answer 7

Tunica Adventitia: Outer layer, composed of connective tissue and elastic vibers.

Tunica Media: middle layer, composed of smooth muscle and some elastic fibers.

Tunica Intima: Inner layer, composed of endothelium – simple squamous epithelium.

Question 8

Atherosclerosis

Answer 8

Build up of plaque within the walls of the heart’s arteries can impede blood flow – leading to total obstruction, arrhythmia, or increased probability of a blood clot.

Question 9

Blood

Answer 9

55% is plasma. Other 45% is blood cells.

Plasma is 90% water and 10% inorganic salts, ions, proteins, hormones, and metabolic wastes.

Blood is a special type of connective tissue; it is comprised of three main classes of formed elements; erythrocytes, platelets, and leukocytes.

Question 10

Erythrocytes

Answer 10

Red blood cells. Most abundant. Comprise approximately 45% of total blood volume. Small, flattened biconcave discs. Mature RBCs lack a nucleus and are the primary vehicles of gas exchange via hemoglobin. A hemoglobin molecule is comprised of four polypeptide chains (two alpha chains and two beta chains).

Transports oxygen.

Question 11

Platelets

Answer 11

Also thrombocytes. Smallest of formed elements. Actually cell fragments derived from committed stem cells in the bone marrow. Main function is to initiate the process of blood clotting. Like erythrocytes, platelets also lack a nucleus.

Circulates blood.

Question 12

Leukocytes

Answer 12

White blood cells. They fight infections and produce antibodies. Unlike erythrocytes, which are confined to the vascular system, leukocytes can move out of blood vessels to seek out and destroy invaders such as bacteria, viruses, parasites, toxins, and tumor cells. Can also digest debris from dead/injured tissue. Normally in small numbers, unless in times of infection.

Grouped in two main categories, granulocytes and agranulocytes.

Question 13

Granulocytes

Answer 13

Type of leukocytes. Have deeply stained particles in cytoplasm.

Neutrophils (55-70%) - Nucleus has 1 to 5 lobes; the cytoplasm contains fine, red stained granules.

Eosinophils (1-4%) - The nucleus is bilobed; the cytoplasm contains large, orange-red stained granules.

Basophils (0.5-1%) - Nucleus typically bilobed; the cytoplasm contains purple-blue stained granules.

Question 14

Agranulocytes

Answer 14

Type of leukocytes. Show no apparent particles in the stained cytoplasm.

Lymphocytes (20-30%) - Usually smallest. Nucleus is large, round, darkly stained, and occupies most of cell.

Monocytes (2-8%) - Typically largest. The nucleus is either round or kidney-shaped and the cell contains a large cytoplasm.

Question 15

Sickle Cell Anemia

Answer 15

A hereditary condition that results in abnormal
hemoglobin production and misshapen red blood cells.
These sickle-shaped cells are inefficient at carrying oxygen
and can easily clog capillaries and can have fatal effects.

Question 16

Leukemia

Answer 16

Type of cancer that involves overproduction of leukocytes. These cells are often immature or abnormal in appearance and lack normal function. There are several different forms of leukemia and these are distinguished and named by the primary cell type(s) involved.

Question 17

High Diastolic Blood Pressure

Answer 17

If too high, it means the blood vessels have lost their elasticity relative to the amount of blood they are carrying. This can lead to stroke, kidney problems, etc.

Question 18

Sphygmomanometer

Answer 18

Apparatus used to measure blood pressure. Also blood pressure cuff. Measures blood pressure in the brachial artery, main artery of arm.

Question 19

Antigen

Answer 19

Substance that elicits an immune response by binding receptors of B cells, antibodies, or of T cells.

Question 20

Antibody

Answer 20

Protein secreted by plasma cells that binds to a particular antigen.

Question 21

Agglutination

Answer 21

A clumping of RBCs when held together by antibodies.