Cardio Vascular System

Question 1

Where in the body is the heart located?

Answer 1

Mediastinum

Question 2

Name and describe the two coverings of the heart.

Answer 2

Fibrous Pericardium (wall of the cavity): its outermost layer is comprised of dense irregular connective tissue and it anchors the wall to the surrounding structures such as the diaphragm

Serous Pericardium: comprised of two groupings the first being parietal pericardium which is fused to the fibrous pericardium and composes the pericardial sac. secondly, the visceral pericardium is fused to the heart wall. between these layers is serous fluid.

Question 3

There are three parts to the heart wall… name them and their composition.

Answer 3

1 - Epicardium: which is essentially visceral pericardium and it is composed of stratified squamous epithelium and connective tissues
2 - Myocardium: cardiac muscle which is arranged in spiral or circular patterns reinforced with connective tissues
3 - Endocardium: simple squamous epithelium and connective tissues; endothelium lines the inside of all blood vessels and the inner surface of heart

Question 4

What are the four chambers of the heart and their associated blood vessels?

Answer 4

1: Right Atrium - inferior and superior vena cava and posteriorly coronary sinus
2: Left Atrium - 4 pulmonary veins
3: Right Ventricle - pulmonary trunk, divides in two to form the pulmonary arteries
4: Left ventricle - aorta

Question 5

What are the two different septa?

Answer 5

One septum, the interatrial, separates the atriums. The second septa, the interventricular septa, separates the ventricles and causes the interventricular sulcus.

Question 6

What is the most important aspect of the fibrous skeleton?

Answer 6

The fact that it allows for electrical insulation preventing simultaneous contraction of the atria and ventricle

Question 7

Name the two types of valves in the heart.

Answer 7

1: Atrioventricular Valves (AV) - we have the bicuspid which is on the left side and has two cusps; and the tricuspid which is on the right and has three cusps. Chordae tendineae attaches cusps to papillary muscles to prevent eversion
2: Semilunar valves - 3 cusps each including the aortic separating the aorta and left ventricle, and the pulmonary separating the right ventricle and the pulmonary trunk.

Question 8

Name the differences between skeletal muscle and cardiac muscle.

Answer 8

1 - branched
2 - uninucleated
3 - intercalated discs - regions, where two cells meet, are connected by gap and anchoring junctions

Question 9

Name the five parts of the cardiac conduction system.

Answer 9

1 - sinoatrial node: located at the right atrium at the bottom of the superior vena cava - sets the pace
2 - Atrioventricular node: base at the right atrium
3 - Atrioventricular bundle (bundle of His): superior part of the interventricular septum
4 - AV bundle branches: go to each ventricle
5 - Purkinje fibers - terminal fibers in ventricles

Question 10

List the pulmonary circulation.

Answer 10

Right ventricle - pulmonary arteries - capillaries in lungs - pulmonary veins - left atrium

Question 11

List the coronary circulation.

Answer 11

left ventricle - aorta

• right coronary artery - right marginal artery - or - posterior interventricular artery
• left coronary artery - anterior interventricular artery - or - circumflex artery
• arterioles - capillaries in myocardium - venules - cardiac veins - coronary sinus - right atrium

Question 12

Differences between adult blood circulation and fetal circulation?

Answer 12

1 - umbilical vein - carries oxygenated blood from the placenta to vena cava
2 - lungs and liver basically non-functional (three shunts to bypass = ductus venosus - permits blood to bypass liver blood mixes in vena cava of fetus, foramen ovale - hole in interatrial septum bypasses lungs, ductus arteriosus - connects pulmonary trunk and aorta)
3 - umbilical arteries return mixed-blood back to placenta

Question 13

Describe the general structure of blood vessels.

Answer 13

1 - tunica externa - CT
2 - tunica media - smooth muscle and elastic fibers
3 - tunica interna - endothelium - simple squamous
4 - lumen - contains blood

Question 14

Characteristics of blood, name three.

Answer 14

• higher viscosity than water
• 37 degrees celcius
• pH between 7.35-7.45
• 4-6 L in adult humans

Question 15

List the composition of blood plasma.

Answer 15

90% water
8% proteins
     - Albumins - control water balance 
     - Fibrinogens - clot formation
     - Globulins - antibodies 
2% solutes 
     - nutrients, hormones, wastes, electrolytes, gases

Question 16

Name the blood cell:

• makes up 45% of blood cells
• biconcave discs
• anucleated
• life-span of 120 days
• containing hemoglobin

Answer 16

Red blood cells - Erythrocytes

Question 17

Name the blood cell:

• nucleated
• life span varies
• defends against disease

Answer 17

White blood cells - Leukocytes

Question 18

Name and describe the three types of Granulocytes

Answer 18

1 - Neutrophils make up 60% of wbc and are phagocytic
2 - Eosinophils make up 3% of wbc and attack parasites
3 - Basophils make up 1% of wbc and release histamine which increases inflammation and decreases clotting

Question 19

Name and describe the two types of Agranulocytes

Answer 19

1 - Lymphocytes are 35% of wbc and help with human immunity. T lymphocytes kill diseased cells directly while B lymphocytes become antibodies
2 - Monocytes 5% of wbc which enlarge and become macrophages - phagocytic

Question 20

What is Hemopoeisis and where does it occur in the human body?

Answer 20

It is the formation of all blood cells which happens in the red bone marrow (hemocytoblasts) in the pelvic and pectoral girdles and proximal ends of the femur and humerus.