Unit 12: Cardiovascular System

Question 1

What cavity is the heart located in?

Answer 1

The mediastinum (space between lungs)

Question 2

What is the endocardium and what is it composed of?

Answer 2

The endocardium lines the inner surface of the heart and is composed of simple squamous epithelium (endothelium) and connective tissue

Question 3

What are the 3 major veins that connect to the right atrium and carry deoxygenated blood into the chamber?

Answer 3

Inferior vena cava (below heart)
Superior vena cava (above heart)
Coronary sinus (from the myocardium)

Question 4

What veins carry oxygenated blood into the left atrium?

Answer 4

There are 4:
Left pulmonary veins
Right pulmonary veins

Question 5

How many blood vessels leave the left ventricle?

Answer 5

Just 1 artery, the aorta

Question 6

What blood vessels connect to the right ventricle?

Answer 6

The pulmonary trunk exits the right ventricle and then divides to form the left and right pulmonary arteries

Question 7

What separates the chambers within the heart?

Answer 7

The septa: the interatrial septum and the interventricar septum

Question 8

What is the cardiac (fibrous) skeleton?

Answer 8

It separates the atria and ventricles and provides solid attachment points, forms rings around valves, and electrical insulation for SA node. It is composed of fibrous connective tissue.

Question 9

What are chordae tendineae?

Answer 9

Strings of CT that attach AV valve cusps to papillary muscles that project from the ventricular myocardium. They prevent leakage or backflow through cusps by sealing them shut

Question 10

What are the 2 types of cardiac muscle cells?

Answer 10

Contractile cells and conduction system cells

Question 11

Describe contractile cells. How do they differ from skeletal muscle?

Answer 11

Contractile cells form the majority of the myocardium and are striated with sarcoplasmic reticulum and T-tubules. Unlike skeletal muscles, they are branched, uninucleated (1 nucleus), connected by intercalated discs, and contain anchoring and gap junctions

Question 12

Describe conduction system cells

Answer 12

Forms the remainder of the myocardium. The cells are modified to produce and conduct electrical impulses (they don’t contract). They have many gap junctions to help electrical impulses spread quickly

Question 13

What are the parts of the conduction system of the heart?

Answer 13

Sinoatrial (SA) node
Atrioventricular (AV) node
AV bundle (bundle of his)
AV bundle branches
Purkinje fibres

Question 14

What makes up the general structure of blood vessels?

Answer 14

Tunica extrna (CT)
Tunica media (smooth muscle and elastic fibres (CT))
Tunica intima/interna (endothelium)
Lumen (contains blood)

Question 15

Describe the 2 types of artery

Answer 15

Elastic arteries: largest arteries close to the heart, elastic CT in all 3 layers
Muscular arteries: makes up most arteries, smooth muscle, smaller

E.g. aorta (EA) vs coronary (MA)

Question 16

Which type of blood vessel is only composed of tunica intima (endothelium + basement membrane)?

Answer 16

Capillaries

Question 17

Give some examples of subdivisions of systemic circulation (the names or routes to individual organs)

Answer 17

Routes to individual organs:
Cerebral = brain
Hepatic = liver
Coronary = heart
Bronchial = respiratory system

Question 18

What are some characteristics of blood?

Answer 18

CT
Higher viscosity that H2O
pH = 7.35 - 7.45
4-6 L in an adult

Question 19

90% of plasma is made up of water. 8% is proteins. What are the major proteins?

Answer 19

Albumins: most plentiful, carries hormones, enzymes, and meds through the body, helps tissue water balance
Fibrinogen: clot formation
Globulin: antibodies
Protein-based hormones and enzymes

Question 20

What are the types of leukocytes (WBC)?

Answer 20

Granulocytes, contain visible protein
Agranulocytes, do not contain visible protein granules

Question 21

What are the types of lymphocytes?

Answer 21

T Lymphocytes: activate immune system, can kill virus or tumour cells directly
B Lymphocytes: become plasma cells that release antibodies that circulate in the plasma

Question 22

What are monocytes?

Answer 22

A type of agranulocyte that enters a tissue and enlarge to become macrophages (“big eaters”) phagocytic

Question 23

The pericardium is the protective sac surrounding the heart. What layers does it have?

Answer 23

Fibrous pericardium: DI-CT, anchors to surrounding structures
Parietal pericardium: epithelial and connective tissue, pericardial sac
Visceral pericardium (epicardium): epithelial and connective, fused to heart surface—part of heart wall

Question 24

What is the name for the formation of blood cells?

Answer 24

Hemopoiesis/hematopoiesis. All blood cells arise indirectly from hemocytoblast cells (type of stem cell)

Question 25

What is atrial septal defect?

Answer 25

A hole in the interatrial septum, which commonly occurs due to incomplete formation of the foramen ovale

Question 26

Granulocytes are a type of WBC. What makes up the visible granules within?

Answer 26

Neutrophils (majority)
Eosinophils
Basophils

Question 27

Platelets are fragments of cells called _______.

Answer 27

megakaryocytes

Question 28

What are the 3 fetal shunts that allow most blood to bypass the lungs and liver?

Answer 28

Ductus venosus
Foramen ovale
Ductus arteriosus

Question 29

In fetal circulation, which shunt permits the oxygenated blood coming from the placenta via the umbilical vein to bypass the liver capillaries to go straight to the inferior vena cava?

Answer 29

Ductus venosus

Question 30

In fetal circulation, which shunt connects the pulmonary trunk and aorta to allow blood to bypass the lungs?

Answer 30

Ductus arteriosus