Circulatory system

Question 1

whole blood consists of:

Answer 1

55% plasma and 45% formed elements: erythrocytes (red blood cells), leukocytes (white blood cells), and platelets.

Question 2

all of the formed elements are produced from:

Answer 2

stem cells in red bone marrow

Question 3

Erythrocytes are modified for transport of

Answer 3

oxygen where most of it is bound to the pigmented protein hemoglobin

Question 4

the 5 types of leukocytes can be distinguished on the basis of:

Answer 4

size, appearance of the nucleus, staining properties, and the presence or absence of visible cytoplasmic granules

Question 5

white blood cells are active in:

Answer 5

phagocytosis (neutrophils and monocytes) and antibody formation (lymphocytes)

Question 6

platelets are active in the process of

Answer 6

blood clotting

Question 7

blood serves to transport __________ and to carry away _________.

Answer 7

oxygen and nutrients; carbon dioxide and metabolic wastes

Question 8

plasma contains approx. ___________ which are dissolved or suspended in water

Answer 8

10% proteins, ions, nutrients, waste products and hormones

Question 9

the heart is a double pump that sends blood to the lungs for oxygenation through

Answer 9

the pulmonary circuit and to the remainder of the body through systemic circuit

Question 10

blood is received by the _______ and is pumped into circulation by the ________

Answer 10

atria; ventricles

Question 11

valves between the atria and ventricles include

Answer 11

the tricuspid on the right side of the heart and bicuspid on the left

Question 12

semilunar valves are found at the

Answer 12

entrance of the pulmonary trunk and the aorta

Question 13

blood supplies to the heart muscle (the myocardium) by

Answer 13

the coronary arteries

Question 14

blood drains from the myocardium directly into the

Answer 14

right atrium through the coronary sinus

Question 15

the heart has an intrinsic beat initiated by the

Answer 15

sinoatrial node and transmitted along a conduction system through the myocardium

Question 16

the cardiac cycle is the period from the end of

Answer 16

one ventricular contraction to the end of the next ventricular contraction

Question 17

the contraction phase of the cycles is

Answer 17

systole

Question 18

the relaxation phase is

Answer 18

diastole

Question 19

the vascular system includes

Answer 19

arteries that carry blood away from the heart, veins that carry blood toward the heart, and the capillaries

Question 20

the capillaries, the smallest of vessels, are where the exchange of ___________ take place between the blood and surrounding tissues.

Answer 20

water, nutrients, and waste products

Question 21

the systemic arteries begin with the

Answer 21

aorta which sends branches to all parts of the body

Question 22

as arteries get farther away from the heart they become

Answer 22

thinner and thinner

Question 23

what are the smallest arteries called?

Answer 23

arterioles

Question 24

what are the large veins that empty into the right atrium of the heart?

Answer 24

superior and inferior vena cava

Question 25

the walls of the arteries are ____ and _____ and they carry blood under ______

Answer 25

thick; elastic; high pressure

Question 26

vasoconstriction and vasodilation result from

Answer 26

contraction and relaxation fo smooth muscle in the arterial walls; these changes influence blood pressure and blood distribution to the tissues

Question 27

the walls of the veins are _____ and ____ than those of the arteries and they carry blood under ______.

Answer 27

thinner; less elastic; lower pressure