Exam 3: Circulatory System 1: Blood and Vessels

Question 1

Blood (Intro Info)

Answer 1

• connective tissue

- ground substances is plasma

Question 2

Plasma

Answer 2

• Contains water, antibodies, proteins, respiratory gases

- 99% of blood

Question 3

Formed Elements

Answer 3

• blood cells
• erythrocytes (red blood cells) 44%
• leukocytes (white blood cells) both
• platelets (thrombocytes)
• WBC’s and platelets make up last 1% of total 45% of formed elements

Question 4

Erythrocytes

Answer 4

• shaped like biconcave discs
• anuculate
• life span of about 120 days
• filled with hemoglobin
• function: transports oxygen and carbon dioxide

Question 5

Breakdown of old Erythrocytes

Answer 5

• broken down by spleen and liver and parts are recycled
• old broken down
• components like heme and iron sent back to red bone marrow to make new erythrocytes

Question 6

Leukocytes (WBC’S)

Answer 6

• typically larger than erythrocytes
• function: generate an immune response, fight infection, etc
• able to slip out of capillary blood vessels (diapedesis)

Question 7

Neutrophils

Answer 7

• most numerous type of leukocyte
• cytoplasm has fine pale granules
• nucleus is multilobed (3-5)

Question 8

Eosinophils

Answer 8

• type of leukocyte
• cytoplasm contains prominent granules that stain reddish
• nucleus is bilobed

Question 9

Basophils

Answer 9

• make up less than 1% of all leukocytes
• cytoplasm contains big granules that stain blue/purplish
• bilobed nucleus

Question 10

Lymphocytes

Answer 10

• type of leukocyte
• cytoplasm lacks visible granules
• contains large, round dark purple nucleus, surrounded by a thin ring of pale blue cytoplasm
• most located in lymphatic tissues
• different kinds: T-lymphocytes, B-lymphocytes and natural kill cells

Question 11

Monocytes

Answer 11

• largest leukocyte
• cytoplasm lacks visible granules
• pale blue cytoplasm
• c-shaped or kidney-bean shaped nucleus

Question 12

Mnemonic for Leukocytes

Answer 12

Never (neutrophil)
Let (lymphocyte)
Monkeys (monocyte)
Eat (eosinyphil)
Bananas (basophil)
-from most to least common

Question 13

Platelets

Answer 13

• cytoplasmic fragments from larger cell
• anucleate
• limited life span ~5 days
• very small
• function: blood clotting

Question 14

Arteries

Answer 14

• take blood away from heart and to other tissues
• transport blood high in oxygen (exception; pulmonary arteries)
• wall structure: thicker than veins, lumen smaller than that of corresponding vein, retain circular shape
• blood pressure is higher in arteries than in veins

Question 15

Veins

Answer 15

• take blood to heart
• transport blood low in oxygen and high in carbon dioxide (exception: pulmonary veins)
• wall structure: thinner than artery, larger lumen than artery, walls tend to be collapsed when not filled with blood
• blood pressure is lower in veins

Question 16

Capillaries

Answer 16

• tiny vessels that connect arteries and veins

- responsible for gas and nutrient exchange between blood and tissues

Question 17

Pathway of Blood

Answer 17

-heart–>elastic arteries–>muscular arteries–>arterioles–>capillaries–>venules–>veins–>heart

Question 18

Tunica Externa

Answer 18

• outermost layer of blood vessels
• areolar connective tissue
• largest layer in veins
• Ex: aorta, and major branches of it
• send blood to smaller muscular arteries

Question 19

Tunica Media

Answer 19

• middle layer of blood vessels
• circularly arranged smooth muscle fibers
• largest layer in arteries
• sympathetic innervation typically causes vasoconstriction (narrows blood vessel walls, increases blood pressure)

Question 20

Elastic Arteries

Answer 20

• largest diameter
• vessel wall contains large amounts of elastic protein fibers
• aorta

Question 21

Muscular Arteries

Answer 21

• less elastic fibers than elastic arteries and more smooth muscle in tunica media
• most named arteries (radial, ulnar)
• send blood to arterioles
• medium sized diameter

Question 22

Arterioles

Answer 22

• smallest diameter

- tunica media consists of 6 or fewer layers of smooth muscle

Question 23

Capillaries

Answer 23

• vessel diameter is only slightly larger than the diameter of an erythrocyte
• have just tunica intima
• form capillary beds
• gas/nutirent exchange happens here

Question 24

Venules and Vens

Answer 24

• low pressure
• take blood back to heart
• tunica externa is thickest layer

Question 25

Venules

Answer 25

• collect blood from capillaries
• travel next to arterioles
• merge to form veins

Question 26

Veins

Answer 26

• formed when venules unite
• take blood back to heart
• most but not all veins have valves (prevent backflow of blood)

Question 27

Muscular Pumps

Answer 27

• also help blood be pushed in veins toward heart
• contraction of skeletal muscles
• ex: gastrocnemius and soleus pump blood from legs to heart
• if inactive, bedridden, long plane ride, blood could pool and clot in veins–>deep vein thrombosis (DVT)

Question 28

Vericose Veins

Answer 28

• may occur when valves become incompetent/stop working

- blood pools in veins and makes them bulge