#01: Blood I

Question 1

What Kind of Tissue is Blood?

Answer 1

• Blood is considered a connective tissue cause it contains cells, a liquid ground substance (plasma), & dissolved proteins.

Question 2

Blood Temperature

Answer 2

• Temperature of blood is 1 degree Celsius higher than measured body temperature.

Question 3

Blood Centrifuge Process

Answer 3

• Whole blood can be separated into its liquid & cellular components by using a centrifuge.

1. Blood is withdrawn & collected in a glass tube (centrifuge tube).
2. The centrifuge tube is placed into the centrifuge, which then spins it in a circular motion for several minutes.
3. The movement separates blood into liquid & cellular components based on weight, thus allowing these elements to be examined apart.

Question 4

Blood Centrifuge Content

Answer 4

• Blood composition is made of erythrocytes, a buffy coat, & plasma when placed in centrifuge tube.
○ Erythrocytes form lower layer of centrifuged blood. 44%.
○ Buffy coat middle layer. This thin, slightly gray-white layer is composed of leukocytes & platelets. Less than 1%.
○ Plasma is straw-colored liquid on top. 55% of blood.

Question 5

Blood as a Transporter

Answer 5

• Blood is heavily involved in transportation. Example is erythrocytes & plasma carry oxygen from lungs to body cells & then transport carbon dioxide from cells to lungs. Plasma transports nutrients that were absorbed from GI tract. It also does hormones, & wastes.

Question 6

Blood as Temperature Regulator

Answer 6

• Blood regulates body temperature. Plasma particularly absorbs & distributes heat throughout the body. To cool, vessels in dermis dilate and dissipate the excess heat through the integument. When need to warm, the vessels constrict & warm blood is shunted 2 deeper vessels of body.

Question 7

Blood as pH Regulator

Answer 7

• Blood also regulates pH. Plasma has compounds/ions that may be distributed to the fluid to maintain it. The pH of the plasma itself is maintained at 7.4.

Question 8

Acidosis

Answer 8

• If blood plasma pH was 7.0, acidosis results. CNS is depressed, coma and death can occur.

Question 9

Alkalosis

Answer 9

• If blood plasma pH was 7.8, alkalosis results. Hyperexcited nervous system and convulsions.

Question 10

Blood as Fluid Level Regulator

Answer 10

• Blood regulates normal fluid levels in the cardiovascular system & prevents blood loss. A constant exchange of fluid takes place between the blood plasma & the interstitial fluid.
○ If blood gets too much fluid, high blood pressure. If too much fluid escapes the bloodstream, blood pressure drops to unhealthily low levels & tissues swell with excess fluid.

Question 11

How Leukocytes Fight Infection

Answer 11

• Leukocytes fight infection by mounting an immune response if a pathogen or antigen is found. Antibodies (molecules that bind to antigens until a leukocyte can kill or remove it) are transported in plasma.

Question 12

Blood Plasma Contents & Serum

Answer 12

• Blood plasma is a complex mix of H2O, proteins, & other solutes. When blood cells, platelets, & clotting proteins are removed from plasma, remaining fluid is serum.
• H2O most abundant in plasma, 92% of total blood plasma volume. Plasma proteins 7% of plasma.

Question 13

Alumins

Answer 13

○ Albumins are smallest/most abundant protein. Regulate H2O movement between blood & interstitial fluid by providing some of the plasma solutes to drive osmosis. They also act as transport proteins that carry ions, hormones, & some lipids in blood.

Question 14

Globunins & Gamma-globunins

Answer 14

○ Globunins 2nd largest group of proteins. The smaller alpha-globunins & larger beta-globulins bind, support, & protect certain H2O-insoluble or hydrophobic molecules, hormones, & ions.

§ Gamma-globunins (also immunoglobunins or antibodies) are soluble proteins made by defense cells to protect body against pathogens.

• Some globunins are transport proteins (steroid binding proteins).

Question 15

Fibrinogen

Answer 15

A plasma protein. Fibrinogen responsible for blood clot formation. It’s converted into long, insoluble strands of fibrin, which helps form a blood clot.

Question 16

Plasma vs. Interstitial Fluid: Gas Transport

Answer 16

• Plasma & interstitial fluid have similar concentrations of most dissolved products, nutrients, & electrolytes, except plasma proteins. Concentration of oxygen is higher in plasma since cells take up and use oxygen from interstitial fluid during energy production. This difference ensures that oxygen will diffuse from blood into interstitial fluid. Similarly, concentration of carbon dioxide is lower in blood cause cells produce carbon dioxide during energy production that gets into interstitial fluid. Cause of difference, carbon dioxide will diffuse into blood so it can leave the body.

Question 17

Hematocrit

Answer 17

• Hematocrit is the % of volume of all formed elements in the blood. Can also mean % of erythrocytes, though difference between both #s is negligible.

Question 18

Mature Erythrocytes Cells?

Answer 18

• Mature erythrocytes lack nuclei & organelles, so it’s more appropriate to call it a formed element.

Question 19

Erythrocyte Biconcave Disc Structure

Answer 19

• Erythrocyte’s biconccave disc structure allows respiratory gases to be loaded & unloaded rapidly & efficiently.

Question 20

Hemoglobin Function

Answer 20

• Hemoglobin transports oxygen and carbon dioxide, and is responsible for the bright red color of arterial blood.
• Hemoglobin gives erythrocytes a red color due to the iron in it.

Question 21

Hemoglobin Structure

Answer 21

• Each hemoglobin molecule has 4 polypeptide chains called globins. Two of these are called alpha chains, the other two slightly different ones are called beta chains. Each chain contains a nonprotein (or heme) group that’s in the shape of a ring, with an iron ion in its center. Oxygen binds to these iron ions for transport in the blood. With 4 chains, each hemoglobin molecule can bind 4 molecules of oxygen.

Question 22

How Strong is Hemoglobin’s Bond to Oxygen?

Answer 22

• The oxygen binding of hemoglobin is weak for rapid attachment/detachment of oxygen.

Question 23

What Controls Cardiovascular System?

Answer 23

• The cardiovascular system is controlled primarily through homeostatic reflexes, but is also controlled by local factors, CNS input, & hormones.

Question 24

Total Blood Volume

Answer 24

• The total blood volume is proportional to body & is, on average, 4-5 L in females & 5-6 L in males.

Question 25

Plasma Buffers

Answer 25

• Plasma Buffers: Many plasma solutes act as buffers, which can absorb acids & bases without changing the body’s pH. Without them, carbon dioxide would affect blood pH.

Question 26

Colloid

Answer 26

• Plasma is a colloid, a mixture where a solute-like substance is dispersed throughout a solvent-like substance.

Question 27

Formed Elements

Answer 27

• Formed elements are blood components with a cell membrane that may or may not have a nucleus. If a volume of whole blood is centrifuged, the formed elements are separated from the plasma.

Question 28

Leukocyte Component

Answer 28

• Leukocytes have a nucleus & some have granules that can be differentially stained.

Question 29

Advantage of Erythrocyte Biconcave Disc

Answer 29

• Biconcave shape of erythrocytes increases surface-volume ratio of the cell & facilitates erythrocyte movement through blood vessels. The greater surface area increases efficiency of gas diffusion in & out of cell. The thin center allows erythrocytes to bend or fold, letting the move through small vessels.

Question 30

How Erythrocyte Structure is Maintained

Answer 30

• The erythrocyte concave shape is maintained by interaction of spectrin with the cell cytoplasm, & spectrin gives the erythrocyte elastic abilities so it’s not damaged when it collides with walls or bent & squeezed through small openings.

Question 31

How Are Erythrocytes Stopped From Clumping?

Answer 31

• Negative charges on surface of glycoporin prevent erythrocytes from clumping.

Question 32

Heme Group

Answer 32

• Each subunit in hemoglobin contains a heme group, which is a large organic molecule that contains one iron atom in middle of a planar ring.