Blood Tissue Concepts

Question 1

Be able to fit blood into our Connective Tissue outline.

Answer 1

Liquid connective tissue
- Blood
- Lymph

Question 2

Describe the 3 functions of blood and how each relates to homeostasis. (Consider the statement that blood is the tissue most responsible for maintaining homeostasis. Do you agree or disagree?)

Answer 2

1) Transport
- Out to in. oxygen and nutrients
- In to out. CO2, H2O, nitrogen waste
- Internally: hormones from the anterior pituitary to target organs
2) Regulate
- pH (buffers)
- Body temperature
- Osmolarity of cells
3) Protect
- Platelets clot against blood loss
- Leukocytes keep you alive
- Blood proteins protect against disease

Question 3

Relate intracellular, interstitial, extracellular, and intravascular fluid to one another.

Answer 3

intracellular= fluid within cells
interstitial= fluid between the cells/ surrounding cells
intravascular= fluid within the blood vessels
extracellular= combination of interstitial and intravascular fluid

Question 4

Describe the physical characteristics and principal components of blood.

Answer 4

Blood plasma 55%,
- “Plasma proteins” are albumin, globulin, fibrinogen
- Water
- Other solutes
Formed elements 45%
- Red blood cells 99%
- White blood cells
- platelets

Question 5

Contrast the variability (and reasons for or against) of RBCs, WBCs, and platelets.

Answer 5

Red blood cells= controlled by negative feedback loops
White blood cells= fluctuate depending on immune status
platelets= controlled by negative feedback loops

Question 6

Describe the location and key structures involved in hematopoiesis.

Answer 6

Occurs in red marrow
- Spaces between trabeculae of spongy bone
- The axial skeleton, pectoral and pelvic girdle, and proximal epiphyses of the humerus and femur

Question 7

Describe the two cell lines formed from a pluriopotent stem cell and the offspring of both lines

Answer 7

Myeloid stem cell= formed fully in the red marrow
- Offsprings are red blood cells, platelets, eosinophils, basophils, neutrophils, monocyte

Lymphoid stem cell= are partially formed in red marrow and then released in the lymphatic system via the circulatory system where they are fully formed
- Offspinrgs are T lymphocyte, B lymphocyte, Natural killer cell

Question 8

Discuss the conservation of the sequence: “progenitor, -blast, -cyte” as it pertains to hematopoiesis

Answer 8

Go to a progenitor cell (colony forming unit), then go to a -blast, then go to a -cyte (or -phil)

Question 9

Name and describe the role of a few key hematopoietic growth factors.

Answer 9

Erythropoietin= produced in the kidney, it increases the number of red blood cell precursors (progenitor)

Thrombopoietin= produced in the liver, stimulates the formation of Megakaryocytes, which then crumbles into thousands of platelets (little cell “bits” for blood clotting)

Cytokines= glycoproteins that generally stimulate the production of many hematopoietic precursors

Question 10

Describe the structure, functions, life cycle, and production of red blood cells in detail.

Answer 10

Structure: biconcave shape, a bag of hemoglobin, tough and durable cell membrane

Function: carry oxygen from the lungs to cells, CO2 to the lungs to excretion
Life cycle:3-4 months

Production:
Pluripotent stem cell
Myeloid stem cells
CFU - E progenitor cells
Proerythroblast
Reticulocytes
Mature erythrocytes

Question 11

Describe the structure, functions, and production of white blood cells (WBCs).

Answer 11

Structure: huge nuclei and organelles for aerobic metabolism, granules, and MHC antigens protruding from cell membranes
Functions: massive component of immune response
Production:
Pluripotent stem cell
Myeloid stem cell
CFU-GM
-blast
-phil

Question 12

Discuss the mechanisms of diapedesis, or “emigration” of WBCs from blood vessels to tissues, also describing phagocytosis in general terms.

Answer 12

Blood vessels are deep in the epidermis, and foreign invasion is usually superficially found. So, the WBC “emigrates” via diapedesis, from vessels into surrounding tissues to deal with inflammation and invasion. Granular leukocytes and monocytes migrate permanently, while lymphocytes can return to vessels.

Phagocytosis is “eating cells” that ingest bacteria.

Question 13

Contrast the final location of plasma cells, mast cells, and macrophages, as compared to the majority of other blood cells.

Answer 13

Plasma cells, mast cells, and macrophages permanently live in loose areolar connective tissue.
The majority of other blood cells are found in the red bone marrow.

Question 14

Describe the structure, function, and origin of platelets.

Answer 14

Structure: Small

Function: critical to blood clotting

Origin:
Pluripotent stem cell
Myeloid stem cell
CFU - Meg progenitor cell
Megakaryoblast
Megakaryocyte (huge precursor cell that splinters into a couple of thousand small fragments each completely wrapped in cell membranes)
Platelets

Question 15

Describe vascular spasming, functionally, and how it is initiated.

Answer 15

Vascular spasming= the quickest, most effective solution is to constrict the injured blood vessel to narrow the diameter, decreasing blood flow through the vessel, and minimizing blood loss.
Direct damage to the tissue surrounding the damaged vessel can trigger the release of local chemicals that stimulate smooth muscle contraction to constrict the blood vessel to try to limit blood loss.

Question 16

Describe platelet plug formation, how platelets are activated, and what sort of small positive feedback loop is involved in this activation.

Answer 16

Platelet plug formation= if platelets are “activated,” they’ll stick to collagen fibers in the C.T. superficial to the endothelial cells and they’ll stick to each other.
- When platelets become active, they release ADP into the blood to stimulate an inactive platelet to become activated. The newly activated platelet will join and fill the platelet aggregation. The newly activated platelet will release ADP and continue the cycle of recruiting newly activated platelets, which will also release ADP. This positive feedback loop of releasing ADP from activated platelets to recruit more activated platelet occurs to keep you alive.

Question 17

Describe the coagulation cascade very briefly, contrasting the intrinsic and extrinsic pathways, and concentration on the formation of insoluble fibrin fibers.

Answer 17

Coagulation cascade= We need a clot so we incorporate platelets and RBC and insoluble fibrin fibers all locked together in a solid, immobile clot, while vessels are being repaired
Intrinsic pathway:
Factors that are found in the lumen of the blood, pathway will always be active (drop of blood hitting kitchen counter)
Extrinsic pathway:
Quicker, short within seconds, relies on factors extrinsic to the blood (tissue factor, smooth muscle), uses material outside of the blood to get the pathway going
These two pathways come together to meet at a common pathway (production of thrombin)

Question 18

Describe clot retraction and mitotic cell repair.

Answer 18

Clot retraction= leaving the clot in place and tending to the vessel and surrounding C.T. (deep wound healing)
Mitotic cell repair= platelets now release platelet-derived growth factor, a hormone that stimulates mitosis of the endothelial cells

Question 19

Describe fibrinolysis

Answer 19

fibrinolysis= the breakdown of blood clots so it doesn’t flow downstream and obstruct smaller diameter blood vessels
Endothelial cells host a protein in their membrane that helps form Plasmin, a key proteolytic enzyme that feeds on insoluble fibrin. As it disassembles the fibrin mesh, the blood clot is slowly broken down into its component pieces

Question 20

Discuss the role of Vitamin K in clotting factors and the role of antagonists in blood thinning.

Answer 20

Several precursors earlier in the series depend on Vitamin K for clotting. Having an antagonist of vitamin K in your body will block vitamin K incorporation and shut down blood clotting, thinning blood.

Question 21

Distinguish between the ABO and Rh blood groups.

Answer 21

ABO refers to blood types A, B, both, or neither.
Rh, refer to if your blood type is positive or negative.

Question 22

Understand how to type a person’s blood.

Answer 22

To figure out blood type: put one drop of blood in 3 heparin-coated tubes:
One drop of serum full of anti-a antibodies in one tube
One drop of serum full of anti-b antibodies to another
Leave 3rd tube untreated as a control group

Do the same with a serum fill of anti-Rh antibodies and you’ll know if you’re a + or - blood type
If the blood appears separated from the serum, you’re a + and if it doesn’t clump then you’re a -

Question 23

Explain why it is so important to match donor and recipient blood types before administering a transfusion, and how antigens and antibodies work and interact with one another when considering possible blood transfusions.

Answer 23

Antigens= sugars that you have in your RBCs
antibodies= immunoproteins that you make to fight against any molecule in your body that seems “foreign”
If you receive a blood transfusion from a person whose type has foreign antigens to your blood, the foreign antigen will be a threat to you and your antibodies will attack the antigen in the transfused blood. This antigen-antibody binding will result in your RBC clumping inappropriately, causing problems (stroke)

Question 24

Understand the development of hemolytic disease in the newborn.

Answer 24

A pregnant mother will have no anti-Rh antibodies the first time she’s pregnant so when a little blood from the first Rh+ baby crosses the placenta into the mother’s blood, her blood will be presented with “foreign” Rh antigens. So, she’ll make anti-Rh antibodies. Meaning, if the 2nd or 3rd child is a Rh+ fetus, her anti-Rh antibodies can cross the placenta and attack the Rh antigens in the fetus’s RBC, which can cause problems.

Question 25

How many globins make hemoglobin?

Answer 25

4 globins