Chapter 17 (Lecture) [Blood] Flashcards Preview

A&P 2 Lecture > Chapter 17 (Lecture) [Blood] > Flashcards

Flashcards in Chapter 17 (Lecture) [Blood] Deck (40)
Loading flashcards...
1
Q

Functions of Blood

A
  • Transportation of dissolved gases, nutrients, hormones and metabolic wastes
  • Regulation of pH and ion composition of interstitial fluids.
  • Restriction of fluid losses at injury sites
  • Defenses against toxins and pathogens
  • Stabilization of body temperature
2
Q

Proteins in Blood Plasma

A
  • Albumins
  • Globulins
  • Fibrinogens
  • Other stuff
    • Electrolytes & ions
    • Organic nutrients (Lipids, Amino acids, etc.)
    • Organic Wastes (Urea, uric acid, creatine, etc.)
3
Q

Why do Erythrocytes have a short life span?

A

Erythrocytes do not have a nucleus, meaning they can’t maintain the cell.

4
Q

What eats worn out blood cells?

A
  • Macrophages monitor conditions of RBCs in bloodstream, and engulf any before they hemolyze (burst).
  • Iron is extracted from heme, either stored in phagocyte or released to transferrin proteins.
  • Heme unit is converted into Biliverdin (green) then into Bilirubin and released into the bloodstream.
  • Bilirubin that was released by the macrophages binds to albumin & transported to the liver
  • Bilirybin is then excreted by bile, & then ultimately out of the body through defecation.
  • If bilirubin is NOT processed, it will diffuse into peripheral tissues & lead to jaundice.
5
Q

Hemoglobin

A
  • Quaternary structure
  • 2 alpha helices & 2 beta sheets per subunit (4 subunits)
  • Each helix and sheet contains a molecule of heme.
  • 95% of a RBC’s proteins
  • Abbrievated Hb
6
Q

Heme

A
  • Iron ion is held in such a way that it can interact with an oxygen molecule.
  • The bond between O2 and Fe is weak and is easily reversible.
  • When bound: oxyhemoglobin → bright red
  • When released: deoxyhemoglobin → dark red
7
Q

Where is blood made?

A

Hematopoeiesis

Produced in the Red Bone Marrow

  • Found in:
    • Sternum
    • Vertebrae
    • Ribs
    • Skull
    • Scapulae
    • Pelvis
    • Proximal limb bones
8
Q

Oxygenated Blood

A
  • Found in:
    • Pulmonary Vein
    • Systemic Artery
  • Color
    • Bright Red
9
Q

Deoxygenated Blood

A
  • Found in:
    • Pulmonary Artery
    • Systemic Vein
  • Color
    • Dark Red
10
Q

Plasma

A
  • Makes up between 46%-63% blood
  • Similar to interstitial fluid, same for O2 & CO2 content & types of proteins within.
  • Proteins of plasma are too large to leave bloodstream.
11
Q

Properties of Blood

A
  • Temperature is slightly above normal body temperature. (~100)
  • Thicker than water by about 500% (Due to proteins, formed elements, & water molecules in plasma)
  • Slightly basic. Normal pH range is 7.35-7.45
  • Average adult has 5 liters of blood (Can sustain loss of up to 40%)
12
Q

Albumins (In Plasma)

A

Majority of proteins, contribute to osmotic pressure of blood.

13
Q

Globulins (In Plasma)

A
  • About 35% of plasma proteins, include antibodies & transport globulins (mostly ions, hormones, lipids, etc.)
  • Play a role in immune system
14
Q

Fibrinogen (In Plasma)

A

About 4% can interact to form large strands of fibrin, the basic network for blood clots.

15
Q

Formed Elements of Blood

A
  • Erythrocytes (99.9%)
  • Leukocytes (<0.1%)
  • Thrombocytes (<0.1%)
16
Q

Functional Characteristics of RBCs

A
  • Large surface-to-volume ratio
    • Allows O2 to be bound & released quickly
  • RBCs can form stacks
    • Allows for easier flow through capillaries, a single stack can pass through vessels a cell wide
  • Flexibility
    • Allows them to squeeze into said capillaries
17
Q

How are RBCs produced?

A
  1. Prerythroblasts
  2. Erythroblasts
  3. After 4 days, Normoblasts
  4. Shed nucleus and become Reticulocyte
  5. After 2 days in bone marrow, reticulocytes enter bloodstream. After 24 hours in circulation, the reticulocytes complete their maturation & become indistinguishable from other mature RBCs.
18
Q

Properties of WBCs

A
  • Spend most of their time in loose & dense connective tissues (Reticulate tissue)
  • Bloodstream is used for primary transport
  • All WBCs can squeeze through many cells, & can adhere to the lining of veins & arteries
  • All WBCs are attracted to chemical stimuli
  • Live about 3-5 days on average
19
Q

5 WBCs

A
  1. Neutrophils
  2. Lymphocytes
  3. Monocytes
  4. Eosinophils
  5. Basophils
20
Q

Neutrophils

A
  • 50-70% of WBCs
  • Phagocytic: engulfs pathogens or debris in injured or infected tissue
  • Release cytotoxic enzymes
  • Move into tissues after several hours
  • 1st responders
21
Q

Eosinophils

A
  • 2-4% of WBCs
  • Phagocytic: engulf antibody-labeled materials
  • Release cytotoxic enzymes
  • Increase in allergic reactions & parasitic infections
  • Move into tissues after several hours
22
Q

Basophils

A
  • <1% of WBCs
  • Enter damaged tissues
  • Releases histamine & other chemicals that promote inflammation
  • Assit mast cells in producing inflammation
  • Most raise temperature in the body
23
Q

Monocytes

A
  • 2-8% of WBCs
  • Enter tissues & become macrophages
  • Phagocytic: engulfs pathogens & debris
  • Move into tissues in 1-2 days
24
Q

Lymphocytes

A
  • 20-30% of WBCs
  • Provide defense against specific pathogens or toxins
  • Circulate from blood tissues & back
  • 3 types
    • NK Cels
    • B Cells
    • T Cells
25
Q

Hemocytoblasts

A
  • Main stem cell for all blood
  • Lymphoid
  • Myoloid
26
Q

Lymphoid

A

Make Lymphocytes

27
Q

Myoloid

A

Makes everything but lymphocytes

28
Q

Where are WBCs produced?

A

Red Bone Marrow

29
Q

Platelets

A
  • Clump together & stick to damaged vessel walls
  • Release chemicals that stimulate blood clotting
  • Circulate for about 9-12 days before being consumed & replaced
30
Q

Blood Clotting

A
  • Technical term: Hemostasis
  • Stopping blood loss through the walls of damaged vessels
  • Establishes framework for tissue repairs
  • Traditionally divided into 3 phases:
    • Vascular
    • Platelet
    • Coagulation
  • However, it is still a complex event in which many things happen at once & all of them interact in some way
31
Q

Vascular Phase

A
  • Lasts for 30 minutes
  • The endothelial cells contract, exposing basal lamina
  • Endothelial cells release chemical factors & local hormones
  • Release endothelins which stimulate smooth muscle contraction & vascular spasms
  • Endothelins also stimulate cell division to aid in tissue repair
  • Endothelial tissue plasma membranes become sticky to provide partial seals & groundwork for platelets.
32
Q

Platelet Phase

A
  • Platelets attach to sticky endothelial surfaces, basal lamina, exposed collagen fibers & to each other
  • ADP is released by platelets to stimulate platelet aggregation & secretion
  • Chemicals that stimulate vascular spasms
  • Platelet factors are released to assist in blood clotting
  • Platelet derived growth factors (PDGF), a protein that promotes vessel repair
  • Calcium ions assist in platelet aggregation & the clotting process
33
Q

Coagulation Phase

A
  • Starts 30 seconds after or more after vessel damage
  • A complex series of events involving several clotting factors
  • The activation of one factor triggers the activation of another (Chain reaction or cascade)
  • Extrinsic & Intrinsic Pathways → Common Pathway
34
Q

Iron Deficiency Anemia

A
  • Lack of iron makes normal hemoglobin synthesis impossible
  • RBCs will be smaller than normal
  • Women need higher amount of iron in diet due to iron reserves being half that of typical men
35
Q

Sickle Cell Anemia

A
  • Due to a mutation in amino acid sequence, altering the shape of the beta chains in Hb
  • Fragile & easily damaged RBCs
  • More likely to clump in capillaries
  • Resistance to malaria
36
Q

Hemophilia

A
  • Genetic blood disorder that affects 80-90% of males
  • Caused by reduced production of a single clotting factor
  • Severity depends on reduction
  • In severe cases, minor contact can induce extensive bleeding, & it can occur in joints
37
Q

Malaria

A
  • Protozoan Plasmodium
  • Transmitted primarily by mosquitoes (Blood born)
  • Initially infects the liver, then RBCs
  • Dead RBCs can block blood vessels resulting in tissue death
    *
38
Q

Extrinsic Pathway

A

Damage to vessel

39
Q

Intrinsic Pathway

A

Platelets come together

40
Q

Common Pathway

A

Release Factor X (Fibrinogen → Fibrin)