Cardiovascular Part I: Blood Flashcards
2 parts of the Circulatory System
composed of the cardiovascular system (2-way circulation of blood) and the lymphatic system (one-way transport of lymph)
3 Parts of the Cardiovascular System
- blood
- heart
- blood vessels
4 Components of the Lymphatic Systems
- lymphatic vessels
- lymphocytes
- lymphoid tissue
- lymphoid organs
How is blood a connective tissue?
It consists of:
- cells (erythrocytes and leukocytes)
- fibers (fibrin strands formed by clotting factors)
- ground substance (plasma)
Functions of blood
- carries respiratory gases, nutrients and hormones
- regulates body temperature
Classification of Blood Components
- living cells - “formed elements”
- non-living matrix - “plasma”
Hematocrit
- packed cell volume
- a volume percentage of erythrocytes
- 47 +/- 5% in males
- 42 +/- 5% in females
Blood Plasma
- straw-colored, sticky fluid portion of blood
- 90% water, makes up 55% of blood volume
- contains ions, gases, nutrients, wastes and proteins
- three main proteins:
- albumin
- globulins
- fibrinogen
albumin
- smallest, most abundant plasma protein
- contributes to viscosity and **osmolarity **
- transports solutes and buffers pH (7.34 - 7.45)
Fibrinogen
- soluble fibrin precursor
- fibrin forms sticky network for clotting
Globulins
- contributes to immune function
- known as antibodies
serum
- plasma minus its clotting factors (formed elements)
What is a clot?
- platelets trapped in a network of fibrin
3 types of formed elements in blood
Formed elements = cells
- erythrocytes (red, 99%)
- leukocytes (white)
- thrombocytes (platelets)
numerous large, lightly stained cells here:
erythrocytes
- 4-6 million/mm3
- originate in red marrow
- main function is O2 and CO2 transport
anatomy:
- anucleate
- no organelles
- biconcave disks
- packed with hemoglobin
How long do erythrocytes live and where do they go to die?
about 100-120 days; the liver and spleen
- short-lived due to their lack of organelles, so can’t repair themselves, etc.
Why are erythrocytes biconcave?
to increase their surface area for O2 absorption and distribution
What molecule is this? What are its two main components? What is its function?
Hemoglobin;
Four globins each with a heme pigment;
to transport O2 by its tendency to bind to the Fe2+ on each heme
the general term for the kind cell shown here darkly stained
White Blood Cell (AKA Leukocyte)
- 4,800-11,000/mm3
- carry out immunological functions
What is the process of WBCs leaving blood capillaries to attack pathogens called?
Diapedesis
Types of Leukocytes (2 main categories; 5 total cell types)
- Granulocytes - (cytoplasmic granules & lobed nuclei)
- Neutrophils
- Eosinophils
- Basophils
- Agranulocytes - (no granules & unlobed nuclei)
- Lymphocytes
- Monocytes
What kind of WBCs are these?
Neutrophils (granulocyte)
- most common WBC (60%)
- 2-6 lobes per nuclei attached by chromatin strands
- active bacterial phagocytes
What kind of WBC is this?
eosinophil (granulocyte)
- 1-4% of WBCs
- bilobed nucleus
- increased in allergic response
- phagocytize allergens bound to antibodies
- kill parasitic worms
What kind of WBC is this?
basophil (granulocyte)
- very rare
- usually two lobes per nucleus
- heavily grainy cytoplasmic staining
- contain and release histamine to initiate inflammation
What kind of WBC is this? What are the two types of it and their functions?
lymphocyte ( agranulocyte)
- 20-45% of WBCs
- large, round nucleus almost fills cell (cytoplasm just a rim around the nucleus)
two types:
- B-lymphocytes (bone marrow) - produce antibodies, recognize and mark cells for destruction by macrophages
- T-lymphocytes (thymus) - target alien cells; reject transplants; kill virus-infected cells and some cancers; are cytotoxic
What kind of WBC is this?
monocyte (agranulocyte)
- 4-8% of WBCs
- horseshoe/kidney-shaped nucleus
- active phagocytes
- become macrophages when in tissues
- largest WBC
DLC (Differential Leukocyte Count)
Neutrophil - 60%
Eosinophil - 1-4%
Basophil -
Lymphocytes - 20-45%
Monocytes - 4-8%
thrombocytes (aka platelets)
- fragments of megakaryocytes
- membrane-bound cytoplasm fragments without nuclei
- essential to clotting; adhere to blood vessel tears
What is the name for blood cell formation?
hematopoiesis
- 100 billion cells each day
Bone Marrow and Hematopoiesis
(which color of marrow?)
- red marrow
- contains immature erythrocytes
- yellow marrow is dormant
What parent cell do all blood cells come from?
Hemocytoblasts or Blood Stem Cells
AKA pluripotential hematopoietic stem cell
- differentiate into:
- lymphoid stem cells - lymphocytes
- myeloid stem cells - all other blood cells (RBC, WBC, platelets)
What cells come from lymphoid stem cells?
Lymphocytes only
What cells come from myeloid stem cells?
