Blood And Blood Vessels Flashcards
Is blood a type of connective tissue? Explain.
Yes, blood is a specialized type of connective tissue that move through the circulatory system propelled by the contraction of the heart
What are some functions of blood?
- delivery of oxygen and nutrient cells
- transports CO2 and waste away from cells
- delivery of hormones and maintains homeostasis
What are the three type of blood cells?
Erythrocytes—RBCs
Leukocytes—WBCs
Thrombocytes—platelets
What is Plasma?
Extra cellular protein rich fluid that consists of:
- water, proteins, electrolytes, nutrients, and respiratory gases and waste
- contains SERUM
What is serum of the plasma?
This is the fluid portion of blood after blood has clotted. Same make up of plasma except clotting proteins have been used up
What are Erythrocytes? Explain these and give detail of their structure life span and importance of this.
These are red blood cells. They are full of hemoglobin which is a specific protein that transports CO2 and O2.
- structure is a biconcave disk which allows for increased surface area of gas exchange and folding
- lifespan is 120 days—> membrane proteins critical to protection of membrane and RBC survival
What are Leukocytes? What two groups can these be broken up into?
Leukocytes are white blood cells that leave the blood and migrate to tissue to perform specific function (usually immune)
Two groups:
- Granulocytes
- Agranulocytes
Explain the WBC type granulocyte. Provide three examples of granulocytes and their function.
Granulocytes contain secondary granules that have specific functions and primary granules that are lysosomes.
Three examples of granulocytes:
- Neutrophil (polymorphonuclear leukocyte PMNs)
- Eosinophils
- Basophils
Explain the WBC type Agranulocytes. Provide two examples and their function.
These lack specific granules but contain nonspecific granules
Examples:
- Lymphocytes
- Monocytes
Provide a brief description of neutrophils. What is a key factor that these have in the body?
These are PMNs, they are the most prevalent type of Granulocyte. Roughly 50-70% of circulating WBCS are these.
-these are phagocytic and are the first line of defence against bacteria response to necrosis
Provide a brief description of Eosinophils. What is a key factor to this WBC? What two components do these contain?
Roughly 1.4% of circulating WBC. These are bi-lobed and phagocytic.
- these are important in inflammatory responses against allergies as they secrete histaminase and phagocytize antigens
- the granules contain major basic proteins (MBP) and eosinophillic peroxidase (EPO) which kill parasites
Provide a brief description of basophils. What is a key factor to this WBC? What two components do these contain?
These are less than 1% of circulating WBC.
This is an important cell as it is associated with type 1 hypersensitivity reactions. Which is basically immediate hypersensitivity reactions and leads to anaphylaxis.
- granules contain histamines (vasodilator and increase of vascular)
- granules contain heparin (anticoagulant)
Provide a brief description of lymphocytes. What is a key factor to this WBC? What three components do these contain?
These are the most numerous agranulocyte (which is roughly 20-40% of circulating WBC)
The main function of these are to protect and respond to the immune system. These have a long lifespan.
Three main components:
- T lymphocytes (T-Cells) involved with cell mediated immunity
- T helper cell is CD4
- T cytotoxic cell is CD8 - B lymphocytes (B cells) involved in humoral immunity (antibody production)
- Natural Killer cells which destroy unhealthy host cells infected with bacteria
Provide a brief description of Monocytes. What is a key factor to this WBC? What happens when the leave the vasculature?
Monocytes are 2.8% WBC circulatio. Largest WBC. These are indented kidney beans or C shaped nucleus.
- they are phagocytic and the garbage picker upper of the body. They clean up debris.
- these function as an antigen presenting cell (APC) and produce inflammatory mediators.
When they leave the vasculature they transform into macrophages
Provide a brief description of Thrombocytes. What is a key factor to this WBC, what are they derived from? What two components do these contain?
These are membrane bound cell fragments that are derived from megakaryocytes in the bone marrow.
These contain two of the following:
- Hyalomeres—> lighter stained peripheral zone
- granulomere—> darker stained central zone rich in granules which contain ADP ATP and serotonin.
What are the primary and secondary factors to platelet function?
The key factors in these WBC is that they function in controlling blood loss (adhesion and aggregation at primary hemostasis)
as well as as blood coagulation (secondary hemostasis)
What is hemopoiesis (hematopoiesis)? Where does it occur? What are blood cells derived from?
This is the formation of new blood cells in the bone marrow that’s include erythropoiesis, thrombopoiesis, and leukopoiesis.
Blood cells are derived from pluriopotential stem cells (or hemopoietic stem cells)
What is colony stimulating factors in blood cells?
This is the growth factor that initiates the differentiation of the pluropotential stem cells into colony forming units (CFU)
What two differentiations come from Colony Stimulating Factor?
Myeloid line and lymphoid line.
What kind of capillaries does bone marrow contain?
Sinusoidal capillaries which allows for easier release of mature blood cells into peripheral circulation
What are megakaryocytes?
These are large multinucleated cells, cytoplasmic processes pinch off and release as platelets to peripheral circulation
What does the circulatory system include?
This includes lymphatic and CV systems
What does the CV system include?
Heart
Arteries
Capillaries
Veins
What are the two major divisions of the CV system? What is the third division?
- Pulmonary circulation
- Systemic circulation
- Lymphatic vascular system
What is the function of the following:
Heart
Arteries
Capillaries
Veins
Heart—> propels blood through system
Arteries—> vessels from the heart carrying oxygenated blood to the tissues
Capillaries—> smallest vessel which are sites of O2 and CO2 and exchange
Veins—> carry deoxygenated blood back to the heart
What is the function of the three division of the CV system?
Pulmonary—> conveys blood from heart to lungs and lungs to heart
Systemic—> conveys blood from heart to tissue and tissue to heart
Lymphatic—> carries lymph fluid to vessels that connect to CV system and act as immune distributor (such as lymphocytes and antibodies)
When the body is at rest, ___% of the blood moves through _____ circulation. Roughly __% move through the _____ circulation and ___% move through the ____
When the body is at rest, 70% of the blood moves through systemic circulation. Roughly 18% move through the pulmonary circulation and 12% move through the heart
Explain the 4 chambers of the heart: Right atrium Left atrium Right ventricle Left ventricle
Right atrium—> receives blood from the body
Left atrium —> receives blood from the pulmonary veins
Right ventricle —> propels blood to the pulmonary circulation
Left ventricle —>propels blood to the systemic circulation
What are the three major layers of the heart?
- Endocardium
- Myocardium
- Epicardium
What is the endocardium, what does it encapsulate?
Endocardium is the most internal layer of the heart. Can be divided into the following:
- endothelium—> supports connective tissue
- myoelastic layer—> smooth muscle and connective tissue
- sub-endothelial layer—> connective tissue containing purkinje fibres (which help in conducting heart rate)
What is the myocardium, what does it encapsulate?
This is the thickest layer of the heart that contains cardiac muscles
What is the epicardium, what does it encapsulate?
The epicardium is a simple squamous mesothelium layer that supports connective tissue and connects to the pericardium (surrounding the heart)
What are the three layers of the vascular wall that comprise arteries and veins?
- Tunica intima
- Tunica media
- Tunica Adventita
Provide a brief description of the tunica intima and it’s (3) important functions/parts
Innermost layer that consists of three parts:
- single layer of simple squamous epithelial cells (endothelium) which functions as permeability barrier and produces factors that stop blood clotting sand inflammation
- basal lamina
- sub endothelial layer which contains the internal elastic lamina to allow for diffusion of suntan cues deeper into vessel wall
Provide a brief description of the tunica media and it’s important functions/parts
Comprised of smooth muscle cells spread out with various amount of elastin, reticular and collagen.
-this is the thickest layer in arteries and arterioles.
An external elastic lamina membrane separates tunica media from adventita
Provide a brief description of the tunica adventitia and it’s (3) important functions/parts
This is the outermost connective layer, consists of collagen and elastin.
-this is the thickest layer in veins and venules.
Within the tunica adventitia the ____ ____ are smaller blood vessels that supply blood to vascular wall
In contraction, the ___ ____ is an autonomic nerve that controls contraction of smooth muscle in vessel walls
Vasa vasorum
Nervi vasorum
True or false: explain
Blood vessels do not branch and remain their size and type of vasculature
False:
Blood vessels branch frequently and undergo gradual transition into different types of vessels that make up the vasculature
Explain the physiological function and structure of large arteries elastic arteries. What are some examples?
These have thick tunic media with multiple sheets of elastic lamellae and alternating smooth muscle
- primary function as conducting arteries (carries blood to smaller arteries)
- examples include pulmonary arteries, common carotid, subclavian, and common iliac
Explain the physiological function and structure of medium arteries and muscular arteries. What are some examples?
Tunica media has smooth muscle with less elastic fibre
-primarily functions has distributing arteries (carries blood to organs)
Functions as well as regulating blood pressure by contraction and relaxation of smooth muscle
Explain the physiological function and structure of small arteries and arterioles. What are some examples?
Small arteries have 3-10 layers of smooth muscle in tunica media
-Arterioles have 1-2 layer of smooth muscles in tunica media
Arterioles control blood flow to capillary network by contraction of smooth muscles
Explain the physiological function and structure of capillaries. What are some examples?
Smallest blood vessel and smaller than RBCs. Have thin wall to allow gas exchange and waste product.
- surrounded by pericytes (perivascular contractile cells that facilities blood flow)
- involved in micro vascular remodeling and repair
What are the three histological types of capillaries and their functions?
- Continuous capillaries—> most common, tight junction between endothelial cells so that all exchange must occur through the cell
- Fenestrated capillaries—> have small pours called fenestrations through the cell but basement membrane is continuous. Allows for more extensive exchange
- Discontinuous capillaries (sinusoids, sinusoidal capillaries)—> fenestration through endothelial cells allow for discontinuous basement exchange of molecules. Prominent in liver bone marrow and spleen
What are venules? What is the purpose of post capillary venules and what do they contain?
Post capillary venules collect blood from capillary networks and contain pericytes.
These branch into slightly larger venules that are established into a tunica media of 2-3 layers of smooth muscle that is scattered
What is the function of small and medium veins?
Blood entering veins under low pressure move blood to heart by contraction of smooth muscle in tunica media.
Small veins—> collect blood from venules which have 2-3 layers of smooth muscle in tunica media
Medium veins—> carry blood to larger veins and important features found in these are valves. (Which are thin folds of tunica intima that project across a lumen that keeps venous return directed to heart)
What is the function of large veins? Where are they found?
- return blood to heart and have developed intima which show an internal elastic lamina
- these are relatively thin tunica media
- the tunica adventitia is a very thick part and contains longitudinal bundles of smooth muscle
- found in inferior and superior vena cava, as well as hepatic portal veins and subclavian veins
What are lymphatic vessels? Where are they found?
These remove substance and fluid from extra cellular spaces of connective tissue=lymph
- convey lymph fluids from tissue to blood and has very thin endothelial cell walls with space in between
- these are found in the immune system
