Blood and immunity 1 Flashcards
What are the formed elements of the blood?
- RBC
- WBC
- Platelets (cell fragments)
T/F: blood is a connective tissue
True!
What makes blood unique among connective tissues?
The fact that is a fluid! (due to plasma)
What is the primary function of the blood?
Transportation and delivery of oxygen and nutrients to body cells as well as removal of wastes from body cells
What are some secondary functions of the blood?
- defense/protection
- regulation/maintenance of homeostasis
Where do most nutrients absorbed travel?
In the bloodstream directly to the liver where they are precessed and released back into the bloodstream for delivery to body cells
How does oxygen circulate in the body?
Oxygen we breath from the air diffuses into the blood which moves from the lungs to the heart which then pumps iut out to the rest of the body
How does blood remove carbon dioxide?
Blood brings CO2 to the lungs for exhalation from the body
How are various waste products removed from the body?
Transported in the blood to the kidneys and liver for excretion from the body in the form of urin or bile
What glands releases hormones into the blood stream to be carried to distant target cells?
Endocrine glands
Briefly explain some protective functions of the blood.
- WBCs protect from external threats such as disease causing bacteria that has entered the bloodstream
- Other WBCS seek out and destroy internal threats such as cells with mutated DNA or cells infected with viruses
- when damage to the vessels result in bleeding, platelets and certain poroteins interact to block the ruptured areas to protect from further blood loss
How does blood help maintain homeostasis?
- body temperature regulated via - feedback loop
- helps maintain chemical balance (pH), proteins and other compounds act as buffers
- regulate water content of body cells
What color is blood rich in oxygen in the lungs?
Bright red
What color is blood that has released oxygen in the tissues?
Darker, dusky red
Definition:
Pigment that changes color and varies with oxygen saturation levels
Hemoglobin
This is how pulse ox works to see how oxygen saturated your blood is
What incluences the viscosity of blood?
Presence of plasma proteins and formed elemenst in the blood
T/F: normal temp of blood is slightly lower than body temp
False! it is slightly higher (~38 degrees)
Body temp is 37 degrees
Why is the temp of blood higher than body temp?
Due to friction and resistance which produces heat
What is the average pH of blood?
7.4 (can range from 7.35-7.45)
Is blood slightly basic or acidic?
Slightly basic
What % of adult body weight does blood account for?
~8%
How much blood do males and femalse typically have?
Males: 5-6 litres
Females: 4-5 litres
This difference is primarily due to size
What percent of the blood is plasma and formed elements?
Plasma: 55%
Formed elements: 45%
What percent of plasma is water?
~91%
What percent of plasma is proteins? Other solutes?
Proteins ~7%
Other solutes ~2%
What is a normal hematocrit level? Anemic? Polycythemia?
Dehydration?
Normal - 45%
Anemia - 30%
Polycythemia - 70%
Dehydration - 70%
What are the 3 major groups of plasma proteins?
- albmin
- globulines
- fibrinogen
Definition:
Plasma without the clotting factors
Serum
Where is albumin created?
the liver
What is the most abundant plasma protein (~54% of plasma)?
Albumin
What is the role of albumin?
- functions as a binding protein for transporting lipid soluble hormones
- most significant contributer to osmotic pressure of blood
How does albumin help maintain osmotic pressure of blood?
Pulls water into the bloodstream from the tissues, helping maintain both the blood volume and blood pressure
Where are alpha and beta globulins produced?
liver
What do globulins do?
- transport iron, lipids, and fat-soluble vitamins
- aid albumin in contributing to osmotic pressure
What is the least abundant of the plasma proteins (~7% of the plasma proteins)?
fibrinogen
What is fibrinogen an essential component of?
Blood clotting process
What is the lifespand of a RBC?
~120 days
What is the average life span of most WBCs and platelets (with the exception of lymphocytes, which can live for months to years)?
Few hours to a few weeks
Definition:
Process of producing new blood cells and platelets
hemopoiesis
Definition:
Erythropoietin (EPO)
glycoprotein hormone secreted by the interstitial fibroblast cells of the kidneys and liver in response to low oxygen levels
What does EPO prompt?
production of erythrocytes in red bone marrow
What is blood doping?
Using synthetic EPO as a performance enhancing drug to increase RBC counts and subsequently increase oxygen delivery to tissues throughout the body
What is estimated to make up about 25% of the total cells in the body?
Erythrocytes
Review the control of erythropoiesis.
What is the legal way to blood dope?
Train at a higher altitude as the body will produce for RBC to compensate for the lack of oxygen being taken in, need to have a greater ability to move it around
What is the primary role of erythrocytes?
To pick up inhaled oxygen from the lungs and transport it to the body’s tissues. At the tissues tehy can pick up some carbon dioxide waste and trasnport it back to the lungs for exhalation.
How do erythrocytes increase their oxygen carrier capacity?
The protein hemoglobin. Each hemoglobin protein contains an iron ion which allows each molecule to bind 4 oxygen molecules.
How much hemoglobin do males and females have?
Males 13.5-17.5 g/dL
Females 11.5-15.5 g/dL
Do mean circulating erythropoietin levels differ between men and women?
No
T/F: when iron levels are equal, pre-menopausal women have mean hemoglobin levels approx. 12% lower than age and race matched men
True
Why do men and women have different RBC counts?
- testosterone increases EPO related production of RBC in males
- estrogen decreases the EPO related production of RBC in females
What is the shape of erythrocytes?
Biconcave disk
T/F: erythrocytes contain most organelles
Fales, they lack mosting including a nucleus for more space for the hemoglobin
The biconcave shape of RBCs lead to a —-% increase in surface area?
30
Definition:
oxyhemoglobin
when hemoglobin picks up O2 in the lungs which binds to the iron ions
Definition:
Deoxyhemoglobin
Bright red oxygenated hemoglobin that travels to the body tissues where it releases some of the oxygen molecules, becoming darker red
How does hemoglobin play a role in regulating blood flow and blood pressure via the release of nitric oxide?
NO causes vasodilation which imrpoves blood flow and enhances oxygen delivery
What is the role of carbonic anhydrase?
catalyzes the conversion of carbon dioxide and water to carbonic acid. carbonic acids transports 70+% of carbon dioxide in the plasma
How are worn-out RBCs removed?
By macrophages
Where are macrophages primarily located?
within the bone marrow, liver, and spleen
T/F: compoents of broken down RBC such as iron ions and heme groups are recycled
True
