Blood is a very important part of maintaining homeostasis.
_______ is the bodies transport medium.
-It provides a means to transport oxygen, carbon dioxide, hormones, and nutrients
-it also contains most of the cells, proteins, and chemicals required to initiate and support resistance to disease.
______ _______ and ____ are also regulated by the blood.
Body temperature, pH
Because the blood has access to the entire body, ________ and _______ associated with the blood are not __________ disorders.
disorders, diseases, localized
True or False
Blood is not a connective tissue.
-All connective tissues share similar properties; they have cells and an extracellular matrix. Blood fits these parameters.
-The blood contains various types of cells and cell fragments, suspended in an extracellular matrix called plasma.
Together, ________, _______, and ________ provide a very efficient means of delivering nutrients and removing ______ to and from all areas of the body.
transportation, regulation, protection, wastes
True or False
Every cell in the body requires a continuous supply of oxygen and nutrients.
Restricting the blood supply to a tissue, even for a short period of time, will result in some amount of cellular death.
This is exactly what happens in the majority of heart attacks and strokes; the blood supplies to the heart and brain become blocked and the cells are injured or die.
What are the properties and physical characteristic of blood?
Viscosity: Thicker than water due to solutes, colloids, and suspended formed elements
Temperature: 380 C (100.40 F)
pH: slightly alkaline, 7.35-7.45
Volume: 4-6 liters depending on genderand body mass.
What are the two main components of blood?
-Formed elements (mostly cells)
the formed elements consist of ...
-Red blood cells (RBCs)
-White blood cells (WBCs)
-Account for about 45% of the total volume
The reason they are called formed elements is because of the platelets; they aren't cells; they are fragments of cells.
55% if total volume
a clear yellow liquid
92% water and 8% solute
The majority of the solute (7%of the 8%)are plasma proteins): albumins(54%), globulins(38%), fibrinogen(7%)
1% are miscellaneous solutes
There are many types
They have individual function but commonly act as carrier molecules
Collectively they contribute to the osmotic balance of the blood.
One of the important types of globulins
also known as immunoglobulins or antibodies.
These plasma proteins are produced in response to organic molecules that the body recognizes as foreign.
They serve as flags for the immune system, so it knows what needs to be destroyed.
The development of the formed elements of the blood.
Red bone marrow
Blood cells are formed in red bone marrow from pluripotent stem cells and mature in the bone marrow or lymphoid tissue (spleen, tonsils, lymph nodes, thymus etc.) under the influence of various cytokines.
In infants, all of the bones contain ______ ______ marrow and are actively making ______ elements.
red bone, formed.
As and individual matures, the ____ bone marrow in long bones is replaced with ____ bone marrow, which is mostly _______ tissue.
red, yellow, adipose
Proliferation and maturation of blood cells depend on specific _______.
Chemical signals form one group of cells to stimulate another
See. obj.4 p.702
What are examples of common cytokines and there effect on cells?
Erythropoietin (EPO): Increases number of early red blood cells in the bone marrow
Thrombopoietin (TPO): Increases the formation of platelets
Colony-stimulating factors (CSFs) and interleukins: Increases the production oand differentiation of white blood cells.
Red Blood cells
Are bi-concave discs
-gives high surface-to-volume ration
-able to squeeze through small spaces
Mature red cells do not have a nucleus
-Provides maximum cytoplasmic space
RBCs live about 120 days
Because they lack mitochondria, they don't us any of the oxygen they carry.
Why to red blood cells have a biconcave shape?
It gives them a high surface-to-volume ratio, thus allowing them to carry a great deal of oxygen in relation to their size
Think of this shape as a donut, but the hole in the middle doesn't go all the way through.
______ are required to squeeze through really small spaces, specifically _______ _______. As they pass through these small spaces, they become almost ______-____, but when they come out the other side, they revert back to their ________ shape.
RBCs, blood capillaries, torpedo-like, biconcave
The oxygen carrying molecule of the red blood cell.
If red blood cells are damaged, they are removed from circulation by...
phagocytic white blood cells,: the spleen, and the liver
True or false
There are approximately 280 million hemoglobin molecules in in each red blood cell.
Hemoglobin consist of two main components
a protein that is made up of four-polypeptide chains (two alpha chains and two beta chains)
Each polypeptide chain has a heme molecule bound to it
a ringed molecule with on iron (Fe2+) at the center
The iron atom is the binding site for oxygen (each Fe2+ can pick up on oxygen molecule at the lungs)
So if there are 280 million hemoglobin molecules in a red blood cell, and each has four hemes, each read blood cell can carry 1.1 billion oxygen atoms
True or False
At the lungs hemoglobin has a low affinity for oxygen.
At the lungs it has a high affinity for oxygen; it wants to pick it up and hold onto it.
At the tissue level it has a lower affinity for oxygen; it wants to let go of oxygen, thereby allowing it to diffuse into the cells.
True or False
Hemoglobin picks up a little bit of Co2 from the tissues to transport back to the lungs and be exhaled.