Learning objective 4 (blood) Flashcards
Whats is in your blood
Plasma, red blood cells, white blood cells, platelets
What is the chemical composition of plasma?
It is made of mostly water and solutes like electrolytes(Na,K,ca), proteins, hormones, respiratory gases, nutrients, and fibrinogen which is a protein, antibodies which are globular proteins, non-protein nitrogenous substances (urea)
What happens when blood is spun in a centrifuge
It turns 2 colors one part being the plasma and one part called the formed substances (RBC WBC etc)
What are the formed elements?
Part of the blood is made up of red blood cells (erythrocytes), white blood cells (leukocytes), and platelets
What are Red Blood cells?
They don’t have a nucleus and they are biconcave cells because it allows for large surface area to volume and the cytoplasm is never too far from the cell membrane to allow for simple diffusion it is also made of hemoglobin which allows them to latch on to more oxygen.
How do red blood cells make hemoglobin if they don’t have a nucleus?
They have a nucleus when they are young cells but as they mature they lose their nucleus so they would have hemoglobin as baby red blood cells.
What are the two parts of hemoglobin?
They are made of 4 chains of amino acids and the heme group is made of iron
how many oxygen molecules can hemoglobin carry
It can carry up to 4 oxygen molecules
What can latch on to hemoglobin
Carbon dioxide, hydrogen, carbon monoxide
what bones make red blood cells
The red bone marrow in the flat thin bones like the pelvis, hips, skull, etc
What is erythropoiesis and where does it happen
It is the production of red blood cells in flat bones that have red bone marrow
What is the structure of a red blood cell and what does the structure help with
Red blood cells have a large surface area compared to the volume and have a biconcave shape with no nucleus. This helps it to absorb oxygen better and fit more oxygen into the cell
What is a hematopoietic stem cell?
It is the stem cell for blood that can become a red blood cell, white blood cell, or platelets
What is a reticulocyte
It is the last phase when making red blood cells where the cell has no nucleus but still has ribosomes and RNA to still make hemoglobin
Why is it important to maintain red blood cells
It’s important so that we have enough oxygen in the body and it can’t be too much so that we don’t have blood that is too thick causing the body to work harder to move it around the blood vessels
What is the feedback loop for red blood cells?
Nerve endings sense a drop in oxygen (hypoxia) so they send a message to the brain which tells the kidneys to release erythropoietin which stimulates red blood cells which increases red blood cell count
Why is too many red blood cells bad?
It makes the blood pressure and viscosity higher meaning the heart must work harder to push the blood
What are the 5 types of leukocytes
Neutrophils (50-70%), Eosinophils (2-4%), Basophils (0.5-1%), lymphocytes (25-45%), monocytes (3-8%)
Where are blood stem cells made
They are made in red bone marrow found abundantly in flat bones
What are macrophages
They are when monocytes squeeze out of the blood vessels and they are very aggressive cells and are really good at phagocytosis
What is hemostasis
Hemostasis is the prevention of blood loss
What are vascular spasms
This means the blood vessels are constricting
What are vascular spasms
This means the blood vessels are constricting
What is a proerythroblast
It is when the hematopoietic cell commits to being an erythrocyte
Describe the process of erythropoiesis?
The Hematopoietic cell is the blood stem cell it then changes into a proerythroblast which is when the cell has committed to being a red blood cell there are some stages after this that involve losing the nucleus eventually becoming the reticulocyte where there is still ribosomes and RNA to make hemoglobin it then matures into an erythrocyte.
Why is red blood cell regulated
It is regulated because if there isn’t enough of it fatigue will happen because there is not enough oxygen to help the cells produce enough energy
Describe red blood cell feedback loop
Receptors in the body sense decreased oxygen which sends a message to the control center of the brain. The brain then sends a message to the kidneys and liver which release erythropoietin which stimulates the red bone marrow to produce more RBC allowing oxygen-carrying capacity to increase
What causes decreased oxygen amounts in the body
low RBC count, low hemoglobin in the blood, decrease in oxygen in the environment
What are platelets
Platelets are a piece of a cell membrane that has granules in it which contain certain chemicals. Their sole purpose is to prevent blood loss
What are the mechanisms that work to prevent blood loss
Vascular spasms, platelet plug, and coagulation
What are the chemicals the platelets release
They produce ADP which causes more platelets to come to the area and causes them to be sticky, serotonin, and thromboxane A12
What are the two ways to get a prothrombin activator
The extrinsic and intrinsic pathways are how we make a prothrombin activator
What is the difference between extrinsic pathway and intrinsic pathway
The extrinsic pathway is one of the ways the body makes prothrombin activator and it doesn’t have all the ingredients it needs in the blood to make it so it needs tissue factor from cells rupturing while the intrinsic pathway has all its ingredients in the blood
What are the two main groups of white blood cells and what are their characteristics
Granulocytes which are normally very round and have nuclei connected by strands then there are agranulocytes which are normally don’t have a nucleus like granulocytes and don’t have those little dots in them
Explain the process of platelet formation
The platelet starts out by the hematopoietic cell turning into the megakaryoblast which matures then fragments of the cell fall off the cell containing granules.
What is primary active transport
This is when solutes are moved across the cell membrane against their electrochemical gradient so from low concentration to high concentration.
what are the functions of the blood?
It transportation, protection, regulation
