Cellular Components Flashcards
What are the 2 main components of blood?
- Formed elements
2. Plasma
Blood is a special type of connective tissue. What is the matrix of this tissue known as?
Plasma
The formed elements are classified into 3 main categories. What are they?
- Erythrocytes
- Leukocytes
- Platelets
Mention the relative amounts of formed elements and plasma.
45% and 55%
What are the characteristics of plasma?
Yellow color
Homogeneous
What is the major component of plasma? What is the composition?
Water
90%
Besides the 90% of water in the plasma, what occupies the remaining 10%?
Various solutes dissolved in the water component of plasma
What percentage of these solutes do proteins bear?
80%
Name 3 main plasma proteins.
Albumin
Globulins
Fibrinogen
When proteins are excluded, the plasma is occupied by several other types of solutes. What is their percentage? What are they?
20%
Various nutrients Inorganic salts Electrolytes Nitrogenous compounds Hormones Enzymes Dissolved gases
What are some nutrients found in plasma?
Glucose
Amino acids
Lipids
What are the dissolved gases in plasma?
Oxygen
Nitrogen
Carbon dioxide
What are the nitrogenous compounds found in plasma?
Urea
Creatinine
What are the most numerous cells in blood?
Erythrocytes
Describe the structure of a mature RBC.
Circular, biconcave disc shaped.
Does not have a nucleus.
Cytoplasm has no cellular organelles.
What is the diameter of a living erythrocyte?
7.5 μm
What is the thickness of an erythrocyte?
- 6 μm at the periphery (rim)
0. 8 μm at the central region
How are erythrocytes seen in blood smears stained by the Wright stain?
Circular bodies which stain pinkish color
In which part of the body do RBCs develop as true cells?
Bone marrow
What modifications are made to RBCs in bone marrow, before they enter the blood?
Extrude their nucleus and lose various cellular organelles (including the mitochondria).
How do erythrocytes generate energy?
By anaerobic glycolysis
What is the main content of the cytoplasm of an erythrocyte?
Iron-containing metalloprotein Hemoglobin
Hemoglobin binds reversibly with oxygen and carbon dioxide separately to form;
Oxyhemoglobin and Carbaminohemoglobin
Why do RBCs give a reddish tinge to circulating blood?
Because the hemoglobin in the cytoplasm of the erythrocyte turns red when it binds to oxygen.
How does the biconcave shape of erythrocytes facilitate the gaseous exchange?
By increasing the surface area of the cells and by bringing the plasma membrane of the cell close to the hemoglobin molecules present in the cytoplasm
How are erythrocytes capable of considerable distortion in shape?
They have a very pliable and elastic body due to which they have the capability to fold themselves to pass through the small capillaries that have lesser calíber than their own diameter.
The RBCs are enveloped by a specialized cell membrane. State its functions.
- imparts flexibility to the cells
- prevents adhesion of erythrocytes to the endothelium of blood vessels and to other cells.
- determines the antigenic properties of the erythrocytes (forms the basis of blood grouping)
What is the average life span of erythrocytes?
120 days