10 topics with brief reviews: definitions, key facts, and class questions.
Blood is a specialized liquid connective tissue that performs transport, protective, and homeostatic functions. In this section, we examine its histological structure straight to the point, from cellular composition to molecular features.
You will study the composition of blood plasma and get a detailed look at all formed elements. We will cover erythrocyte morphology, hemoglobin structure, and blood group antigen systems. A separate block is dedicated to immune cells: granulocytes (neutrophils, eosinophils, basophils) and agranulocytes (lymphocytes, monocytes, and their tissue forms — macrophages).
Practical classes and colloquia most commonly require you to know the normal leukocyte differential, be able to visually distinguish cells on a smear by nuclear shape and specific granulation staining, and understand the logic of the macrophage system. The materials in this section will help you quickly structure your knowledge and answer with confidence at the microscope.
Serum is plasma from which fibrinogen has been removed during the natural blood clotting process.
Why is a lighter central area visible in erythrocytes under light microscopy?
This is an optical effect caused by the biconcave disc shape (discocyte). The central part of the cell is significantly thinner, so it binds less dye and appears lighter.
Which chemical bond in hemoglobin is responsible for gas exchange?
The reversible binding of oxygen or carbon dioxide is mediated by the sixth coordination bond of the divalent iron atom ($Fe^{2+}$).
Can mature neutrophils divide?
No. All forms circulating in the blood (including young and band forms) are terminally differentiated cells and lack mitotic activity.
What is basophil metachromasia and what causes it?
Metachromasia is the ability of granules to change the original color of a dye (for example, toluidine blue produces a purple or red coloration). This phenomenon is due to the presence of heparin in the granules.
Master the entire topic in the "Histology" course
This is a summary. The course covers everything tested in classes and exams.
3,485 pages of study guides for all topics
Assignments and quizzes after every topic — just like in a colloquium