769238
Description
Flashcards by sophietevans, updated more than 1 year ago
|
Created by sophietevans
over 10 years ago
|
|
| Question | Answer |
| Where do the leukocytes populate? | The lymphoid organs, the blood, and the lymph. |
| What is are the main divisions of leukocytes? | They are divided into antigen-specific lymphocytes (which are diverse, specific, capable of memory and self-nonself recognition) and other leukocytes which can be involved in antigen-presenting cells, participating as effector cells in the elimination of antigen by phagocytosis, the secretion of immune effector molecules, and more. |
| What proportion of bone marrow cells are haematopoietic stem cells? | ~1%, fewer than 1 per (5x10^4) |
| Why are haematopoietic stem cells pluripotent rather than totipotent? | They are limited in what they can differentiate into: lymphoid and myeloid progenitors, which can then further differentiate into different blood cells. |
| Which cells can myeloid progenitors differentiate into? | Erythrocytes, granulocytes (neutrophils, eosinophils, and basophils), platelets, monocytes, and dendritic cells. |
| Which cells can lymphoid progenitors differentiate into? | Lymphocytes, natural killer cells, and dendritic cells. |
| There are two phenotypes of dendritic cells: CD8α+ and CD8α-. Which progenitors are these differentiated from? | |
| Describe the differentiation possibilities for progenitor cells. | Progenitor cells have lost the capacity for self-renewal and are committed to a particular cell lineage. |
| Stromal cells, where haematopoietic stem cells and their descendants differentiate, grow, and mature, consist of which cell types? | Fat cells, endothelial cells, fibroblasts, and macrophages. |
| How do stromal cells influence the differentiation of haematopoietic stem cells? | They provide a haematopoietic-inducing microenvironment, consisting of a cellular matrix and factors that promote growth and differentiation. Many of these are soluble agents that can diffuse to their target cells, whereas others are membrane-bound molecules on the surface of stromal cells that require cell-to-cell contact between the responding cells and the stromal cells. |
Want to create your own Flashcards for free with GoConqr? Learn more.