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Cytotoxic T cell receptors, activation, proliferation, differentiation & action

By: HWC, Views: 6981

• Most cells which have CD8 on their surface become cytotoxic T cells (Tc cells). • CD8 T cells recognize a foreign antigen when it is presented in conjunction with the protein, MHC-I. • Nearly all nucleated cells in the body express MHC-I molecules. • T cells that recognize self-pe...

Immune responses Animation

By: HWC, Views: 3512

Overview of interactions in antibody-mediated and cell-mediated immunity Animation The antibody mediated immune response begins when a naive B cell encounters antigens from a pathogen, such as a bacterium. The B cell binds, processes, and displays this antigen. It is now an antigen-presenti...

Vascular tissues in a corn stem and a buttercup root

By: HWC, Views: 1134

Vascular tissues in a corn stem and a buttercup root. The cells that make up each tissue. Xylem conducts water and dissolved ions. It also helps mechanically support a plant. The cells, called vessel members and tracheids, are dead at maturity. Their lignified walls interconnect and serve as p...

Type of Cell Junctions - Desmosome, Hemidesmosomes and Gap Junctions

By: HWC, Views: 6984

Cell Junctions: Cell junctions are found in some multi-cellular organisms. They exist of complexes and are found between cells and between cells and other structures. The junctions provide a way for cells to connect and exchange signals. What are tight junctions, desmosomes, and gap junctions...

Hormonal feedback loop components

By: HWC, Views: 6770

The endocrine system maintains many body conditions within normal limits with feedback loops. Each endocrine feedback loop maintains homeostasis using the following components: ■ Stimulus - a change in a body condition. ■ Production cell - an endocrine cell that produces a hormone after b...

HIV Infection: Viral life cycle

By: HWC, Views: 6002

The series of steps that HIV follows to multiply in the body. The process begins when HIV encounters a CD4 cell. The seven steps in the HIV life cycle are: 1) binding; 2) fusion; 3) reverse transcription; 4) integration; 5) replication; 6) assembly; and 7) budding. Many viruses f...

Leukemia

By: Administrator, Views: 10155

Leukemia is a type of cancer that affects the blood and bone marrow. Leukemia begins in a cell in the bone marrow. The cell undergoes a change and becomes a type of leukemia cell. Once the marrow cell undergoes a leukemic change, the leukemia cells may grow and survive better than normal cells.

Major Elements in Biological Molecules: Carbohydrates

By: HWC, Views: 6192

Carbohydrates include simple sugars (monosaccharides) as well as large polymers (polysaccharides). Glucose is a hexose, a sugar composed of six carbon atoms, usually found in ring form. A starch macromolecule is a polysaccharide composed of thousands of glucose units. Glucose molecules can be ...

Introduction to Sickle Cell Anemia

By: Administrator, Views: 10071

Sickle cell anemia (sickle cell disease) is a disorder of the blood caused by an inherited abnormal hemoglobin (the oxygen-carrying protein within the red blood cells). The abnormal hemoglobin causes distorted (sickled appearing under a microscope) red blood cells.