Used blood leaves the breasts through the veins and is pumped back to the heart and lungs to be refreshed. Lymph must also be refreshed and recycled. Lymph drains away from your breasts through the lymphatic system, which is made up of lymphatic channels and lymph nodes.
exists and is an alternate of . Chromosomes are located in the nucleus of a cell in eukaryotes. In prokaryotes (which lack a cell nucleus) chromosomes are circular in shape usually found attached to the plasmid membrane. Smaller circular DNA known as plasmids are also found in the prokaryotic cells and are thought of as smaller versions of chromosomes.
Key Concepts: In eukaryotic cells, genes are located in chromosomes in the cell nucleus. Before the DNA has been replicated, a chromosome consists of a single very long DNA double helix that is highly coiled and folded by proteins. Five major types of histone proteins, all of them highly basic, neutralise much of the DNA's negative charge and package the DNA into nucleosomes and 30ânm fibres.