Online Microbiology and Biology Notes
Yeast Artificial Chromosomes (YACs) Yeast artificial chromosomes (YACs) are genetically engineered chromosomes derived from the DNA of the yeast. It is a human-engineered DNA molecule used to clone DNA sequences in yeast cells. They are the products of a recombinant DNA cloning methodology to isolate and propagate very large segments of DNA in a yeast host. By inserting large fragments of …
Nucleus Definition The cell nucleus is a membrane-bound structure that contains the cell’s hereditary information and controls the cell’s growth and reproduction. It is the command center of a eukaryotic cell and is commonly the most prominent organelle in a cell accounting for about 10 percent of the cell’s volume. In general, a eukaryotic cell has only one nucleus. However, some eukaryotic cells are …
Read moreNucleus- Definition, Structure, Functions and Diagram
Chromosomes- Abnormalities and Disorders Chromosomes refer to any of the rod-shaped or threadlike DNA-containing structures of cellular organisms that are located in the nucleus of eukaryotes, are usually ring-shaped in prokaryotes (such as bacteria), and contain all or most of the genes of the organism. Simply put, it is a strand of DNA that is encoded with genes. Chromosomes are important because they …
Prokaryotic and Eukaryotic Chromosomes The genome of an organism encompasses all of the genes of that organism. Gene is a distinct sequence of nucleotides forming part of a chromosome, the order of which determines the order of monomers in a polypeptide or nucleic acid molecule. Thus a protein-coding gene is defined as a region of DNA that encodes a single …
Chromosome- Structure, Types and Functions In the nucleus of each cell, the DNA molecule is packaged into thread-like structures called chromosomes. Each chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure. Chromosomes were first described by Strasburger (1815), and the term ‘chromosome’ was first used by Waldeyer in 1888. They appear …