Dictionary > Zygosity


(genetics) The degree of similarity or the dissimilarity of the DNA sequences in specific coding segments, or genes, on the homologous chromosomes of a zygote, or fertilized egg
Chromosomes that occur in two sets are referred to as diploid (2n). Humans and many other organisms are diploid. This means that their somatic cell would have two copies of chromosomes. This is because the first set of chromosomes came from the mother whereas the second set came from the father. In humans, there are 46 chromosomes, which means 23 of these are inherited from the mother and the other 23 chromosomes are from the father. Each one from the first set of chromosomes would have a matching chromosome on the second set based on the sameness of their loci. The two chromosomes that have matching loci are referred to as homologous chromosomes. Homologous chromosomes may have the same or matching loci but their alleles may be similar or different. The degree of similarity or the dissimilarity of the DNA sequences (alleles) between homologous chromosome is referred to as zygosity.
A cell or an individual may be classified based on zygosity:

See also:

Related term(s):

You will also like...

Darwin's Finches - Natural Selection
Darwin and Natural Selection

This tutorial investigates the genetic diversity in more detail. It also delineates how certain alleles are favored over..

Animal Water Regulation

Animals adapt to their environment in aspects of anatomy, physiology, and behavior. This tutorial will help you understa..

Biosecurity and Biocontrol
Biosecurity and Biocontrol

This lesson explores the impact of biosecurity threats, and why they need to be identified and managed. Examples to incl..

Gibberellins and Gibberellic Acid
Gibberellins and Gibberellic Acid

This tutorial describes the role of gibberellin family in plants. Find out the effects of gibberellin on plant growth an..

Schematic diagram of bacterial lactose operon
Gene Action – Operon Hypothesis

Learn how the way genes control and determine every aspect of the body. This lesson uses lac operon as an example. ..


Oligodendrocyte and Schwann cell
The Central Nervous System

Myelin sheath is essential for a faster conductivity of signals. Know more about this feature of some neurons in the Cen..