What is Biology and What Are the Unifying Themes?


The science of biology is the study of life. While its scope is broad, it has several unifying themes. For example, all organisms contain cells and process genetic information encoded in genes, which is then passed down to future generations. Similarly, animals and plants also process the information encoded in their DNA. So, what is biology, and what are the unifying themes? Below we explore some of the major topics in biology.


Parasitic biology involves understanding the biology of parasites in humans and animals. To understand the biology of parasites, scientists must first understand how they live and behave. There are many ways to study parasites. In vitro assays are one of these methods. They provide researchers with access to various strains and stages of parasite differentiation.

Most parasites are multicellular organisms that live on a host. Depending on the type, they can be harmless or harmful to their host. Parasites come in three main types: ectoparasites, endoparasites, and helminths. Ectoparasites live on the skin and are typically not harmful, while endoparasites can live inside the host body, including its muscles, bloodstream, and digestive system.


Parhomologous in biology is a term that refers to two similar genetic regions. For example, human and dog DNA is homologous if they have the same coding sequences. However, this doesn’t necessarily mean they are identical, as they can have slightly different sequences.

The opposite of homology is nonhomology, the term used for similar features and conditions in two or more organisms but does not derive from the same immediate common ancestor. This term is sometimes used instead of homology because it can be slightly ambiguous. This term is usually used to describe morphological or functional similarities in two or more organisms, but it’s not as precise as it used to be.


Parthenogenetic biology is the study of how the genetic material of an organism is transferred from one parent to the offspring. Unlike sexual reproduction, parthenogenesis does not require the creation of new gene combinations. This characteristic may put some parthenogenetic animals at a competitive disadvantage compared to sexually reproducing animals. Sexual reproduction involves combining gametes from two parents, a process that takes time and may produce few offspring. On the other hand, parthenogenetic organisms can reproduce much faster and produce more offspring.

In parthenogenesis, the egg cell produces an embryo without undergoing fertilization. It is the normal method of reproduction for many lower organisms. However, it does not produce viable mammalian offspring. Parthenogenetic development can take various routes depending on the condition of meiosis. In most cases, the offspring are entirely female.


Circadian rhythms in organisms depend on the daily cycle of light and dark. Photoperiodic biology studies these rhythms and how these rhythms are influenced by daily cycles in light and darkness. Since the idea was proposed over 70 years ago, various physiological experiments have corroborated the theory. However, the molecular basis for these clocks has remained obscure, especially in insects. However, our understanding of these biological clocks is advancing rapidly.


Theoretical biology, also known as biomathematics, uses mathematical and abstract concepts to study living organisms. Biological systems are modelled using abstract representations of their physical characteristics. This helps scientists to understand the complexity of these systems. Theoretical biology can also be applied to the design of experimental procedures.

Theoretical biologists use the principles of biology to develop concepts that can simplify and explain biological phenomena. This type of biology aims to develop concepts and theories to explain complex phenomena and develop greater predictability.


The ecology study encompasses five broad levels, from the individual organism to a community of different species. The individual organism can be anything from a protist to an elephant. The organism’s habitat is the area where that species can live and thrive. The community is made up of similar species that share a common environment.

The main goal of ecology is to understand better how living things interact with their environments. Different living things are found in different environments, from coral reefs to our backyards. Those differences are due to the interactions between different organisms and their surroundings. For example, mould is much more likely to grow on a piece of bread than on a rock since it requires nutrients.