Apple Maggot Flies (Rhagoletis) Have Recently Evolved an “Apple Race” that has Distinctive

Apple maggot flies (Rhagoletis) have recently evolved an “apple race” that has distinctive alleles related to the timing of apple fruiting. These new alleles have changed the breeding time in the apple race, such that it no longer occurs during the same months of the year as the breeding season of hawthorne maggot flies. These […]

Darwin’s Theory – Fundamental Observations of Populations and Means of Natural Selection

Darwin’s Theory – Fundamental Observations of Populations and Means of Natural Selection     Darwin’s theory has the following five fundamental observations, from which 3 inferences can be drawn. Darwin’s observations: 1) All species have capacity for fertility so that their population would grow exponentially ,if all people which might be born cross on to […]

Why Transcription and Translation are Coupled in Prokaryotes

Coupling of transcription and translation means that ribosomes bind to the mRNA and protein synthesis (translation) begins while the mRNA is still being synthesized ( transcription ) Transcription and translation are coupled in prokaryotes because there is no nucleus to separate the processes of transcription and translation, when bacterial genes are transcribed, their transcripts can […]

How Bacteria can be Genetically Engineered to Produce a Human Protein?

HOW BACTERIA CAN BE GENETICALLY ENGINEERED TO PRODUCE A HUMAN PROTEIN: OVERVIEW: Bacteria is genetically modified to produce useful human proteins such as human growth hormone and human insulin. Genetic engineering can be used to create organisms that produce large amounts of useful substances – for example, bacteria can be engineered to produce human insulin […]


Define pollination. How does it differ from fertilisation? Pollination is defined as the transfer of pollen grains from the anthers to the stigma. Fertilisation is the fusion of the nuclei of two dissimilar male and female gametes. Pollination results in germination of pollen grains, formation of pollen tubes and entry of pollen tube inside the […]