Q1. The cell walls if bacteria, fungi and plant cells and an extracellular matrix of animal cells are all external to the plasma membrane. Which is the characteristic of all these extracellular structures? Q2. In each dihybrid cross, the phenotype ratio of individuals with black hair and brown eyes, black […]

Q1. Though only a small amount of nutrients are absorbed, precise water absorption is an important function of the? Q2. The many species of tree frogs that inhabit forests in the eastern U.S. maintain their genetic isolation from other species by several mechanisms, including “singing” slightly different songs. Which kind […]

Question: Shigella flexneri is an intracellular pathogen closely related to E. coli and S. typhimurium. Some experiments have shown that oxygen controls expression of some virulence factors in this organism. Assume that you have a S. flexneri gene, oxyA, that appears to code for a virulence factor and is only expressed […]

Sexual reproduction occurs in the bread mould (Neurospora crassa) when two haploid strains of different mating types come into contact with each other. The haploid cells fuse to form a diploid cell, which then undergoes meiosis to produce haploid spores. The spores are dispersed and grow into new fungal colonies […]