Which set of chromatids illustrates the result of a single crossover of the homologous chromosomes?

_tissues respond quickly to outside stimuli a) epithelia b)nervous c)muscular d)muscular and nervous

According to theories of how life began, how did early organic molecules begin to separate from the outside world? a: specialized enzymes were required b: chains of amino acids created a barrier c: formation of microspheres or vesicles d: rna catalyzed the formation of membranes

Add solid urea to a beaker of water. the beaker gets very cold. is δh favorable or