In the 1950s, christian anfinsen demonstrated the renaturation of the protein ribonuclease (rnase) in vitro. after reduction and the addition of urea, the protein was in an unfolded state. after removing the urea and then the reducing agent, the protein oxidized and refolded, with greater than 90% activity. if reducing agent removal occurs before removing the urea, the protein showed less than 5% activity. why does synthetically produced rnase refold incorrectly if the reducing agent is removed before urea removal? contaminants in the rnase preparation would form covalent bonds with the protein, preventing reactivation. urea would participate in weak bonding interactions with rnase, preventing oxidation of cys. disulfide bonds are not positioned correctly unless weak bonding interactions are present. the protein would not fully denature.

Astudent conducts an experiment to determine how the amount of water given to a plant affects it growth what is the dependent variable for this experiment

Approximately 90% of all cases of polycystic kidney disease are inherited in an autosomal dominant fashion. the disease is typically related to mutations to genes (pkd1 and pkd2). pkd genes can be found on chromosome 16. the disease occurs in approximately 1: 800 to 1: 1000 people. here is a hypothetical example. the dominant allele d will cause the development of pkd. the recessive allele is known as d. what genotypes would correspond to suffering from pkd? dd, dd what genotypes would correspond to being normal (not suffering from pkd)? dd consider that 1: 1,000 people have pkd in your population of 325million. consider that pkd is inherited in an autosomal dominant fashion. show you math for all of the following questions: what is the genotypic frequency for dd? what is the genotypic frequency for dd? what is the genotypic frequency for dd? what is p? what is q? how many people in your population would have pkd?

Food webs - transferring energy and matter from one level to another. here you see four food webs. one or more are incorrect. which food web(s) show the correct sequence of organisms, from start to top level consumer? a) a b) d c) c d) a and d