In the 1950s, christian anfinsen demonstrated the renaturation of the protein ribonuclease (rnase) in vitro. after reduction (to reduce the disulfide links) and the addition of urea (to denature the protein), the protein was in an unfolded state. after removing the urea and the reducing agent, the protein refolded, with greater than 90% activity. if the urea were removed after oxidation occurred, the protein had less than 5% activity. why would the protein not refold correctly if the urea were removed after the reducing agent was removed? (in other words, what would happen if the urea were removed after oxidation? ) choose the best answer.

(a) urea would participate in weak bonding interactions with rnase, preventing oxidation of cys.
(b) the protein would not fully unfold (denature).
(c) disulfide bonds are not positioned correctly unless weak bonding interactions are present.
(d) contaminants in the rnase preparation would form covalent bonds with the protein, preventing reactivation.

The correct answer to the question: What would happen if the urea were removed after oxidation, would be, C: Disulfide bonds are not positioned correctly unless weak bonding interactions are present.

Explanation:

Christian Anfinsen´s and colleagues´s research on proteins, their structure, their function, and what affects them, yielded information that has impacted the way that proteins are studied today. This research was not only able to find the structure of proteins, but also how this structure was formed, and what would happen if it was affected by different factors, meaning, if the protein would remain functional or not. In his experiment with urea, Anfinsen and his colleagues found that what mattered in protein structure was the fine balance in the elements, called residue, inside the structure, and not those on the outside. They also found that when urea was removed from the protein after oxidation had happened, then the cysteine residue would not be placed correctly inside the structure, thus affecting it and reducing its capacity to perform.

1. a host loses nutrients to a parasite

2. a parasite only benefits when the host is alive (cause if the host dies the parasite dies with it )

3. producers to consumers

4. the tapeworm is a parasite

5. they convert energy from the sun (photosynthesis)

6. sunflower-robin (i think im 80% sure)

7. producer

8. consumer

9. prey

10. fresh water snails ( cause the green algea is the producer and the snails are the primary consumers and the small fish consumer so is the big fish)

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what do the different brain waves do?

explanation:

brainwaves are produced by synchronised electrical pulses from masses of neurons communicating with each other. brainwaves are detected using sensors placed on the scalp. brainwave speed is measured in hertz (cycles per second) and they are divided into bands delineating slow, moderate, and fast waves.