Lecture 5 Flashcards
The advantageous characteristics of fever has been long debated. One explanation is that the increase in temperature increases the rates of the body’s immunological reactions. Explain why you might tend to agree or disagree with this hypothesis.
Similarly to all things, there’s a threshold where something goes from being advantageous to dangerous. Yes, an increase in the body’s temperature can increase the rate of the bodies immunological responses. However, if the temperature gets to be too high then it can start to denature proteins in the body and actually stop these immunological reactions from happening entirely and possibly lead to death.
Why are enzymes a more appropriate solution to the solving the activation energy problem than
increasing temperature?
Enzymes function to decrease activation energy through stabilizing the transition state in a reaction. Increasing temperature brings the reaction to completion and allows for it to happen quicker, however it does not create stability within the reaction. It actually has the potential to create a more unstable environment if the temperature gets too high, leading to bonds breaking and the reaction not occurring.
What is the difference between an endergonic reaction and exergonic reaction?
An endogenic reaction is energy requiring/consuming and make bonds. An exergonic reaction is energy releasing and break bonds.
Define activation energy. How do enzymes function to lower the activation energy?
Activation energy is the energy required for a reaction proceed at biologically appropriate rates. Enzymes function to lower activation energy by stabilizing the transition state in a reaction and decreasing the amount energy needed to reach the transition state.
With respect to the body’s chemical reactions, why is it important to maintain the body’s temperature within relatively close range? (hint think of the effect on reactions – how will this influence cell function?
Describe how the lock and key hypothesis explains enzyme function.
Enzyme (lock) has a specific geometric shape. Substrate (key) fits perfectly into shape. Only correct substrate can fit.
Why are enzymes described as the body’s biological “ON Switches” for chemical reactions?
They act as catalysts to speed up and regulate biological chemical reactions. They lower activation energy, are highly specific to a particular reaction or substrate, can be turned “on” or “off” through inhibitors, activators, or environmental factors, and can be reused repeatedly because they’re not consumed in reactions.
Niacin, Riboflavin, Ca2+, Vit A, etc. are examples of Cofactors and coenzymes. If one were
deficient in one or more of these cofactors and/or coenzymes many enzymatic reactions may not
occur at an optimal rate. Explain why? How do Co-factors assist enzyme catalyzed reactions?
This is because these cofactors and coenzymes
Temperature and pH are important internal parameters to maintain constant for optimal
enzymatic activity. With your understanding of proteins and enzymes why is this the case. Include
why the exact shape of the enzyme is so critical to its function.
Looking closely at the structure of ATP and using your knowledge of atoms and
molecules, explain why the breaking of a single phosphate bond releases SOOO
much energy.
Describe the difference between oxidation and reduction in terms of electron
transfer and hydrogen ion transfer. Why do they refer to Oxidation reduction
reactions as coupled?
Why do you think hydrogen is a good electron carrier? (hint: think of how many
electrons it contains)
Although not all oxidation / reduction reactions involve oxygen, why are the
reactions still referred to as oxidation?
