Study Question 9

The zooplankton can be characterized by which of the following terms?

primary consumers herbivores heterotrophs

Explain how you obtained your answer to question # 16 above.

1% of sunlight is trapped by the producers; therefore the producers (phytoplankton) contain 80,000 kcal (1/4 pt.) • Ideally, 10% of energy available at each trophic level becomes incorporated into the next higher level. • The energy contained in the (producers) is 80,000 kcal. Using the 10% rule, the primary consumers (zooplankton) would contain 8000 kcal (10% of 80,000) and the secondary consumers (herring) would contain 800 kcal (10% of 8000) and the tertiary consumer (mackerel) would contain 80kcal (10% of 800). and the quaternary consumer (tuna) would contain 8 kcal) (10% of 80

The total amount of activation energy required for the reaction to go to completion with an enzyme present is _____Kcal

10

Which numbered label represents the transport protein?

2

Which numbered label represents ATP?

3

The total amount of activation energy required for the reaction to go to completion without an enzyme present is _____Kcal

30

What is the total amount of energy (in Kcal) released by this reaction when in the absence of an enzyme?

30

What is the total amount of energy (in Kcal) released by this reaction when in the presence of an enzyme?

30

The optimum temperature for carnosinase activity is _____ oC. Be as precise as possible.

38 degrees Celsius

Which numbered label represents a phosphate molecule?

4

Ideally, how much energy (in kcal) would be available for use by the herring?

800kcal

Describe what occurs during the process of phosphorylation of molecules by ATP.

A phosphate functional group is transferred from ATP to another molecule, (thus energizing that molecule.)

Check all of the true statements concerning ATP.

ATP is a nucleotide composed of the 5 carbon sugar ribose, the nitrogen base adenine, and 3 phosphate functional groups. The entire amount of ATP in an organism is recycled once per minute. Cells produce ATP as a result of the biochemical reactions of cellular respiration. ATP transfers energy to other molecules during the process of phosphorylation. These energized molecules can then do work for the cell.

In this example, what happens to the transport protein as a result of it becoming phosphorylated and how does this change result in the movement of the solute?

As a result of being phosphorylated, the transport protein changes its shape. The change in shape allows the solute to be transported across the membrane.

Which diagram shows the process of phosphorylation of the transport protein?

B

Which of the following are true statements concerning enzymes?

Enzymes generally catalyze only very specific biochemical reactions. If the active site of an enzyme is altered, the enzyme is unable to catalyze the biochemical reaction Most enzymes are proteins composed of amino acids. The cells of both eukaryotes and prokaryotes all contain enzymes

How would you best describe this biochemical reaction?

Exergonic, net energy yielding reaction

Explain the significance of arrow #6.

The enzyme is re-used to catalyze the reaction again.

Question #20 above refers to the complex between molecules 1 and 4. What is happening at this stage of the enzyme reaction which facilitates the reaction to go to completion more rapidly than if no enzyme was present?

When the enzyme binds to the substrate, the chemical bonds of the substrate are stressed. • As a result, less energy is needed break the bonds of the substrate to start the reaction than if no enzyme was present.

The region of molecule 4 labeled by bracket A is the _______.

active site

Check all of the true statements concerning the biochemical reaction represented by arrow #2.

endergonic reaction dehydration synthesis reaction phosphorylation reaction

The second graphic from the left shows molecule 1 in close association with molecule 4. What is the name of this complex (i.e. #1 and #4 together)?

enzyme substrate complex

Arrow A represents energy input from __________ reactions such as cellular respiration and Arrow B represents energy output required by _______ reactions utilized by cells to carry out their life processes.

exergonic; endergonic

Mackerel are a species of marine fish which can best be characterized by which of the following terms?

heterotrophs tertiary consumers carnivores

The enzyme carnosinase would be synthesized on what structures within the cell cytoplasm?

ribosomes

The phytoplankton can be characterized by which of the following terms?

primary producers photosynthetic autotrophs

Based on your knowledge of enzymes, give one reason why there is a steady increase in carnosinase activity between points A and B as the temperature increases.

higher temperatures increase the rate at which enzyme collide to form the enzyme-substrate complex resulting in an increase in the rate of the enzyme catalyzed reaction • once the enzyme substrate complex is formed, the atoms in the bonds holding the substrate together begin to move faster (become agitated) resulting in the weakening of these bonds making it easier for the substrate bonds to break and a higher reaction rate

Check all of the true statements concerning the biochemical reaction represented by arrow #1.

hydrolysis and exergonic reaction

Arrow 5 represents the addition of ________ to the reaction

water

Based on solute concentration, why is this an example of active transport?

Solutes are moving from a region of low concentration (outside the cell) to a region of high concentration (inside the cell).

Explain what is happening to the secondary and tertiary folding of the polypeptide chain making up the carnosinase enzyme. Explain how this alteration in the 3-D structure of carsinoase affects the structure of the active site of carsinoase and why this results in a decrease in carsinoase activity.

denaturation of an enzyme results in the alteration of its secondary and/or tertiary 3-D structure; as a result the shape of the active site is changed. • as a result the enzyme is unable to bind to the substrate, causing the reaction rate to slow and finally the reaction to cease. The primary structure of the protein composing the enzyme is unaffected by the high temperature.