BIO test 2
You are looking at a sample under a light microscope and observe a new type of cell. You come to the conclusion that it is a bacterium and not a eukaryotic cell. What would you observe to come to this conclusion?
the cell does not have a nucleus
Macrophages ingest and digest many pathogens. Which organelle plays a major role in the activity of macrophages?
lysosome
The hydrolysis of one ATP molecule releases 7.3kcal/mol of energy (ΔG=−7.3kcal/mol of energy ). If it takes 2.1kcal/mol of energy to move one Na+ across the membrane (ΔG=+2.1kcal/mol of energy ), what is the maximum number of sodium ions that could be moved by the hydrolysis of one ATP molecule?
3
Why is it beneficial for cells to use ATP rather than directly using the energy stored in the bonds of carbohydrates to power cellular reactions? What are the greatest drawbacks to harnessing energy from the bonds of several different compounds?
ATP is readily available in the form of a single unit that provides a consistent, appropriate amount of energy. The cell would need to tailor each reaction to each energy source if it harvested energy from different compounds.
Energy transfers take place constantly in every day activities. Think of two scenarios: cooking on a stove and driving. Explain how the second law of thermodynamics applies to these scenarios.
Heat is lost into the room while cooking and into the metal of the engine during gasoline combustion.
What role does NAD+ play in redox reactions?
NAD+, an oxidizing agent, can accept electrons and protons from organic molecules and get reduced to NADH NADH .
What happens when potential energy is turned into kinetic energy?
Potential energy will be expressed in the form of heat, movement or work.
Which statement best explains how electrons are transferred and the role of each species. Remember that R represents a hydrocarbon molecule and RH represents the same molecule with a particular hydrogen identified. RH+NAD+→NADH+R
RH acts as a reducing agent and donates its electrons to the oxidizing agent NAD+ NAD+, forming NADH and R
How do the nucleus and the endomembrane system work together for protein synthesis?
The endomembrane system processes and ships proteins specified by the nucleus. In the nucleus, DNA is used to make RNA which exits the nucleus and enters the cytoplasm of the cell. The ribosomes on the rough ER use the RNA to create the different types of protein needed by the body.
What happens to the proteins that are synthesized on free ribosomes in the cytoplasm? Do they go through the Golgi apparatus?
The proteins do not go through the Golgi apparatus and remain free in the cytosol.
Describe the position of the transition state on a vertical energy scale, from low to high, relative to the position of the reactants and products, for both endergonic and exergonic reactions.
The transition state of the reaction exists at a higher energy level than the reactants. Activation energy is always positive regardless of whether the reaction is exergonic or endergonic.
restro virus
changes genetic makeup
Which organelles would be present in high numbers in the leg muscles of a marathon runner?
mitochondria
How does the change in Gibbs free energy (ΔG) differ between the catalyzed versus uncatalyzed reaction?
ΔG is the same for the catalyzed and uncatalyzed reactions.
