Lesson 8

Which of the following is/are required for the complete oxidation of glucose? -Glycolysis -Krebs cycle -Pyruvate oxidation -All of these reactions

-All of these reactions All three of these processes are required for the complete oxidation of glucose. These processes are connected - the products of one stage feed into the next stage as reactants.

NAD+

-oxidized form of NAD (electron carrier involved in glycolysis, nicotinamide adenine dinucleotide) -when electrons are removed

Hydrolysis

-process of breaking complex macromolecules apart -water is split (lysed) and the resulting hydrogen atom (H+) and a hydroxyl group (OH-) are added to larger molecule

Hydrolysis of ATP

-produces ADP with an inorganic phosphate ion and the release of free energy

NADH

-reduced form of molecule NAD -after it has accepted two electrons and a proton (the equivalent of hydrogen atom with an extra electron) -when electrons are gained -usually H in compound= reduced

oxidation reaction

-strips an electron from an atom in a compound -decrease in potential energy in this compound

Classify the following organisms as autotrophs or heterotrophs: 1.Plants 2.Humans 3.Green Algae 4.Fungi

1.Autotrophs 2.Heterotrophs 3.Autotrophs 4.Heterotrophs

after pyruvate oxidation how many carbons from the original glucose are left to enter the krebs cycle? -2 -3 -4 -5

4

Use the diagram of the mitochondrion shown below to answer this matching question. (page 7) A: B: C: D:

A: Outer membrane B: inner membrane C: matrix D: cytosol

Refer to the following diagram of cellular respiration. Note that the letter above the arrows indicates the products from the previous stage that serve as reactants for the next stage. glycolysis --- (A)---> pyruvate oxidation --- (B)--> Kreb Cycle ---(C)--->electron Transport chain A: B: C:

A: Pyruvate B: Acetyl-CoA C: NADH and FADH2 -The products of one series of reactions serve as the reactants of the next series of reactions. This allows cells to harvest energy with maximum efficiency.

during glycolysis which step happens first -nadh is produced -ATP is hydrolyzed to ADP -a 6 carbon molecule is broken into 2 3carbon molecules -ATP is produced via substrate-level phosphorylation

ATP is hydrolyzed into ADP

Only heterotrophs use the process of glycolysis to generate energy. T/F

F- ALL organisms can use glycolysis to generate energy

For each glucose molecule catabolized, how many TOTAL ATP molecules are produced by substrate-level phosphorylation during this stage?

For each glucose molecule catabolized, the total number of ATP molecules that are produced by substrate level phosphorylation is 2.

In 1-2 sentences, define substrate-level phosphorylation in your own words

Substrate level phosphorylation is the process of obtaining energy on the go. The enzyme PEP is able to phosphorylate ADP into ATP. There is a phosphate group added in the intermediate step causing the adenosine diphosphate to become adenosine triphosphate.

Substrate-level phosphorylation occurs during glycolysis and one of the other stages of cellular respiration of glucose described in Lesson 8. Which stage is this?

Substrate level phosphorylation occurs in glycolysis and the krebs cycle.

Autotrophs use photosynthesis to generate organic molecules and ATP as energy sources. T/F

T

during glycolysis the glucose based carbon molecule G3P is being ____ and the electron carrier is being ___ -oxidized, reduced -reduced, oxidized -oxidized, oxidized -reduced, reduced

oxidized, reduced

The intermediate electron carrier nicotinamide adenosine dinucleotide (NAD+) plays an important role in glycolysis. Consider the redox reaction of NAD+ as the reaction below. H2 + NAD+ --> NADH + H+ NAD+ is _____ to NADH as a result of the _____ of electrons.

reduced, gain

the primary role of the krebs cycle can be best described as -the primary generator of ATP -the process that oxidizes a 3 carbon molecule into a 2 carbon molecule -the primary contributor of electrons to electron carriers

the primary contributer of electrons to electron carriers

Which of the following is true about the process of cellular respiration? Select ALL answer choices that apply. -No input of energy is necessary for the process to occur. -An input of energy is required for the process to begin. -ATP is the only source of energy that is harvested from respiration. -Energy is harvested in the forms of ATP and electron carriers.

-An input of energy is required for the process to begin. -Energy is harvested in the forms of ATP and electron carriers (In glycolysis alone, 2 ATP are required to 'prime' the reaction and 2 ATP molecules are harvested.)

reduction reaction

-addition if this electron to another compound -increases potential energy in this compound

The release of one or two phosphate groups from ATP is called ___________, and _____________ energy

-dephosphorylation -releases

redox reaction

-oxidation and reduction occur together, these pairs of reactions are called oxidation reduction reactions, or also ___________.

Identify where each of the following stages of respiration takes place. (page 7) Pyruvate Oxidation: Krebs Cycle: Glycolysis:

Pyruvate Oxidation: C Krebs Cycle: C Glycolysis: D

The Krebs cycle is largely considered to be the central pathway of the cell, but only produces a single ATP molecule per turn. Briefly explain how the Krebs cycle can be the central metabolic pathway of the cell when it produces so little ATP.

The krebs cycle is the central part of the metabolic pathway because it is able to obtain the most electron carriers. Its role is to steal as much energy out of the carbon molecules (increased electrons). This will set up the electron transport chain for the most success and most ATP production. This process also adds NADH and FADH2.

Is cellular respiration aerobic or anaerobic?

aerobic

Is cellular respiration endergonic or exergonic?

exergonic

The chemical equation for cellular respiration is shown below. C6H12O6 + 6O2 ---> 6CO2 + 6H20 ΔG= -6686 kcal/mol glucose Energy is released as the bonds in __________ are systematically broken down. Since energy is released, this reaction can be classified as ["endergonic", "exergonic"]. The energy obtained from respiration is harvested ["all at once", "in small steps"] for maximum efficiency.

glucose exergonic in small steps