Honors Biology: Unit 6 - Cellular Respiration Check & Challenges

Aerobic respiration

________ produces 36 ATP molecules, while fermentation produces only 2 ATP molecules.

Proteins

________ are brought into the Krebs cycle by having digestive enzymes break ________ down into amino acids first, other enzymes remove the amino groups and ammonia is converted into safer nitrogen compounds, which may be recycled or excreted.

Plants

________ use the heat energy to get pollinated through various means, including attracting certain insects with certain odors and melting through snow to survive.

Oxygen

________ is involved in cell respiration (the last step, as its the final electron acceptor that helps electrons move down the electron transport chain) by the fact that it is needed to oxidize glucose.

Fats

________ are brought in by first breaking down into glycerol and fatty acid.

Animals

________ use the heat energy to assist with hibernation, which is active at the end; ________ must quickly raise their body temperature to normal levels in order to fully awaken.

Carbon skeletons

________ are involved in biosynthesis because they are products of cell respiration, which are used to provide energy to perform the cellular work.

Krebs cycle

Who is so important in metabolism because it is involved in not only the breakdown of carbohydrates, but also fats and proteins? Answer with a single words or term.

Glucose

________ is not a direct source of cellular energy because the body utilizes it much less efficiently than ATP.

products of each stage of respiration

The ________ are as follows: in glycolysis, ATP, pyruvate, NADH, and carbon skeletons are produced (2 molecules each); in the Krebs cycle, 2 CO2 molecules, 3 NADH molecules, 1 FADH2 molecule, and 1 ATP molecule are produced.

cycle

The Krebs cycle is so important in metabolism because it is involved in not only the breakdown of carbohydrates, but also fats and proteins. This ________ breaks down acetate from fatty acids and sugars.

membrane

The outer ________ regulates the movement of molecules flowing in and out of the mitochondria.

advantage of the stepwise nature of the reactions of cell respiration

The ________ is that less energy is wasted; the body can use glucose much more efficiently.

presence of oxygen

The ________ determines the fate of pyruvate in cells; with enough oxygen, the Krebs cycle can work, but with insufficient oxygen, animal and some bacteria cells reverse the oxidation produced by the pyruvate, and the cell will be forced to convert NADH and pyruvate into NAD+ and lactate (3- carbon acid); NAD- cycles back to glycolysis, which provides small amounts of ATP until more oxygen becomes available.

Oxygen

________ is necessary for the respiration of fat because the process skips glycolysis.

aerobic respiration

Conclusively, ________ produces 18 times (18x) the number of ATP molecules compared to the less efficient fermentation.

Animals

________ use the thermal energy to stay alive, as do plants.

carbon skeletons

The ________ remaining from some amino acids can undergo reactions that form 4- or 5- carbon acids, oxaloacetate or ketoglutarate, which can finally enter the Krebs cycle.