Biology Questions Quiz Test: MCQ!

Food is the correct answer because it provides the necessary calories for humans to obtain energy. While minerals and water are important for overall health, they do not directly provide calories. Sunlight is a source of energy for plants through photosynthesis, but humans cannot directly obtain energy from sunlight. Therefore, food is the correct answer as it is the primary source of calories and energy for humans.

The correct answer is 200,000. This is because the label on the breakfast cereal box states that one serving contains "200 Calories" per serving. Therefore, there are actually 200,000 calories in one serving.

During glycolysis, a metabolic pathway that occurs in the cytoplasm of cells, glucose is broken down into two molecules of pyruvate. This process generates a small amount of ATP through substrate-level phosphorylation. For each molecule of glucose, there is a net gain of 2 ATPs produced. Therefore, the correct answer is 2.

The statement that cellular respiration is a single chemical reaction with just one step is false. Cellular respiration is a complex process that occurs in multiple steps, involving various metabolic pathways. It includes glycolysis, the Krebs cycle, and oxidative phosphorylation, which all contribute to the production of ATP, water, and carbon dioxide. Therefore, cellular respiration is not a single step reaction but a series of interconnected reactions.

The drug's ability to create holes in both mitochondrial membranes suggests that it will disrupt the process of oxidative phosphorylation. This process is crucial for the production of ATP, the main energy source for cells. If oxidative phosphorylation is inhibited, the cells will not be able to produce sufficient energy, leading to harmful effects on human cells.

The end products of the citric acid cycle, also known as the Krebs cycle, include FADH2, CO2, and ATP. Pyruvate acid is not an end product of this cycle, but rather a starting molecule that enters the cycle through a series of reactions.

The end products of glycolysis include NADH. Glycolysis is the first step in cellular respiration, where glucose is broken down into pyruvate. During this process, NAD+ is reduced to NADH, which carries high-energy electrons to the electron transport chain for ATP production. NADH is an important molecule in energy metabolism as it plays a crucial role in the production of ATP through oxidative phosphorylation.

In the electron transport chain, electrons are passed along a series of protein complexes, ultimately leading to the formation of ATP. Oxygen acts as the final electron acceptor in this process, combining with hydrogen ions to form water. This is known as oxidative phosphorylation, where the energy from the electrons is used to generate ATP. Therefore, the correct answer is an oxygen atom.

Yeasts have the ability to produce ATP through both fermentation and oxidative phosphorylation. This means that they can generate energy in the absence of oxygen through fermentation, as well as in the presence of oxygen through oxidative phosphorylation. As facultative anaerobes, yeasts can switch between these two metabolic pathways depending on the availability of oxygen.

Insects exposed to rotenone will die because it inhibits the production of ATP. ATP is the main energy source for cellular processes, and without adequate ATP production, the insects' cells will not have enough energy to carry out essential functions. This will ultimately lead to their death.