Cell Biology Exam Review

Flashcards about cell biology, mitosis, meiosis, photosynthesis, cellular respiration and related concepts, intended for exam review.

What are the parts of the mitochondrion that should be labeled?

Inner and outer membranes, intermembrane space, and the matrix.

Where do glycolysis, pyruvate oxidation, the citric acid cycle, and fermentation occur in eukaryotic cells?

Glycolysis occurs in the cytoplasm; pyruvate oxidation, the citric acid cycle, and fermentation occur in the mitochondria.

Where is the respiratory chain (electron transport chain) located and where does ATP synthase operate?

The respiratory chain is located in the inner mitochondrial membrane; oxidative phosphorylation by ATP synthase happens in the inner mitochondrial membrane.

What is the functional importance of the respiratory electron transport chain to cellular respiration and ATP synthesis?

The respiratory electron transport chain is functionally important because it creates a proton gradient that drives ATP synthesis by ATP synthase.

Why do the citric acid cycle and the mitochondrial electron transport chain shut down in the absence of oxygen?

The citric acid cycle and the mitochondrial electron transport chain shut down in the absence of oxygen, because oxygen is required as the final electron acceptor in the electron transport chain and the cycle needs the products of the electron transport chain to function.

Why is NAD+ the most important product of fermentation?

NAD+ is required for glycolysis to continue. Fermentation regenerates NAD+ from NADH, allowing glycolysis to continue in the absence of oxygen.

What are the two major functional domains of ATP synthase?

The two major functional domains of ATP synthase are the F0 domain (embedded in the membrane) and the F1 domain (protruding into the matrix).

How do reduction and oxidation of the complexes in electron transport chains and the transport of hydrogen ions across a membrane provide the energy needed to make ATP in chloroplasts and in mitochondria?

Reduction and oxidation of the complexes in electron transport chains create a hydrogen ion gradient across a membrane, which then drives ATP synthase to make ATP.

Explain the importance of a hydrogen ion gradient to ATP production in mitochondria.

The hydrogen ion gradient provides the potential energy that drives ATP synthesis by ATP synthase.

Draw a chloroplast and label its parts; identify the locations of the light-dependent reactions, the Calvin cycle, chlorophyll molecules, the electron transport chain, and ATP synthase molecules.

Inner, outer, and thylakoid membranes; the thylakoid lumen and the stroma; the light-dependent reactions occur in the thylakoid membrane; the Calvin cycle occurs in the stroma; chlorophyll molecules are located in the thylakoid membrane; the electron transport chain is located in the thylakoid membrane, and ATP synthase molecules are located in the thylakoid membrane.

List the inputs and outputs of the light-dependent reactions and of the Calvin cycle.

The inputs of the light-dependent reactions are light, water, ADP, and NADP+; the outputs are ATP, NADPH, and oxygen. The inputs of the Calvin cycle are carbon dioxide, ATP, and NADPH; the outputs are G3P, ADP, and NADP+.

What pathway in photosynthesis transforms and captures light energy as chemical energy?

The light-dependent reactions.

What pathway in photosynthesis stores chemical energy (high-energy electrons) in a carbohydrate molecule?

The Calvin cycle.

What happens in each of the three stages of the Calvin cycle, and identify the specific stage(s) in which CO2, ATP, and NADPH are used.

Carbon fixation, reduction, and regeneration of the CO2 acceptor (RuBP). CO2 is used in carbon fixation; ATP and NADPH are used in the reduction stage.

What are the two potential fates of the three-carbon product (G3P) of the Calvin cycle?

G3P can be exported to the cytoplasm and used to make sucrose, or it can be used to synthesize glucose, which can be used to make other organic molecules.

List the two major polysaccharides synthesized from the three-carbon sugars produced in photosynthesis and describe their importance to the plant.

Starch and cellulose. Starch is used for energy storage, and cellulose is used for structural support.

List the characteristics of living organisms.

Contain genetic program, can grow and reproduce, harvest, transform, and use energy and chemical building blocks, respond to their surroundings, regulate their internal environment, and consist of one or more cells.

Why do cells divide?

During embryonic development, for replacement and repair, and to create new organisms.

What are the outcomes of mitotic and meiotic cell division?

Mitotic cell division results in two genetically identical daughter cells; meiotic cell division results in four genetically different daughter cells.

Describe what happens during the cycle in G1, S, G2 (and G0) of interphase and during mitosis and cytokinesis of M phase.

G1 phase involves preparation for DNA synthesis; S phase involves DNA synthesis; G2 phase involves preparation for mitosis and cytokinesis; mitosis involves division of the nucleus; cytokinesis involves division of the cytoplasm.

Why is mitosis not a synonym for M phase?

M phase includes both mitosis and cytokinesis, but mitosis only refers to the division of the nucleus.

What mainly happens during the G2 phase?

A cell prepares to divide.

What happens during interphase?

The period between M phases.

What happens during the G0 phase?

Cells in this particular phase do not divide.