*The key function of each of the two photosystems is to absorb light and convert the energy of the absorbed light into redox energy, which drives electron transport.
In PS II (the first photosystem in the sequence), P680 is oxidized (which in turn oxidizes water), and the PS II primary electron acceptor is reduced (which in turn reduces the electron transport chain between the photosystems).
In PS I, the PS I primary electron acceptor is reduced (which in turn reduces other compounds that ultimately reduce NADP+ to NADPH), and P700 is oxidized (which in turn oxidizes the electron transport chain between the photosystems).
Answer:
Abstract
Respiratory homeostasis is concerned with the regulation of a blood gas composition that is compatible with maintaining cellular homeostasis. Provided that the lung-capillary exchange barrier does not prevent the exchange of gases, then blood leaving the lung will have oxygen and carbon dioxide partial pressures that are similar to the average values found in the alveoli. Alveolar ventilation establishes these values. If blood gas composition, especially of carbon dioxide, moves outside the homeostatic range, the change is detected by chemoreceptors and respiratory responses are promoted which change alveolar ventilation, alter alveolar gas composition and so reverse the change. Ventilation therapies provide the means of artificially restoring alveolar gas composition. In general terms, they do this by raising the partial pressure of oxygen within the alveoli either by using oxygen-enriched gas mixtures, or by improving the ventilation of alveoli using positive pressure.
Explanation:
3# Interphase is divided into three phases: G1, S, and G2. The subsequent mitotic (M) phase consists of two processes: mitosis, the process of nuclear division, and cytokinesis, division of the cell's cytoplasm. Each mitotic phase results in the formation of two cells that are genetically identical to the parent.
Sorry I can't remember the rest of the questions.
For this item, I would go with letter "D. physical destruction of marine habitats". Many of the modern ways of fishing poses an irreversible destruction to marine habitats. These practices include trawling, lining methods, purse seining, etc.
