Answer the following question given this paragraph: The replacing of the electron enables chlorophyll to respond to another photon. The oxygen molecules produced as byproducts find their way to the surrounding environment. The hydrogen ions play critical roles in the remainder of the light-dependent reactions. Keep in mind that the purpose of the light-dependent reactions is to convert solar energy into chemical carriers that will be used in the Calvin cycle. In eukaryotes and some prokaryotes, two photosystems exist. The first is called photosystem II, which was named for the order of its discovery rather than for the order of the function. After the photon hits, photosystem II transfers the free electron to the first in a series of proteins inside the thylakoid membrane called the electron transport chain. As the electron passes along these proteins, energy from the electron fuels membrane pumps that actively move hydrogen ions against their concentration gradient from the stroma into the thylakoid space. This is quite analogous to the process that occurs in the mitochondrion in which an electron transport chain pumps hydrogen ions from the mitochondrial stroma across the inner membrane and into the intermembrane space, creating an electrochemical gradient. After the energy is used, the electron is accepted by a pigment molecule in the next photosystem, which is called photosystem I (Figure 5.13). Q: What type of ions play critical roles in light-dependent reactions? Choices: - calcium - silicon - helium - hydrogen A:
hydrogen

Answer the following question given this paragraph: Polymers are long molecules composed of chains of units called monomers. Q: What long molecules are composed of chains of units called monomers? Choices: - complexes - microbes - drummers - polymers A:
polymers

Answer the following question given this paragraph: The cut on your hand may become red, warm, and swollen. These are signs of an inflammatory response. This is the first reaction of the body to tissue damage or infection. As explained in Figure below , the response is triggered by chemicals called cytokines and histamines , which are released when tissue is injured or infected. The chemicals communicate with other cells and coordinate the inflammatory response. You can see an animation of the inflammatory response at this link: http://www. sumanasinc. com/webcontent/animations/content/inflammatory. html . Q: The first reaction of the body to tissue damage or infection is called the what response? Choices: - defensive - harmful - retaliatory - inflammatory A:
inflammatory

Answer the following question given this paragraph: A: Breathing consists of inhaling and exhaling, and its purpose is to move gases into and out of the body. Oxygen needed for cellular respiration is brought into the body with each inhalation. Carbon dioxide and water vapor produced by cellular respiration are released from the body with each exhalation. Q: How is carbon dioxide and water vapor that is produced by cellular respiration released? Choices: - peroxidation - fermentation - evaporation - exhalation A:
exhalation