Answer the following question given this paragraph: 31.3 Nutritional Adaptations of Plants Atmospheric nitrogen is the largest pool of available nitrogen in terrestrial ecosystems. However, plants cannot use this nitrogen because they do not have the necessary enzymes. Biological nitrogen fixation (BNF) is the conversion of atmospheric nitrogen to ammonia. The most important source of BNF is the symbiotic interaction between soil bacteria and legumes. The bacteria form nodules on the legume's roots in which nitrogen fixation takes place. Fungi form symbiotic associations (mycorrhizae) with plants, becoming integrated into the physical structure of the root. Through mycorrhization, the plant obtains minerals from the soil and the fungus obtains photosynthate from the plant root. Ectomycorrhizae form an extensive dense sheath around the root, while endomycorrhizae are embedded within the root tissue. Some plantsparasites, saprophytes, symbionts, epiphytes, and insectivoreshave evolved adaptations to obtain their organic or mineral nutrition from various sources. Q: What process refers to the conversion of atmospheric nitrogen to ammonia? Choices: - biological nutrient fixation - biological ammonia fixation - biological respiratory fixation - biological nitrogen fixation A:
biological nitrogen fixation
Answer the following question given this paragraph: Anions form when an atom gains electrons. Nonmetallic atoms typically gain enough electrons to obtain the same electron configuration as the nearest noble gas. All the elements in Group 17 have seven valence electrons, which are arranged into an outer configuration of n s 2 n p 5 . To achieve a noble gas configuration ( n s 2 n p 6 ), each of these elements needs to gain just one electron, resulting in an anion with a 1 charge. Similarly, Group 16 elements can obtain an n s 2 n p 6 valence configuration by forming ions with a 2 charge, and the Group 15 nonmetals will form ions with a 3 charge. Naming anions is slightly different than naming cations. The end of the element's name is dropped and replaced with the ide suffix. For example, when the chlorine atom (Cl) gains one electron, it becomes the chloride ion (Cl - ). This structure has the same electron configuration as the noble gas argon. Similarly, sulfur can gain two electrons to become the sulfide ion (S 2- ), which also has a noble gas configuration. Q: What forms when an atom gains electrons? Choices: - cations - bonds - crystals - anions A:
anions
Q: Answer the following question given this paragraph: The Moon has a crust, mantle, and core. Q: The moon has a crust, mantle, and a? Choices: - ice cap - magnetic field - mountain range - core A:
A: core
Question: Answer the following question given this paragraph: Our Sun is a star. This star provides light and heat and supports almost all life on Earth. The Sun is the center of the solar system. It is by far the largest part of the solar system. Added together, all of the planets make up just 0.2 percent of the solar system's mass. The Sun makes up the remaining 99.8 percent of all the mass in the solar system ( Figure below )!. Q: What is the largest body in the solar system? Choices: - earth - asteroids - planet - sun A:
Answer: sun
*Question*
Answer the following question given this paragraph: Q: "crossing over" occurs during what phase of mitosis? Choices: - Prophase ii - prophase VI - prophase iii - prophase i A:
**Answer**
prophase i
(Q).
Answer the following question given this paragraph: Cubes have six sides that are all the same size square. All of the angles in a cube are equal to 90. Rhombohedra also have six sides, but the sides are diamond-shaped. Octahedra have eight sides that are all shaped like triangles. Q: What shape are the eight sides of an octahedra? Choices: - rectangles - hexagon - square - triangles A:
(A).
triangles