Answer the following question given this paragraph: Q: Exchange occurs directly with the external environment in what type of organisms? Choices: - hematopoietic organisms - cell clusters - multicellular organisms - unicellular organisms A:
unicellular organisms
Answer the following question given this paragraph: Second, plant cells have a cell wall , while animal cells do not ( Figure below ). The cell wall surrounds the plasma membrane but does not keep substances from entering or leaving the cell. A cell wall gives the plant cell strength and protection. Q: What gives the plant cell strength and protection? Choices: - the protons - the cell nucleus - the genes - a cell wall A:
a cell wall
Q: Answer the following question given this paragraph: Plants are multicellular eukaryotes. They have organelles called chloroplasts and cell walls made of cellulose. Plants also have specialized reproductive organs. Almost all plants make food by photosynthesis. Life as we know it would not be possible without plants. Q: How do most plants create food? Choices: - electrolysis - atherosclerosis - glycolysis - photosynthesis A:
A: photosynthesis
Question: Answer the following question given this paragraph: At 1600 C, quartz melts to yield a viscous liquid. When the liquid cools, it does not crystallize readily but usually supercools and forms a glass, also called silica. The SiO4 tetrahedra in glassy silica have a random arrangement characteristic of supercooled liquids, and the glass has some very useful properties. Silica is highly transparent to both visible and ultraviolet light. For this reason, it is important in the manufacture of lamps that give radiation rich in ultraviolet light and in certain optical instruments that operate with ultraviolet light. The coefficient of expansion of silica glass is very low; therefore, rapid temperature changes do not cause it to fracture. CorningWare and other ceramic cookware contain amorphous silica. Silicates are salts containing anions composed of silicon and oxygen. In nearly all silicates, sp3-hybridized silicon atoms occur at the centers of tetrahedra with oxygen at the corners. There is a variation in the silicon-to-oxygen ratio that occurs because silicon-oxygen tetrahedra may exist as discrete, independent units or may share oxygen atoms at corners in a variety of ways. In addition, the presence of a variety of cations gives rise to the large number of silicate minerals. Many ceramics are composed of silicates. By including small amounts of other compounds, it is possible to modify the physical properties of the silicate materials to produce ceramics with useful characteristics. Q: Many ceramics are composed of what, which are salts containing anions composed of silicon and oxygen? Choices: - vinylates - crystals - soils - silicates A:
Answer: silicates
*Question*
Answer the following question given this paragraph: Metallic Solids Metals are characterized by their ability to reflect light, called luster, their high electrical and thermal conductivity, their high heat capacity, and their malleability and ductility. Every lattice point in a pure metallic element is occupied by an atom of the same metal. The packing efficiency in metallic crystals tends to be high, so the resulting metallic solids are dense, with each atom having as many as 12 nearest neighbors. Bonding in metallic solids is quite different from the bonding in the other kinds of solids we have discussed. Because all the atoms are the same, there can be no ionic bonding, yet metals always contain too few electrons or valence orbitals to form covalent bonds with each of their neighbors. Instead, the valence electrons are delocalized throughout the crystal, providing a strong cohesive force that holds the metal atoms together. Q: What category of elements are chacterized by their ability to reflect light, called luster, their high electrical and thermal conductivity, their high heat capacity, and their malleability and ductility? Choices: - halogens - nonmetals - noble gases - metals A:
**Answer**
metals
Answer the following question given this paragraph: Ether molecules have an oxygen atom and can engage in hydrogen bonding with water molecules. An ether molecule has about the same solubility in water as the alcohol that is isomeric with it. Q: Ether molecules have an oxygen atom and can engage in hydrogen bonding with which other molecules? Choices: - carbon dioxides - proteins - lipids - water A:
water