Ques:Answer the following question given this paragraph: The Peritoneum The digestive organs within the abdominal cavity are held in place by the peritoneum, a broad serous membranous sac made up of squamous epithelial tissue surrounded by connective tissue. It is composed of two different regions: the parietal peritoneum, which lines the abdominal wall, and the visceral peritoneum, which envelopes the abdominal organs (Figure 23.4). The peritoneal cavity is the space bounded by the visceral and parietal peritoneal surfaces. A few milliliters of watery fluid act as a lubricant to minimize friction between the serosal surfaces of the peritoneum. Q: The digestive organs within the abdominal cavity are held in place by the peritoneum, a broad serous membranous sac made up of squamous epithelial tissue surrounded by this? Choices: - mucus - skin - bone - connective tissue A:

Ans:connective tissue
-----
Ques:Answer the following question given this paragraph: A common way to keep track of valence electrons is with Lewis electron dot structures . In an electron dot structure, each atom is represented by its chemical symbol, and each valence electron is represented by a single dot. Note that only valence electrons are shown explicitly in these diagrams. For the main group elements, the number of valence electrons for a neutral atom can be determined by looking at which group the element belongs to. In the s block, Group 1 elements have one valence electron, while Group 2 elements have two valence electrons. In the p block, the number of valence electrons is equal to the group number minus ten. Group 13 elements have three valence electrons, Group 14 elements have four, and so on. The noble gases in Group 18 have eight valence electrons, and the full outer s and p sublevels are what give these elements their special stability. Representative dot diagrams are shown in the Figure below :. Q: The group 18 gases that have 8 valence electrons are referred to as what type of gases? Choices: - novel - important - metal - noble A:

Ans:noble
-----
Ques:Answer the following question given this paragraph: Predators play an important role in an ecosystem. For example, if they did not exist, then a single species could become dominant over others. Grazers on a grassland keep grass from growing out of control. Predators can be keystone species . These are species that can have a large effect on the balance of organisms in an ecosystem. For example, if all of the wolves are removed from a population, then the population of deer or rabbits may increase. If there are too many deer, then they may decrease the amount of plants or grasses in the ecosystem. Decreased levels of producers may then have a detrimental effect on the whole ecosystem. In this example, the wolves would be a keystone species. Q: What type of species have a large effect on the balance of organisms in an ecosystem? Choices: - decomposers - producers - secondary consumers - keystone A:

Ans:keystone
-----
Ques:Answer the following question given this paragraph: 5.3 Active Transport The combined gradient that affects an ion includes its concentration gradient and its electrical gradient. A positive ion, for example, might tend to diffuse into a new area, down its concentration gradient, but if it is diffusing into an area of net positive charge, its diffusion will be hampered by its electrical gradient. When dealing with ions in aqueous solutions, a combination of the electrochemical and concentration gradients, rather than just the concentration gradient alone, must be considered. Living cells need certain substances that exist inside the cell in concentrations greater than they exist in the extracellular space. Moving substances up their electrochemical gradients requires energy from the cell. Active transport uses energy stored in ATP to fuel this transport. Active transport of small molecular-sized materials uses integral proteins in the cell membrane to move the materials: These proteins are analogous to pumps. Some pumps, which carry out primary active transport, couple directly with ATP to drive their action. In co-transport (or secondary active transport), energy from primary transport can be used to move another substance into the cell and up its concentration gradient. Q: The combined gradient that affects an ion includes its concentration gradient and its what? Choices: - radiation gradient - cell membrane - electron bond - electrical gradient A:

Ans:
electrical gradient
-----