Answer the following question given this paragraph: Vertebrate Digestive Systems Vertebrates have evolved more complex digestive systems to adapt to their dietary needs. Some animals have a single stomach, while others have multi-chambered stomachs. Birds have developed a digestive system adapted to eating unmasticated food. Monogastric: Single-chambered Stomach As the word monogastric suggests, this type of digestive system consists of one ("mono") stomach chamber ("gastric"). Humans and many animals have a monogastric digestive system as illustrated in Figure 34.6ab. The process of digestion begins with the mouth and the intake of food. The teeth play an important role in masticating (chewing) or physically breaking down food into smaller particles. The enzymes present in saliva also begin to chemically break down food. The esophagus is a long tube that connects the mouth to the stomach. Using peristalsis, or wave-like smooth muscle contractions, the muscles of the esophagus push the food towards the stomach. In order to speed up the actions of enzymes in the stomach, the stomach is an extremely acidic environment, with a pH between 1.5 and 2.5. The gastric juices, which include enzymes in the stomach, act on the food particles and continue the process of digestion. Further breakdown of food takes place in the small intestine where enzymes produced by the liver, the small intestine, and the pancreas continue the process of digestion. The nutrients are absorbed into the blood stream across the epithelial cells lining the walls of the small intestines. The waste material travels on to the large intestine where water is absorbed and the drier waste material is compacted into feces; it is stored until it is excreted through the rectum. Q: Vertebrates have evolved more complex digestive systems, with some species having multi-chambered types of what organ? Choices: - respiratory - skin - heart - stomach A:
stomach
Answer the following question given this paragraph: Solutes change the physical properties of solvents. They lower the freezing point and raise the boiling point of solvents. Q: What change the physical properties of solvents? Choices: - molecules - cells - chemical reactions - solutes A:
solutes
Q: Answer the following question given this paragraph: Another sign of a species' state of health is the density of its populations. Population density is the average number of individuals in a population for a given area. Density is a measure of how crowded or spread out the individuals in a population are on average. For example, a population of 100 deer that live in an area of 10 square kilometers has a population density of 10 deer per square kilometer. Q: What is the term for the average number of individuals in a population for a given area? Choices: - result density - population structure - Area Density - population density A:
A: population density
Question: Answer the following question given this paragraph: Flowers are the reproductive organs of plants. Each pea plant flower has both male and female parts. The anther is part of the stamen, the male structure that produces male gametes (pollen). The stigma is part of the pistil, the female structure that produces female gametes and guides the pollen grains to them. The stigma receives the pollen grains and passes them to the ovary, which contains female gametes. Q: What female flower structure, which is part of the pistil, receives the pollen grains and passes them to the ovary? Choices: - sepal - style - ovary - stigma A:
Answer: stigma
*Question*
Answer the following question given this paragraph: Conceptual Questions 19.1 Electric Potential Energy: Potential Difference 1. Voltage is the common word for potential difference. Which term is more descriptive, voltage or potential difference? 2. If the voltage between two points is zero, can a test charge be moved between them with zero net work being done? Can this necessarily be done without exerting a force? Explain. What is the relationship between voltage and energy? More precisely, what is the relationship between potential difference and electric potential energy? 4. Voltages are always measured between two points. Why? 5. How are units of volts and electron volts related? How do they differ?. Q: What is the common word for potential difference in a circuit? Choices: - watt - velocity - frequency - voltage A:
**Answer**
voltage
Q: Answer the following question given this paragraph: You can see how Mendeleev organized the elements in Figure below . From left to right across each row, elements are arranged by increasing atomic mass. Mendeleev discovered that if he placed eight elements in each row and then continued on to the next row, the columns of the table would contain elements with similar properties. He called the columns groups . They are sometimes called families, because elements within a group are similar but not identical to one another, like people in a family. Q: In the periodic table, elements are arranged from left to right according to what property? Choices: - metallic mass - real mass - major mass - atomic mass A:
A: atomic mass