Answer the following question given this paragraph: A mixture is a combination of two or more substances in any proportion. This is different from a compound, which consists of substances in fixed proportions. The substances in a mixture also do not combine chemically to form a new substance, as they do in a compound. Instead, they just intermingle and keep their original properties. The lemonade pictured above is a mixture because it doesn't have fixed proportions of ingredients. It could have more or less lemon juice, for example, or more or less sugar, and it would still be lemonade. Q: In what do substances combine chemically to form a new substance? Choices: - suspension - component - element - compound A:
compound
(Question)
Answer the following question given this paragraph: Accuracy and Precision of a Measurement Science is based on observation and experimentthat is, on measurements. Accuracy is how close a measurement is to the correct value for that measurement. For example, let us say that you are measuring the length of standard computer paper. The packaging in which you purchased the paper states that it is 11.0 inches long. You measure the length of the paper three times and obtain the following measurements: 11.1 in. , 11.2 in. , and 10.9 in. These measurements are quite accurate because they are very close to the correct value of 11.0 inches. In contrast, if you had obtained a measurement of 12 inches, your measurement would not be very accurate. The precision of a measurement system is refers to how close the agreement is between repeated measurements (which are repeated under the same conditions). Consider the example of the paper measurements. The precision of the measurements refers to the spread of the measured values. One way to analyze the precision of the measurements would be to determine the. Q: How close a measurement is to the correct value for that measurement is known as what? Choices: - frequency - rate - temperature - accuracy A:
(Answer)
accuracy
Ques: Answer the following question given this paragraph: Arthropods range in length from about 1 millimeter (0.04 inches) to 4 meters (about 13 feet). They have a segmented body with a hard exoskeleton. They also have jointed appendages. The body segments are the head, thorax, and abdomen (see Figure below ). In some arthropods, the head and thorax are joined together as a cephalothorax. Q: The head, thorax, and abdomen comprise what type of body structure, possessed by arthropods? Choices: - vertebrate - elongated - permeable - segmented A:
Ans: segmented
(Q).
Answer the following question given this paragraph: Blood with wastes enters each kidney through an artery, which branches into many capillaries. After passing through capillaries and being filtered, the clean blood leaves the kidney through a vein. Q: After passing through capillaries and being filtered, clean blood leaves what organ through a vein? Choices: - pancreas - liver - heart - kidney A:
(A).
kidney
Ques:Answer the following question given this paragraph: Chapter 22 1 Figure 22.8 The extracellular matrix and outer layer of cells protects the inner bacteria. The close proximity of cells also facilitates lateral gene transfer, a process by which genes such as antibiotic resistance genes are transferred from one bacterium to another. And even if lateral gene transfer does not occur, one bacterium that produces an exo-enzyme that destroys antibiotic may save neighboring bacteria. 3 Figure 22.19 D 4 A 6 A 8 B 10 B 12 A 14 B 16 C 18 B 20 D 22 D 24 B 25 As the organisms are non-culturable, the presence could be detected through molecular techniques, such as PCR. 27 Responses will vary. A possible answer is: Bacteria contain peptidoglycan in the cell wall; archaea do not. The cell membrane in bacteria is a lipid bilayer; in archaea, it can be a lipid bilayer or a monolayer. Bacteria contain fatty acids on the cell membrane, whereas archaea contain phytanyl. 29 Responses will vary. In a deep-sea hydrothermal vent, there is no light, so prokaryotes would be chemotrophs instead of phototrophs. The source of carbon would be carbon dioxide dissolved in the ocean, so they would be autotrophs. There is not a lot of organic material in the ocean, so prokaryotes would probably use inorganic sources, thus they would be chemolitotrophs. The temperatures are very high in the hydrothermal vent, so the prokaryotes would be thermophilic. 31 E. coli colonizes the surface of the leaf, forming a biofilm that is more difficult to remove than free (planktonic) cells. Additionally, bacteria can be taken up in the water that plants are grown in, thereby entering the plant tissues rather than simply residing on the leaf surface. Q: Why would prokaryotes be chemotrophs instead of phototrophs in a deep-sea hydrothermal vent? Choices: - too cold - too much light - too much heat - lack of light A:

Ans:lack of light
Answer the following question given this paragraph: Life on Earth is based on carbon. A possible explanation is that no other element in the periodic table forms compounds that are so diverse in their chemistry and physical properties. Discuss the chemistry of carbon with regard to. Q: What element on the periodic table forms the most diverse compounds? Choices: - helium - oxygen - hydrogen - carbon A:
carbon