Q: Q: What is the hinged structure attached to the cranium that allows an animal to grasp and tear its food? Read this paragraph and choose the correct option from the provided answers: Gnathostomes: Jawed Fishes Gnathostomes or "jaw-mouths" are vertebrates that possess jaws. One of the most significant developments in early vertebrate evolution was the development of the jaw, which is a hinged structure attached to the cranium that allows an animal to grasp and tear its food. The evolution of jaws allowed early gnathostomes to exploit food resources that were unavailable to jawless fishes. Early gnathostomes also possessed two sets of paired fins, allowing the fishes to maneuver accurately. Pectoral fins are typically located on the anterior body, and pelvic fins on the posterior. Evolution of the jaw and paired fins permitted gnathostomes to expand from the sedentary suspension feeding of jawless fishes to become mobile predators. The ability of gnathostomes to exploit new nutrient sources likely is one reason that they replaced most jawless fishes during the Devonian period. Two early groups of gnathostomes were the acanthodians and placoderms (Figure 29.10), which arose in the late Silurian period and are now extinct. Most modern fishes are gnathostomes that belong to the clades Chondrichthyes and Osteichthyes. Choices: - tooth - neck - throat - jaw A:
A: jaw

Q: Q: What is the major cause of outdoor air pollution? Read this paragraph and choose the correct option from the provided answers: The major cause of outdoor air pollution is the burning of fossil fuels. Fossil fuels are burned in power plants, factories, motor vehicles, and home heating systems. Ranching and using chemicals such as fertilizers also cause outdoor air pollution. Erosion of soil in farm fields, mining activities, and construction sites adds dust particles to the air as well. Some specific outdoor air pollutants are described in Table below . Choices: - electric lines - agricultural equipment - manufacturing industry - burning fossil fuels A:
A: burning fossil fuels

Q: Q: What is the first step in the breakdown of glucose to extract energy for cellular metabolism? Read this paragraph and choose the correct option from the provided answers: 7.2 | Glycolysis By the end of this section, you will be able to: Describe the overall result in terms of molecules produced in the breakdown of glucose by glycolysis Compare the output of glycolysis in terms of ATP molecules and NADH molecules produced You have read that nearly all of the energy used by living cells comes to them in the bonds of the sugar, glucose. Glycolysis is the first step in the breakdown of glucose to extract energy for cellular metabolism. Nearly all living organisms carry out glycolysis as part of their metabolism. The process does not use oxygen and is therefore anaerobic. Glycolysis takes place in the cytoplasm of both prokaryotic and eukaryotic cells. Glucose enters heterotrophic cells in two ways. One method is through secondary active transport in which the transport takes place against the glucose concentration gradient. The other mechanism uses a group of integral proteins called GLUT proteins, also known as glucose transporter proteins. These transporters assist in the facilitated diffusion of glucose. Glycolysis begins with the six carbon ring-shaped structure of a single glucose molecule and ends with two molecules of a three-carbon sugar called pyruvate. Glycolysis consists of two distinct phases. The first part of the glycolysis pathway traps the glucose molecule in the cell and uses energy to modify it so that the six-carbon sugar molecule can be split evenly into the two three-carbon molecules. The second part of glycolysis extracts energy from the molecules and stores it in the form of ATP and NADH, the reduced form of NAD. Choices: - mutation - mitosis - photosynthesis - glycolysis A:
A: glycolysis

Q: Q: The soil beneath a deciduous forest is called what? Read this paragraph and choose the correct option from the provided answers: The soil beneath a deciduous forest is a pedalfer. These soils are very fertile. Choices: - cocklebur - forest floor - trichina - pedalfer A:
A: pedalfer