The latter are throat<span> teeth. Most predacious fishes swallow their prey whole, and the teeth are used for grasping and holding prey, for orienting prey to be swallowed (head first) and for working the prey toward the esophagus. There are a variety of tooth types in fishes.</span>
Answer:
Troposphere is the lowest layer of Earth’s atmosphere that has undergone a large increase in temperature due to the presence of greenhouse gases.
Explanation:
Troposphere (0 to 12 km) where we live is the lowest layer of earth's atmosphere, which is closest to the earth's surface contains half of the atmosphere. Here most clouds are found and almost all weather occurs. Atmosphere contains approximately 78% of nitrogen , 21% of oxygen and 0.9% of argon. Gases like carbon dioxide, nitrous oxides, methane, ozone and the water vapor constitutes the rest of the atmosphere. Many small particles called aerosols are also there which include dust, spores, pollen, volcanic ash, smoke etc.The greenhouse effect is a natural phenomenon that keeps the temperature on the earth suitable for supporting life. The greenhouse gases includes both natural and man-made gases like carbon dioxide
, methane, nitrous oxide, chlorofluorocarbons, hydrochlorofluorocarbons, ozone, water vapour. They absorb radiation in the atmosphere and create the green house effect. The thermal infrared radiation emitted by the Earth’s surface and the atmosphere is absorbed by greenhouse gases. They trap heat within the surface-troposphere system preventing it from escaping back into space. This is called the greenhouse effect, which increases the temperature of the lower atmosphere.The increase in the atmospheric concentrations of greenhouse gases due to human activity has caused an increase in the natural greenhouse effect. As a result, the atmosphere is trapping too much heat which increases the temperature of the Earth.
Answer:
The spindle, shown in figure below, consists of fibers made of microtubules. the spindle starts to form during prophase of mitosis kinetochores on the spindle attach to the centromeres of sister chromatids.
Explanation: Chromosomes line up at the metaphase plate under tension from the mitotic spindle.