八年级生物上册期中考试复习提纲（Eight grade biology book on the midterm review outline）.docVIP

八年级生物上册期中考试复习提纲（Eight grade biology book on the midterm review outline） Eight grade biology book on the midterm review outline I. animals living in water 1, there are about 1 million 500 thousand known animals, divided into vertebrate and invertebrate according to whether there are two kinds. According to the living environment, it is divided into land life, animal, aquatic life, animal and air life animal. The 2 most common, aquatic animal is fish, in addition, there is a coelenterate animal, such as sea anemones, corals; the soft animal, such as squid, octopus; the crustacean animal, such as shrimp, crab; the dolphin (mammals), turtles and other aquatic animal (reptiles). 3, fish adapted to life in the water the two most important features: 1 can swim to get food and defense against predators. Breathe in the water. 4, four fish: carp, silver carp, grass carp and bighead. 5, fish are lower vertebrates. 6, the shape of the fish spindle shape, its role is: to reduce swimming resistance, suitable for swimming. Fish can be divided into three parts: head, trunk, head and tail. 8, the fish in swimming depends mainly on the swing body _ trunk and caudal _ _ hit water flow generated motivation, other fins play a supporting role. The fish in the movement, dorsal fin, pectoral and pelvic fins, both maintain a balanced role, decided the direction of movement of the fish tail effect. 9. The sense organ of fish is the lateral line (sensing water flow and measuring direction). 10, fish gills is bright red, because it contains rich capillaries, gill filament is many and fine, and its role is greatly increased the contact area with water, promote blood and external gas exchange. 12, the water from the fish mouth ___ __ into gills, followed by posterior operculum (gill hole outflow). In the water through the gills, _ _ oxygen dissolved in the water into the gills __ capillary __, and _ _____ gill by carbon dioxide emissions into the water; so by the flow of water from the mouth and