Shark Test
暂无描述。系统推荐的高质量记忆内容，适合每天坚持背诵学习。
卡片预览 (24 张)
Some vertebrates are made of cartilage or
Bone
What are the largest group of vertebrates?
Fish
What are the types of marine fish?
Agnatha (jawless fish) Chondrichthyes (cartilaginous fish) Osteichthyes (bony fish)
Examples of Agnatha:
Hagfish Lampreys
Muscular circular mouth Long, cylindrical body Lack fins & scales
Agnatha
Feed on dead and dying fish (scavengers) Live in burrows in soft sediments
Hagfishes
Parasites Return to freshwater to breed
Lamprey
Examples of Chondrichthyes (cartilaginous fish)
Sharks Skates Rays Ratfish
Examples of Osteichthyes (bony fish):
Lobe-finned fishes Ray-finned fishes
What fish are considered more advanced?
Chondrichthyes and Osteichthyes
Characteristics of more advanced fish:
Highly efficient gills Scales Paired fins Many types of jaws Lateral line and other sensory organs Streamlined body
1000 species 5-7 gill slits Spiraled Claspers in males
Chondrichthyes
Openings on the head used to bring water directly in for respiration
Spiracles
Projections of the anal fin in makes used in copulation
Claspers
Why are the number of sharks decreasing?
Meat Oil Skin Fins
Sensory organ used to detect electrical currents when sharks are close to an object
Organ of Lorenzini
Thin tissue that covers eye for protection
Nicticating membrane
Live birth
Vivipary
Lay egg cases
Ovipary
Internalized egg that hatches inside female before the young are expelled from the female
Ovovivipary
How many species of sharks?
350
Most sharks are? But some are
Carnivorous; planktonic
Prefer shallow, warm water Will travel into fresh water Short, blunt snout 7-11 ft
Bull shark
Stay in shallow water
Sand tiger shark