Chapter 14 Fish Amphibians Reptiles Section 1 Chordates

Chapter 14 -Fish, Amphibians, & Reptiles

Section 1 -Chordates & Vertebrates Chordates 1. Notochord: the structure that becomes the backbone in vertebrates. 2. Postanal tail-a muscular structure at the end of the developing chordate. 3. Nerve cord: tube like structure that develops into the brain and spinal chord. 4. Gill slits-in developing chordates, the paired openings found in the area between the mouth and digestive tube.

Section 1 -continued Vertebrates 1. Have all of the above characteristics 2. Endoskeleton-internal skeleton/framework made up of bone and/or cartilage. 3. Vertebrae-the backbone surrounds and protects the spinal nerve cord. 4. Protective skin -covers the vertebrate (hair, feathers, and scales)

Types of Vertebrates n Jawless fish- lamprey, hagfish n Cartilaginous Fish- shark, ray, skate n Bony Fish- salmon, bass, sea horse, nemo n Amphibians- frog, toad, salamander n Reptiles- turtle, lizard, snake, crock & alli n Birds- stork (how else do you think you got here), eagle, turkey, duck, ostrich n Mammals- human, whale, bat, mouse, lion, cow, otter

Circle graphs n We will construct a circle graph from the data shown on page 400, showing what percentages of species belongs to each vertebrate group.

Fish-section 2 n Fish Characteristics 1. All fish are ectotherms-cold blooded 2. Live in fresh and salt water 3. Most have scales 4. A streamlined shape, muscular tail, and fins

Fish n Fish have highly developed sensory systems n Have a 2 -chambered heart (oxygen-filled blood mixes with carbon dioxide-filled blood) n Have gills for the exchange of CO 2 & O 2

Types of Fish n Jawless Fish- have round, toothed mouths and long, tubelike bodies covered with scale- less, slimy skin. n Cartilaginous Fish- have skeletons made of cartilage (sharks, rays, skates), have scales n Bony Fish- about 95% of all fish ~ swim bladder ~is an air sac that allows the fish to adjust its density in response to the density of the surrounding water

Importance of Fish n They provide food for many animals and humans. n Fish farming and commercial fishing“fishing is central to the livelihood and food security of some 200 million people, especially in the developing world, while one out of five depends on fish as the primary source of protein. ”

What is the disadvantage of having a -chambered heart? two

FYI n When referring to many individuals of a a single species, the plural is fish. When referring to several individuals of more than on species, the plural is fishes. n African lung fish

Summarize

Amphibians-section 3 n Amphibian means “double life”-they spend part of their lives in water and part on land. n Examples: Frogs, toads and salamanders n They are ectotherms (their body temperature changes when the temperature of their surroundings changes). n Hibernation (inactivity during cold weather) vs. Estivation (inactivity during the hot, dry months

Amphibian body systems n Respiration-oxygen and carbon dioxide are exchanged through the skin and the mouth lining (skin is moist and thin), most also have small-simple saclike lungs. n Circulation- 3 chambered heart, where there is limited mixing of oxygen filled and carbon dioxide filled blood.

body systems-con’t n Reproduction- amphibians depend on water for reproduction. Most females lay the eggs in water, (some tree frogs-in a thick gelatin on the underside of leaves). n Development- most go through metamorphosis (eggs, tadpoles, adults). As tadpoles grow into frogs and toads, they develop legs, lungs, and a three-chambered heart.

OUT Eyewitness video-Amphibians n What adaptations do amphibians have to live 1. 2. 3. 4. on land? Breathing. Support. Surviving winter. Reproduction-

Importance of Amphibians n Help keep insect populations in control n They are a source of food for other animals n Humans use the toxin from poison arrow frogs for hunting n Researchers are using amphibians in regeneration studies in hope of developing new ways of treating humans who have lost limbs. n Biological Indicators-are species whose overall health reflects the health of a particular ecosystem

Reptiles ~Reptile characteristics~ n Reptiles are ectotherms w/thick, dry, waterproof skin covered w/scales n They breathe w/lungs and have a 3 chambered heart. n Use internal fertilization and lay eggs w/shells; the amniotic egg provides a complete environment for the embryo.

Three Groups of Reptiles n Lizards and Snakes Have jaws that unhinge so they can swallow their prey whole.

Turtles n Have a two-part shell made of hard, bony plates for protection against predators.

Crocodiles and Alligators Are lizard-shaped with large, deep scales on their backs. shape They are among the few reptiles that care for their young. ~Crocks~ Have a narrow head with a triangular snout ~Alligators~ n U-shaped nose n Top jaw-overlaps bottom jaw n n n

Out Eyewitness video-Reptiles n Adaptations for Land 1. Prevent water loss 2. Climbing, running 3. Breathing 4. Circulation 5. Reproduction-

In n We are family-section 1 transparency

IN n Why are tunicates and lancelets classified as chordates?

In n The largest living fish is the Whale Shark. 15 -18 meters Up to 10 tons n The smallest freshwater fish is the dwarf pygmy goby which measures ______ long. n A. nine meters n B. nine centimeters n C. nine millimeters

In Name 3 classes of fish and give an example of each. Give me a second. . I’m thinking!

In n. What kind of environment do frogs live in? n. Why might frogs be sensitive to pollution in air and water? n (http: //www. amphibiaweb. org

Out n Ectotherms do not perspire or pant. How do they control body temperature (you can use an example if that helps).

IN n Why are amphibians considered to be biological indicators?

Answer to In n They live on land, reproduce in water, and absorb gases from the air through their skin. They are sensitive to chemical changes on land, in water, and in the air.

IN n. Explain the difference between hibernation and estivation, use an example to help explain.