The Generalized Structure of Section 30-1a Chordate Notochord Muscle segments Hollow nerve cord Anus Tail Mouth Pharyngeal pouches
3 Characteristics of all Vertebrates1. Endoskeleton. Supports larger animal size. Grows with animal (No molting!) Backbone and cephalization. Well-developed brain with sensory organs. Earliest vertebrates were called ostracoderms.3. Closed circulatory system with multi-chambered heart. 3- or 4-chambered heart allows blood to be separated into oxygenated or deoxygenated. More efficient delivery of oxygen to the body.
Endotherms and Ectotherms• Ectotherm: Temperature is regulated by external environment. – Fish, amphibians, reptiles• Endotherm: Body temperature is regulated by internal processes. – Mammals, birds
Temperature Control in ChordatesSection 33-2 Body Temperature (°C) Environmental Temperature (°C)
Diversity of ChordatesSection 33-1
Characteristics of fish• Live in water.• Overlapping scales that cover skin.• Mucus coat (reduces friction when swimming).• Swim bladder (buoyancy, sharks don’t have one). – Why do many sharks never stop swimming?• Lateral line system (detects vibrations in water).• Gills (blood and water flow in opposite directions; more efficient oxygen absorbtion and CO2 release. OPERCULA: opening and closing flaps; sharks)
The Anatomy of a FishSection 30-2 Pyloric cecum Esophagus Stomach Kidney Swim Brain Vertebra Spinal Gills Muscle bladder cord Mouth Operculum Anus Heart Urinary bladder Reproductive Pancreas Gallbladder organ Intestine Liver
Circulation in a Fish Section 30-2 Gills Brain and head Sinus Venosus Atrium circulation Oxygen-poor blood Blood enters theBody from the veins collects atrium and flowsmuscle in the sinus to the ventricle.circulation venosus. Digestive Ventricle Bulbus Arteriosus system Heart The ventricle pumps circulation blood into the bulbus The bulbus arteriosus arteriosus. moves blood into the ventral aorta and toward the gills. Oxygen-rich blood Oxygen-poor blood
Fish: Life Cycle• Varied strategies. – Sharks: internal fertilization. Salmon: external.• Generally, lay many more eggs than they need. – Many are never fertilized. – Many more are fertilized than the environment can support. (Why? Isn’t this wasted effort on the part of the fish?)
Characteristics of Amphibians• Live both in water and on land.• Four strong limbs.• Nictating membrane: see through second eyelid. Why is this helpful on both land and in the water?• Tympanic membrane: hearing. Land? Water?
Amphibians: Energy and Wastes• A frog’s skin “breathes” – it must be kept moist.• 3-Chambered Heart, Double-looped circulatory system. – What is that? Why is that a good thing?• Metamorphisis: teeth/jaws, gills turn into lungs, circulatory system changes• Kidneys regulate the amount of water in the frog. – In water excrete, on land retain.
The Life Cycle of a FrogSection 30-3 Adult Adults are typically ready to Frog breed in about one to two years. Young Frog eggs are laid in water and The eggs Frog undergo external fertilization. hatch into tadpoles a Fertilized Eggs few days to several weeks later. Tadpoles Tadpoles gradually grow limbs, lose their tails and gills, and become meat-eaters as they develop into terrestrial adults.
Characteristics of Reptiles• Dry, scaly skin (prevents evaporation). – Keratin: A hard, water-resistant protein (human hair and fingernails, bird feathers).• Usually carnivores.• Separated 3-chambered heart (crocodiles have 4 chambers).• Ectotherms. – How does a reptile regulate its body temperature?
The Amniotic Egg (Figure 26.4)• Embryo: connected to Yolk by a stalk.• Yolk: food source.• Amnion: fluid that protects the embryo.• Chorion: regulates gas exchange.• Shell: Waterproofs, protects. The shell is porous (gas can exchange through it).• Allantois: stores wastes.
The Amniotic Egg Section 31-1Amnion Embryo AllantoisThe amnion is a fluid-filled sac The allantois stores thethat surrounds and cushions waste produced by thethe developing embryo. It embryo. It also servesproduces a protected, watery as a respiratory organ.environment.ChorionThe chorion regulatesthe transport ofoxygen from thesurface of the eggto the embryo andthe transport ofcarbon dioxide,one product ofrespiration, in theopposite direction. Yolk sac This baglike structure contains a yolk that serves as a nutrient-rich Shell food supply for the embryo.
Characteristics of Birds• Adaptations center around flight… – Light-weight bones: hollow, but have cross braces. – Shape of a bird’s wings gives lift. – Fused bones (ligaments are heavy). – Massive flight muscles (Pectoralis: 25% of weight).• Shape of the wings gives lift.• The one reptilian characteristic of birds is their scale-covered legs.
The Digestive System of a Pigeon Section 31-2 Brain Esophagus Lung 1 When a bird eats, Heart food moves down Crop Kidney the esophagus and Air sac is stored in the crop. Liver2 Moistened food passes to the stomach, a two-part chamber. First The first chamber secretes acid chamber Pancreas and enzymes. The partially of stomach Large intestine digested food moves to the Gizzard Small second chamber, the gizzard. Cloaca 5 Undigested food is intestine excreted through the cloaca. 3 The muscular walls 4 As digestion continues, of the gizzard squeeze the food moves through the contents, while the intestines. small stones grind the food.
You Eat Like A Bird…• Endotherms – requires a lot of energy to maintain their high metabolism.• Feathers – trap body heat.• Unique respiratory system – air flows one-way.• Crop Gizzard Intestines. – Figure 26.18.
Blue Jay- Mr. Phillips Favorite Bird• Toronto Blue Jays World Series 1992-1993 Champions
Characteristics of Mammals• Endotherms – hair.• Mammary glands – produce milk.• Large, well-developed brains.• 4-chambered heart, double-looped circulatory system.
Variety of Mammals• Size – Smallest: shrew (weighs less than a dime) – Largest: whale (100,000 kg; 32 elephants)• Speed – Slowest: Two-toed sloth (1 meter/15 seconds) – Fastest: Cheetah (400 meters/15 seconds) – Humans (150 meters/15 seconds)• Environments
Mammals: Movement and Energy • High-speed running: long bones and flexible hip and shoulder joints. • Eat a variety of foods: different teeth structures. • Diaphram: More gas exchange. • Air sacs: increased surface area for gas exchange.
The Jaws and Teeth of Mammals Section 32-1 CARNIVORE HERBIVORE Canines are pointed teeth. Carnivores use them for piercing, gripping, and tearing. In herbivores, they are reduced or absent. JawJaw joint joint Horse Wolf Chisel-like incisors are used for cutting, gnawing, and grooming. Molars crush and grind food. The ridged shape of the wolf’s molars and premolars allows them to interlock during chewing, like the blades of scissors. The broad, flattened molars and premolars of horses are adapted for grinding tough plants.
Mammals: Types of Life Cycles• Monotremes: Reproduce by laying eggs (duck-billed playtpus).-• Marsupials: Give birth to small, immature young that then further develop inside the mother’s external pouch (kangaroo).• Placental mammals: Babies develop inside the mother’s body (95% of all mammals).
Section 39-4 The Placenta
The Success of Mammals• Well-developed cerebrum: The largest part of the brain; makes processing information and learning possible.• Care of the Young: Development inside the mother; care of the young for the first year(s) of their life.
Compare/Contrast Table Section 33-3 Comparing Functions of ChordatesFunction Non- fish Amphibians Reptiles Birds Mammals vertebrate (adult) ChordatesRespiration Gills and Gills/air sacs Simple lungs Lungs Lungs (tubes Lungs diffusion and skin and air sacs; (alveoli) one-way flow)Circulation No true Single loop; 2 Double loop; Double loop; Double loop; Double loop; chambers chambers 3 chambers 3 chambers 4 chambers 4 chambersExcretion Gills and Kidney and Kidney and Kidney Kidney Kidney gill slits gills gillsResponse Simple; mass Cephalization; Cephalization; Cephalization; Cephalization; Cephalization; of nerve cells small small small large large cerebrum cerebrum cerebrum cerebrum cerebrum
The Circulatory SystemsSection 33-3 of Vertebrates Single-Loop Double-Loop Circulatory System Circulatory System fish MOST REPTILES CROCODILIANS, BIRDS, AND MAMMALS
Compare/Contrast Table Section 33-3 continued Comparing Functions of ChordatesFunction Non- fish Amphibians Reptiles Birds Mammals vertebrate Amphibians (adult) Chordates (adult)Movement Muscles, Muscles on Limbs stick Limbs point Upper limbs 2 or 4 legs; no bones either side of out sideways; directly are wings; 2 walk with legs backbone muscles and toward feet; muscles straight under ligaments ground; and ligaments them; muscles and muscles and ligaments ligamentsReproduction External External External Internal Internal Internal fertilization fertilization fertilization fertilization; fertilization; fertilization shelled egg shelled egg and developmentTemperature Ectothermic Ectothermic Ectothermic Ectothermic Endothermic EndothermicControl
The Digestive Systems Section 33-3 of Vertebrates Shark Salamander Lizard Pigeon CowEsophagusStomachIntestineLiverGallbladderPancreasCloacaCropGizzardCecumRectum