Chordate Cladogram Section 30-1 Mammals Birds Reptiles Amphibians Fishes Nonvertebratechordates Invertebrate ancestor
Nonvertebrate Chorodate • Choradate • Dorsal hollow nerve cord • Notochord • Pharyngeal pouches • Tail that extend beyond anus • Nonvertebrate Chorodates • Tunicates and Lancelets
The Generalized Structure of a Chordate Notochord Muscle segments Hollownerve cord Anus Tail Mouth Pharyngeal pouches Section 30-1
3 Characteristics of all Vertebrates • Endoskeleton. • Supports larger animal size. • Grows with animal (No molting!) • Backbone and cephalization. • Well-developed brain with sensory organs. • Earliest vertebrates were called ostracoderms. • 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 Chordates Section 33-2 Body Temperature (°C) Environmental Temperature (°C)
Diversity of Chordates Section 33-1
Characteristics of Fishes • 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 Fish Pyloriccecum Esophagus Stomach Kidney Brain Swimbladder Vertebra Gills Spinalcord Muscle Mouth Operculum Heart Anus Urinarybladder Reproductiveorgan Pancreas Gallbladder Intestine Liver Section 30-2
Circulation in a Fish Oxygen-rich blood Oxygen-poor blood Section 30-2 Gills Brain and head circulation Sinus Venosus Atrium Oxygen-poor bloodfrom the veins collects in the sinusvenosus. Blood enters theatrium and flowsto the ventricle. Body muscle circulation Ventricle Digestive system circulation Bulbus Arteriosus The ventricle pumps blood into the bulbus arteriosus. Heart The bulbus arteriosus moves blood into the ventral aorta and toward the gills.
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 fishes?)
Rainbow Cut Throat
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 Frog Section 30-3 Adult Frog Adults are typically ready tobreed in about one to two years. Young Frog Frog eggs are laid in water and undergo external fertilization. The eggs hatch into tadpoles a few days to several weeks later. Fertilized Eggs 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 The amnion is a fluid-filled sac that surrounds and cushions the developing embryo. It produces a protected, watery environment. The allantois stores the waste produced by the embryo. It also serves as a respiratory organ. The chorion regulates the transport of oxygen from the surface of the egg to the embryo and the transport of carbon dioxide, one product of respiration, in the opposite direction. This baglike structure contains a yolk that serves as a nutrient-rich food supply for the embryo. Section 31-1 Amnion Allantois Embryo Chorion Yolk sac Shell
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 When a bird eats, food moves down the esophagus and is stored in the crop. Heart 1 Kidney Crop Air sac Liver Moistened food passes to the stomach, a two-part chamber. The first chamber secretes acid and enzymes. The partially digested food moves to the second chamber, the gizzard. 2 Firstchamberof stomach Pancreas Large intestine Gizzard Smallintestine Undigested food is excreted through the cloaca. Cloaca 5 The muscular walls of the gizzard squeeze the contents, while small stones grind the food. 3 As digestion continues, the food moves through the intestines. 4
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 Canines are pointed teeth. Carnivores use them for piercing, gripping, and tearing. In herbivores, they are reduced or absent. 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. Section 32-1 CARNIVORE HERBIVORE Jawjoint Jaw joint Horse Wolf
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).
The Placenta Section 39-4
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 Chordates Respiration Circulation Excretion Response Non- vertebrate Chordates Gills and diffusion No true chambers Gills andgill slits Simple; mass of nerve cells Gills/air sacs Single loop; 2 chambers Kidney andgills Cephalization; small cerebrum Simple lungs and skin Double loop; 3 chambers Kidney andgills Cephalization; small cerebrum Lungs Double loop; 3 chambers Kidney Cephalization; small cerebrum Lungs (tubes and air sacs; one-way flow) Double loop; 4 chambers Kidney Cephalization; large cerebrum Lungs (alveoli) Double loop; 4 chambers Kidney Cephalization; large cerebrum Gills and diffusion No true chambers Gills andgill slits Simple; mass of nerve cells Birds Function Fishes Amphibians (adult) Mammals Reptiles
The Circulatory Systems of Vertebrates Section 33-3 Single-LoopCirculatory System Double-Loop Circulatory System FISHES MOST REPTILES CROCODILIANS, BIRDS,AND MAMMALS
Compare/Contrast Table continued Amphibians (adult) Limbs stick out sideways; muscles and ligaments External fertilization Ectothermic Section 33-3 Comparing Functions of Chordates Muscles,no bones External fertilization Ectothermic Movement Reproduction TemperatureControl Muscles on either side of backbone External fertilization Ectothermic Limbs point directly toward ground; muscles and ligaments Internal fertilization; shelled egg Ectothermic Upper limbs are wings; 2 feet; muscles and ligaments Internal fertilization; shelled egg Endothermic 2 or 4 legs; walk with legs straight under them; muscles and ligaments Internal fertilization and development Endothermic Birds Function Non- vertebrate Chordates Fishes Amphibians (adult) Mammals Reptiles
The Digestive Systemsof Vertebrates Section 33-3 Shark Salamander Lizard Pigeon Cow Esophagus Stomach Intestine Liver Gallbladder Pancreas Cloaca Crop Gizzard Cecum Rectum
Figure 35-2 Human Organ Systems Part I Section 35-1 Nervous System Integumentary System Skeletal System Muscular System Circulatory System
Figure 35-8 The Synapse Section 35-2 Direction of Impulse Dendrite of adjacent neuron Axon Receptor Vesicle Axon terminal Synaptic cleft Neurotransmitter
Cerebrum Thalamus Pineal gland Hypothalamus Cerebellum Pituitary gland Pons Medulla oblongata Spinal cord Figure 35-9 The Brain Section 35-3
Olfactory (smell) bulb Taste sensory area Olfactory nerve Thalamus Cerebral cortex Smell receptor Nasal cavity Smell sensory area Taste bud Taste pore Taste receptor Sensory nerve fibers The Senses of Smell and Taste Section 35-4
Vitreous humor Muscle Lens Fovea Aqueous humor Cornea Pupil Optic nerve Iris Blood vessels Ligaments Retina Choroid Sclera Figure 35-14 The Eye Section 35-4