8. ANIMAL KINGDOM INTRODUCTION The Animal Kingdom includes about 40 different phyla of organisms that are all heterotrophic, multicellular, eukaryotes that lack cell walls. Animals are believed to have descended from a protozoan (Kingdom Protista) ancestor. Although variable in form and complexity, most animals have muscle and nervous tissue. The other features of animals vary, and are used to distinguish the different phyla. Here is a review of the basic classification system used for all living organisms: DOMAIN KINGDOM TRAIT Archaea Not Used Prokaryotic cells, found in extreme environments Bacteria Not Used Prokaryotic cells, bacteria w/unique biochemical features Eukarya Protist Eukaryotic cells, single cell organisms and some simple multicellular organisms, autotrophic or heterotrophic, motile or non-motile Eukarya Plant Eukaryotic cells, multicellular, autotrophic, non-motile Eukarya Fungi Eukaryotic cells, multicellular, heterotrophic-absorptive, non- motile Eukarya Animal Eukaryotic cells, multicellular, heterotrophic-ingestive, generally motile GOALS AND OBJECTIVES 1. For each animal we look at be able to answer the following questions: a. What is the animal’s habitat: terrestrial, aquatic (freshwater or marine), or amphibious? b. What level of organization does it have: cellular, tissue, or organ system? c. What type of symmetry does the animal’s body exhibit: radial, bilateral or asymmetrical? d. What type of digestive system does the animal possess: none, complete or incomplete? e. What type of gas exchange surface does the animal have: cells, skin, gills, lungs, or tracheae? f. What type of circulatory system does it have: none, open, or closed? g. Understand how animals use muscles to move. Know an example of a phylum whose members move using a hydrostatic skeleton, an endoskeleton and an exoskeleton. 2. Know the unique and distinguishing characteristics of the Animal Kingdom. 3. Know the characteristics that distinguish each animal phylum. Be able to identify examples of each phylum. For selected phyla you may be asked to identify examples of the classes and distinguish their characteristics. 4. Be able to answer the questions asked in this handout. 10.09 8-1
Transcript
8. ANIMAL KINGDOM INTRODUCTION
The Animal Kingdom includes about 40 different phyla of organisms that are all heterotrophic, multicellular, eukaryotes that lack cell walls. Animals are believed to have descended from a protozoan (Kingdom Protista) ancestor. Although variable in form and complexity, most animals have muscle and nervous tissue. The other features of animals vary, and are used to distinguish the different phyla. Here is a review of the basic classification system used for all living organisms:
DOMAIN KINGDOM TRAIT Archaea Not Used Prokaryotic cells, found in extreme environments
Bacteria Not Used Prokaryotic cells, bacteria w/unique biochemical features
Eukarya Protist Eukaryotic cells, single cell organisms and some simple multicellular organisms, autotrophic or heterotrophic, motile or non-motile
Eukarya Animal Eukaryotic cells, multicellular, heterotrophic-ingestive, generally motile
GOALS AND OBJECTIVES 1. For each animal we look at be able to answer the following questions:
a. What is the animal’s habitat: terrestrial, aquatic (freshwater or marine), or amphibious? b. What level of organization does it have: cellular, tissue, or organ system? c. What type of symmetry does the animal’s body exhibit: radial, bilateral or asymmetrical? d. What type of digestive system does the animal possess: none, complete or incomplete? e. What type of gas exchange surface does the animal have: cells, skin, gills, lungs, or tracheae? f. What type of circulatory system does it have: none, open, or closed? g. Understand how animals use muscles to move. Know an example of a phylum whose members move using a hydrostatic skeleton, an endoskeleton and an exoskeleton.
2. Know the unique and distinguishing characteristics of the Animal Kingdom.
3. Know the characteristics that distinguish each animal phylum. Be able to identify examples of each phylum. For selected phyla you may be asked to identify examples of the classes and distinguish their characteristics.
4. Be able to answer the questions asked in this handout.
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GOALS AND OBJECTIVES continued As you go through this lab you will examine the following characteristics of animals: Habitat Where does the animal live? Is it terrestrial or aquatic? Freshwater or
marine? Maybe amphibious?
Organization All animals are multicellular and may exhibit one of three different levels of organization: cellular level, tissue level, or organ system level. An organism with a cellular level of organization has different cells specialized for particular functions, but does not have tissues or organs. An organism with tissue level organization has specialized cells that work together for a common function (for example, muscle tissue or nervous tissue). Finally, organisms with organ system level organization have tissues that work together for a common function to produce organs (for example, a stomach or heart). These organs may then form organ systems such as the digestive or circulatory system.
Symmetry When an animal can be divided into equivalent halves it is symmetrical. In bilateral symmetry there is only one way to divide the animal so that both halves are the same size and shape. An animal with radial symmetry can be divided in more than one way. Some animals are asymmetrical showing no symmetry.
Digestion Simple animals have an incomplete digestive system with one opening that serves as both a mouth and an anus. Other animals have a complete digestive system with two openings (mouth and anus) at opposite ends of a tube that is modified along its length for specialized functions.
Gas Exchange A gas exchange surface is used to exchange CO2 (a waste product of a cell) for O2 (needed for cellular function). Simple animals exchange gases through their surface. Many aquatic animals have gills, a complex of filaments where gases exchange. Terrestrial animals usually have internal lungs protecting the gas exchange surface from drying out. An alternative for some terrestrial animals is a series of tubes called tracheae that bring oxygen from the air directly to all the cells of the animal.
Circulation Most animals use a circulatory system to transport nutrients to all of their cells and to carry away wastes. However, not all animals need a circulatory system. If an animal’s body is only a few cell layers thick, it may be able to simply transport nutrients and wastes by diffusion. Most, but not all, animals that have bodies made of numerous cell layers have a circulatory system. A circulatory system may be an open circulatory system, meaning that the blood vessels are open ended and the blood flows freely among the cells, or a closed circulatory system, meaning that the blood vessels make a continuous loop and the blood remains contained within them.
Skeletons and One of the features we associate with animals is their mobility. Most animals Movement move using muscle tissue, which is made of cells that work together to contract. Muscles
need to pull against hard parts. The hard part in an organism can be a hydrostatic skeleton (fluid filled cavity), an exoskeleton (a hard covering on the outside) or an endoskelton (hard parts such as bones inside the body).
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Body Plan
No symmetry – no directionality An animal with this design grows in all directions, usually on the surface of something else, and is non-motile. These kinds of animals typically have no particular defining form. Each part of the organism can act independently of the other parts. Radial symmetry – radial directionality An animal with radial symmetry can be divided into two equal-looking halves by any cut through the long axis, like cutting a pie or a ball in half. These animals move or react to the environment equally in all directions. This design does not have a head and a tail, and does not usually search for and locate its food like the next group does. To get food, this type of animal is usually stationary or is carried passively by water currents, capturing food that passes by. Bilateral symmetry – one directionality Bilateral means “two sides” and there is only one way to cut animals with bilateral symmetry into two equal-looking halves. An animal with this body plan responds to its environment by using directional movement. Its head end has a concentration of sense organs, and it travels through the environment head first, orienting to different stimuli such as light or food. Bilateral animals are thought to be the first active predators to evolve. Skeletons and Movement One of the features we associate with animals is their mobility. Most animals move using muscle tissue, which is made of cells that work together to contract. Muscles can only get shorter when they contract, and in fact they must be stretched by something else, such as another muscle or an elastic structure to become longer again. In order to use muscles to move, an animal needs two things: 1) a rigid structure for the muscles to pull on, and 2) opposing sets of muscles to do the pulling. Muscles can only contract, so how do you use opposing muscles to move? Raise and lower your right hand by bending your elbow while feeling the contraction of your upper arm muscles with your left hand. Be able to explain how your biceps and triceps muscles work together to move your arm.
ANIMAL KINGDOM CLASSIFICATION USED IN LAB The Animal Kingdom is subdivided into phyla (plural). Each phylum (singular) has certain characteristics they share in common. This lab will familiarize you with some of these characteristics. Each phylum is further subdivided into classes, for our purposes we have picked a few phyla for which you will learn the identifying characteristics of the associated classes (see below).
PHYLUM PORIFERA - sponges characteristics: a phylum of simple aquatic invertebrates with no symmetry (a few are radial) and only a cell level of organization.
PHYLUM CNIDARIA – jellyfish, sea anemones, coral, and freshwater Hydra characteristics: a phylum of aquatic invertebrates with radial symmetry. Cnidarians are character-ized by their simple pouch-like body (gastrovascular cavity), tentacles, and stinging cells.
PHYLUM FLATWORMS – Planaria and tapeworms characteristics: aquatic or terrestrial invertebrates with soft, flattened, worm-like bodies that possess a distinct head region and an incomplete digestive system (gastrovascular cavity).
PHYLUM MOLLUSKS – snails, slugs, clams, mussels, octopus, squid, and chambered nautilus. characteristics: a phylum of aquatic and terrestrial soft-bodied animals. All molluscs have a muscular foot and a mantle. The mantle is a special tissue that, in most mollusks, produces the calcareous shell. Each has a mouth and a complete digestive system.
CLASS GASTROPODS – snails, limpets, abalone, and slugs characteristics: freshwater, marine or terrestrial mollusks that possess a single shell, a distinct head with eyes, a mouth with a feeding structure called a radula. Gastropod means “stomach-foot” and all gastropods move on a large muscular foot on which they slowly move feeding on either algae or on other slow moving prey.
CLASS BIVALVES – clams, mussels, and oysters characteristics: aquatic mollusks that possess two shells and filter-feeding gills.
CLASS CEPHALOPODS – octopus, squid, and chambered nautilus characteristics: intelligent, marine mollusks. Cephalopod means “head-foot”. Their foot is modified into a cluster of tentacles. Cephalopods are fast moving, agile predators with complex eyes that feed on fast moving prey such as crabs or fish using beak-like jaws.
PHYLUM ANNELIDS – earthworms and leeches characteristics: invertebrates with bodies divided into segments, and a distinct head and tail. They have a complete digestive system and closed circulatory system. Gas exchange is through surface diffusion or gills in many aquatic species.
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PHYLUM ARTHROPODS – arachnids, crustaceans, centipedes, millipedes and insects. characteristics: a phylum of aquatic and terrestrial invertebrates that have jointed legs and a hardened exoskeleton of chitin.
CLASS ARACHNIDS – spiders, scorpions, and ticks characteristics: a class of arthropods that usually have bodies divided into two parts – a cephalothorax and abdomen. The cephalothorax has four pair (8) of walking legs.
CLASS CRUSTACEANS – crayfish, lobsters, barnacles, and crabs characteristics: a class of arthropods that usually have bodies divided into two parts – a cephalothorax and abdomen. The cephalothorax has five pair (10) of legs.
CLASS INSECTS – beetles, butterflies, flies, termites, grasshoppers, and dragonflies characteristics: a class of arthropods that possess a body with three parts (head, thorax and abdomen) and one pair of antennae. Many insects go through stages of development changing from a juvenile to an adult form (stages may include: adults, nymphs, pupae, or larvae).
PHYLUM CHORDATA – sharks, fishes, amphibians, reptiles, birds, and mammals characteristics: a phylum of aquatic and terrestrial animals that include all the vertebrate classes. All chordates have a notochord (stiffened tissue) and centralized nerve cord along the dorsal (back) part of the body; in vertebrates the nerve cord is covered with bone or cartilage.
CLASS CARTILAGINOUS JAWED FISHES – sharks and rays characteristics: vertebrates that have jaws and a skeleton composed entirely of cartilage.
CLASS BONY FISHES – ray-finned fishes (trout, salmon, & guppies), lungfish, and lobe-finned fish characteristics: vertebrates that have a skeleton composed of bone and paired fins.
CLASS AMPHIBIANS – frogs, toads, and salamanders characteristics: amphibians are a transitional form between water and land vertebrates. They often have aquatic larval stages in their life cycle and bodies with a moist, glandular skin. Amphibians are dependent on water (or moist places) to lay their eggs.
CLASS REPTILES – lizards, snakes, alligators, and turtles characteristics: vertebrates that have skin covered with scales; the number of legs vary from four, to two, to none. Most lay eggs that have a leathery covering that reduces loss of water.
CLASS BIRDS – gulls, sparrows, finches, penguins, ostriches, owls, and hawks characteristics: vertebrates with feathers, wings, and unusually efficient lungs. Birds lay eggs with calcium-hardened shells that protect the developing embryo.
CLASS MAMMALS – dogs, mice, bats, cats, deer, monkeys, humans, and whales characteristics: vertebrates that have hair or fur, maintain a constant body temperature, produce milk that is consumed by their young; most give live birth (a few lay eggs).
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ANIMAL DIVERSITY Phylum Porifera
Sponges have a simple body design consisting of a variety of cells specialized for particular functions, but without any assemblage of cells into specialized tissues. The three main types of cells are: pore cells, through which water flows into the sponge, collar cells (also known as choanocytes), which trap tiny food particles, and amoebocytes which perform many functions for the sponge, including secreting the skeletal material.
Sponges are believed to be among the earliest animals to evolve. Their collar cells are extremely similar to the cells of a type of colonial protozoan (Kingdom Protista). It is thought that sponges evolved from these protozoans that lived over 550 million years ago. In fact, molecular evidence suggests that all animals may have evolved from these protozoans.
Sponge structure and feeding
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Observation 1 – Sponges continued 1. What is the sponge’s habitat?
2. What level of organization do sponges have?
3. What type of symmetry do sponges exhibit?
4. What type of digestive system do sponges possess: none, complete or incomplete?
Where does digestion occur in a sponge?
5. What type of gas exchange surface do sponges have?
6. What type of circulatory system do sponges have?
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Phylum Cnidaria Cnidarians are also very simple animals that arose early in evolutionary history. However, cnidarians show a higher level of complexity than the sponges. The cnidarians are the first animals to evolve tissues, collections of similar cells working together for a common function. These animals have a simple body design with tissues that are two cell layers thick. They have one internal cavity (gastrovascular cavity) with a mouth and tentacles around the mouth. There are two body designs: polyp and medusa. The polyp is sessile and the medusa is a free-floating body type. Polyp Medusa
The tentacles are armed with stinging cells. Each stinging cell has a coiled thread or “stinger” with barbs or spines. When it receives a signal, the stinger shoots out, harpooning the prey with poison barbs.
2. How are stinging cells used by these animals? Sea Anemone Jellyfish Hydra
A skeleton without hard parts – Hydrostatic skeleton Most animal groups do not have a hard skeleton, but they still need something for their muscles to pull on. One solution is to use a fluid-filled cavity to work against. Sea anemones (Phylum Cnidaria) use their central gastrovascular cavity as a hydrostatic skeleton. They have two groups of opposing muscles, circular and longitudinal. The circular muscles form a rings around the “stalk” of the animal, the longitudinal ones run up and down.
Anemone with tentacles withdrawn Anemone extended
1. Which muscles do sea anemones contract to extend its body, the rings of circular muscles
around the stalk or the longitudinal (up and down) muscles?
2. Which muscles do they contract to pull its tentacles in, the rings of circular muscles around the stalk or the longitudinal (up and down) muscles?
3. What are the muscles of a sea anemone contracting against?
Hydra (Phylum Cnidaria) Examine the prepared Hydra slide under the microscope.
1. What level of organization do cnidarians have?
2. What type of symmetry is found among the cnidarians?
3. What type of digestive system do Hydra and all cnidarians possess: none, complete or incomplete?
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Corals (Phylum Cnidaria) Corals are typically made up of colonies of cnidarian polyps. The polyps secrete calcium carbonate skeletons around themselves. These skeletons form the structure of coral reefs, one of the most diverse ecosystems on the planet.
A. Examine the coral skeletons at the side bench.
B. Identify the holes where a coral polyp was once living.
1. After coral dies, what remains?
2. How is the skeleton created?
3. Label the drawing of coral, identifying the animals and the skeleton.
Many corals have a symbiotic relationship with photosynthetic algae called zooxanthelle. Although the coral may gather some food using their tentacles, they depend on their algal partners to provide them with photosynthetic nutrients (sugars). If a coral loses its zooxanthelle, it will not survive.
4. Although coral is an animal, it only lives in relatively shallow water where there is light. Why
is this?
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Phylum Flatworms Flatworms have a distinctive shape. They are flattened and have sensory organs clustered in their head. A muscular pharynx on the lower side of the body opens into a digestive system with only one-opening (gastrovascular cavity). Flatworms can be either free-living or parasitic. Unlike cnidarians and sponges, flatworms and all other animals have organs and organ systems. However, flatworms are relatively simple animals and share other traits in common with cnidarians. Planaria (or Degusia) prepared slide
A. Label the pharynx and eye spots on the illustration and attempt to locate them on your specimen. 1. What level of organization do flatworms have?
2. What type of symmetry is found among the flatworms?
3. What type of digestive system do flatworms possess: complete or incomplete? What structure does it use to feed? Does flatworm digestion occur primarily within cells (intracellular) or outside cells (extracellular)?
4. What type of gas exchange surface do flatworms have? How does oxygen get from the flatworm’s environment to the body cells? How does the shape of a flatworm make the process of gas exchange more efficient?
5. Flatworms live in freshwater ponds and streams and searches out decaying material to eat.
Where are the sensory organs of the flatworm located? What makes this body plan well-suited to this method of getting food?
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Phylum Mollusks The phylum Mollusca (Mollusks) is extremely diverse. However, most members share these features in common: a muscular foot, usually used for movement, a calcium carbonate shell, and a mantle (an outgrowth of their body) that secretes the shell or covers the body when a shell is absent. Most mollusks also have a radula, a rasp-like structure unique to this phylum that is used to scrape food off of surfaces. Most mollusks belong to one of three classes, Gastropods, Bivalves, and Cephalopods. Gastropod means "belly foot" and this class of mollusks have a large foot on the bottom of the organism for movement. These include snails (aquatic and terrestrial), slugs, abalone, and limpets. Almost all feed with their radula. The slug is unique in this group in not having a shell at all as an adult. Bivalves are a class of mollusks with shells divided into two halves that are hinged together; examples include clams, mussels, scallops, and oysters. Clams use their foot to burrow and dig, while mussels use it to help apply special threads that hold them to a rock. Most are filter feeders and use their gills to help filter food as well as gas exchange. They do not have a radula. The cephalopods are a class of fast-moving, agile mollusks with large brains and sophisticated sensory organs; cephalopods include squid, octopus, and the chambered nautilus. There is great diversity in the cephalopods with regards to the shell. The nautilus has an elaborate, external shell, squids have a reduced, internal shell called a pen, and the octopuses lack a shell all together. They all possess a mantle. Cephalopods lack a radula, instead they possess a sharp beak for crushing or ripping up their prey.
Class Gastropods: Snails and slugs
1. What level of organization do snails, and all mollusks, have?
2. What type of symmetry do mollusks exhibit?
3. What type of digestive system do mollusks possess: complete or incomplete? What are advantages of a complete digestive system compared to an incomplete digestive system?
4. What type of gas exchange surface do terrestrial snails have? What about marine mollusks?
The circulatory system of mollusks varies by class. What type of system is found in each class? Gastropod: Bivalve: Cephalopod: What is the difference between an open and closed circulatory system?
Why does the circulatory system differ among the classes of mollusks? (Hint: what are the differences in lifestyle for each type?) Mussels and clams are mollusks in the class bivalve. Based on their circulatory system, what type of lifestyle do they have? How do they feed?
8. What are two characteristics all of these animals have in common which places them in the
phylum Mollusca? (Hint: remember, bivalves don’t have a radula)
a.
b.
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Phylum Annelids Annelids are segmented animals that have a hydroskeleton. They have a complete digestive system with a mouth at one end and an anus at the other. Along the length of their bodies the digestive system is specialized with various functions (like an assembly line). Annelids are found in both terrestrial and aquatic habitats. This phylum includes earthworms, leeches, and marine polychaete worms.
Earthworm Model
1. What level of organization do annelids have?
2. What type of symmetry do annelids exhibit?
3. What type of digestive system do Annelids possess: complete or incomplete?
4. What type of gas exchange surface do earthworms have?
5. What type of circulatory system do earthworms have?
6. Earthworms use iron in their blood to transport oxygen. However, marine segmented worms (polycheates) use another metal, what is it?
7. What is the important ecological role of earthworms in terrestrial environments?
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Phylum Arthropods Arthropods are one of the largest and most successful phyla. Arthropods include insects, spiders, crustaceans (shrimp, lobsters, and barnacles) and are found in nearly every habitat on earth – terrestrial and aquatic. All arthropods have a segmented body with an exoskeleton made of chitin. Their appendages are jointed; some are legs and can be many (millipedes) or as few as six (insects).
Arthropods – Crayfish A. Observe preserved crayfish.
B. Notice the two parts to its body and the joints in the legs.
1. How many legs does the crayfish have? Label the crayfish appendages indicating whether they are used for swimming, walking, defense, or other sensory functions.
2. What is the crayfish’s natural habitat?
3. What level of organization do arthropods have?
4. What type of symmetry do arthropods exhibit?
5. What type of circulatory system do arthropods possess?
6. What type of gas exchange surface do aquatic arthropods have?
7. Insects also have an open circulatory system, but they can be very fast moving and expend a lot of energy. What gas exchange system allows this?
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Arthropod Examples: Arrange By Class in the table on the following page A. Black widow spider B. House fly
C. Tick D. Beetle
E. Scorpion F. Dragonfly
G. Marine Crab H. Butterfly
Observation 10 – The Diversity of Arthropods On the side bench are various Arthropods from different habitats, all with an exoskeleton, jointed appendages and a segmented body.
Give the common name of each arthropod indicated on the previous page and give its class below (see descriptions on page 8-3). List characteristics that distinguish each class: how many walking appendages (legs) does the organism have? What other types of appendages does each organism have (defense, feeding, swimming, sensory, etc.)?
Common Name Class Characteristics a. Black widow spider b. House fly c. Tick d. Beetle e. Scorpion f. Dragonfly g. Marine Crab h. Butterfly
1. Which of the above arthropods are aquatic? Terrestrial?
2. Which arthropod class is most successful on earth?
3. How are aquatic arthropods different from terrestrial arthropods? In other words, what kinds of adaptations (in terms of appendages or structures) do terrestrial arthropods have that are different from aquatic arthropods?
4. Some arthropods change from aquatic to terrestrial during their lifetimes. Give one example and some changes (include gas exchange structures) that occur that adapt them to each environment.
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Phylum Chordates Despite the fact that chordates account for less than 4% of all animal species, they are the most familiar group of animals for most people. All have a nerve cord that runs down their back. The largest group of chordates (the vertebrates) also has a segmented backbone that protects the nerve cord, a skull, and hinged jaws. There are several different classes of vertebrates:
Cartilaginous Fish Their skeleton is made of cartilage, not bone.
Bony Fish Their skeleton is reinforced by calcium salts (bone).
Amphibians Live part of their life on land and part in water. Their eggs, larvae and juveniles are aquatic, while the adults are usually mostly terrestrial. During their lifetime they use a mixture of gills, lungs, and gas exchange through their skin.
Reptiles All have scales and lungs; most lay eggs with leathery covers.
Birds Maintain a constant body temperature, have feathers and wings, and lay eggs with hard shells.
Mammals Maintain a constant body temperature, have hair (or fur), give live birth, and have mammary glands to produce milk for the young.
The Diversity of Chordates.
1. What is a vertebrate?
2. What level of organization do vertebrates have?
3. What type of symmetry do vertebrates exhibit?
4. What type of digestive system do vertebrates possess: complete or incomplete?
5. Compare the classes of vertebrates. What type of gas exchange surfaces are found in each class (some use more than 1)?
6. What type of circulatory system do vertebrates have?
8. What is (are) the unique or distinguishing characteristic(s) of the phylum Chordata?
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Chordate Vertebrates: The Mammals Mammals are categorized by their dentition (tooth patterns). There are 3 different types of teeth: incisors, canines, and molars. Much can be learned about an animal by observing their type of teeth, and how the teeth are arranged in the jaw. Teeth tell us whether mammals are carnivores, herbivores, omnivores, etc. Carnivores have reduced molar with sheering edges, but well-developed canine teeth for ripping flesh. Grazing herbivores use their front incisors for clipping off vegetation, and well-developed molars for grinding their food. Gnawing herbivores have specialized incisors used for gnawing their food; these incisors grow throughout their lives. Omnivores have teeth that are less specialized for a specific task.
A. Observe the skulls and jaws placed on the tables at the side of the lab. Notice the number, size, shape, and arrangement of the teeth.
1. For each skull decide if the animal is an herbivore, omnivore, or carnivore.
a. deer What well-developed set of teeth lead to your conclusion?
Which set of teeth are less well developed?
b. beaver What well-developed set of teeth lead to your conclusion?
Which set of teeth are less well developed?
c. dog What well-developed sets of teeth lead to your conclusion?
d. cat What well-developed sets of teeth lead to your conclusion?
e. monkey Describe the teeth and how they led you to your conclusion.
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Animal Phyla Characteristics Summary
Fill in the following chart with characteristics of each phylum. This is a good way to organize your thoughts in preparation for the lab exam. Phylum Examples Habitat Level of
