Animal Study Guide PDF

Animal Study Guide Terms: Animal; a multicellular eukaryotic heterotroph whose cells lack a cell wall. **Two Divisions in the Animalia Kingdom:** Vertebrates (3% of all animals); animals with a backbone. Invertebrates (97% of all animals); animals without a backbone. **The Seven Phylum:** Por...

Animal Study Guide Terms: Animal; a multicellular eukaryotic heterotroph whose cells lack a cell wall. **Two Divisions in the Animalia Kingdom:** Vertebrates (3% of all animals); animals with a backbone. Invertebrates (97% of all animals); animals without a backbone. **The Seven Phylum:** Porifera (pore bearing); sponges Cnidarian (stinging nettle); jellyfishes, sea anemone, sea pens, coral, hydra. Platyhelminthes; flatworms Nematoda; roundworms Mollusca; clams, oysters, snails. Annelids; segmented worms (e.g. earthworms) Arthropods; lodestars. **Cell Specialization**; the bodies of animals contain many specialized cells. Each one has a shape, cell structure, and chemical composition that make it uniquely suited to perform a particular function within a multicellular organism. Groups of specialized cells carry out tasks for the organism (process known as division of labor). If there are no efficient systems to carry out essential functions such as feeding, respiration, and elimination of waste cells would be starved of food and oxygen and would be smothered in carbon dioxide and other waste due to them having their surface exposed to the environment. Without specialization, organisms would lack the ability to perform the diverse and complex functions needed for survival. **General Characteristics;** Heterotrophic and usually obtain food through ingestion followed by digestion. Can move by muscle fibers. Multicellular with specialized cells. Typically, a dominant adult stage in life cycle. Usually has sexual reproduction and produces an embryo that undergoes developmental stages. **Evolution;** More than 30 phyla are believed to have evolved from a protistan ancestor. Difficult to trace because many animals are soft-bodied and do not fossilize. **Animal Survival:** **Feeding;** Herbivores eat plants (roots, stems, leaves, flowers, fruits, nutrient-rich fluids in plant vascular tissues.) Carnivores eat meat (other animals; blood, fat, bone marrow, muscle). Omnivores eat both plant and meat. Parasites feed either inside their host or attached to the host's outside surface. Filter Feeders (aquatic animals) filter organisms out of water (tiny floating plants and animals). Detritus feeders feed on decaying plant and animal materials (similar to saprophytes; hagfish/crab/lobsters). **Respire**; exchange oxygen and carbon dioxide with the environment. Diffusion through cell membrane/skin/lungs/gills/spiracles (a hole inside insects\' body). **Internal Transport;** movement of gases, nutrients, and wastes products around the organism. Many multicellular organisms have evolved cytoplasm/circulatory system in which the heart moves blood through different blood vessels. *Instead of a circulatory system, sponges and mesoglea (e.g. jellyfish and hydra) have semi-fluid matrix. Some aquatic animals like worms can function without an internal transport system.* **Excretion**; diffusion of nitrogenous wastes (e.g. ammonia and urea), which are toxic to the body, through cell membranes/tissues (e.g. some aquatic animals)/flame cells/ excretory pores/ excretory system (nephrons/kidneys/bladder). **Response**; ears and eyes (sense organs) respond to stimuli in the environment (e.g. chemical, light, sounds, temperature receptors). Development of nerve cells and tissue which hook together to create the nervous system (brain/spinal cord processed the information and regulates how to respond). **Movement;** Sessile; spend their adult life attached to something (e.g. barnacles, sponges, coral, sea anemone). Motile can move around (free living) by using muscles to generate force (e.g. jellyfish, birds, dogs, humans). Sedentary can move but remains in one spot often (e.g. sea urchins, sea star). **Reproduce**; may have sexual or sexual stage. The organism is a diploid (two sets of chromosomes); only sex cells or gametes (egg and sperm) are haploid (one set of chromosomes). Most organisms have direct development where a baby develops into a adult without a change in it's life form. Other organisms (e.g. Insects) lay eggs that hatch into larva which later undergoes metamorphosis in which they change shape into a different adult form. **Levels of Organization in Cells;** Cells; smallest unit of life. Tissues; a group of the same type of cell (e.g. muscles, epithelial; covers digestive tract, nervous; brain/spinal cord, connective; ligaments, collagen, tendon, carting). Organ; different types of tissue grouped together (e.g. skin, head, etc). Organ system; organs gathered together. **Symmetry;** Asymmetrical has no particular symmetry (e.g amoeba) Radial is two identical halves no matter how the animal is divided longitudinally. Body parts repeat around an imaginary line drawn through the center of their body (e.g. simple animals; jellyfish). Bilateral are definite right and left halves. Body parts are repeated on either side of an imaginary line drawn down the middle of their body. ***The anterior is the front end, and the posterior is the back end. The dorsal is the upper side and the ventral is the lower side*** (e.g. complicated animals; planaria). **Cephalization**; gathering of sense organs and nerve cells at the anterior end of the animal (head). Nerve cells in the head gather into clusters that process the information gathered by the nervous system and control the responses to the stimuli. Ganglia (clusters of nerve cells) gather together to form brains. (e.g worms) **Body Cavity:** Coelom; a body cavity completely lined with mesodermal tissue; mesodermal tissue forms mesentery which holds internal organs in place. Pseudocoelom; a body cavity incompletely lined with mesodermal tissue. Acoelomate; no body cavity; interior space filled with mesoderm tissue. **Segmentation** (repetition of body parts along the length of the body): Non-segmented; mollusks (e.g. clams) echinoderms (e.g. starfish). Segmented; annelids (e.g. earthworms), arthropods (e.g. lobsters), chordates (mammals); each segment is specialized for a particular function. **Trends Observed in The Evolution of Animals:** **Organization of cells, symmetry, development of anterior/posterior/dorsal/ventral, cephalization.** **Cephalization;** gathering of sense organs and nerve cells at the anterior end of animal. **Phylum Porifera (sponges):** Kingdom Animalia Phylum Porifera ("pore-bearing") Among the most ancient species alive today (beginning of the Cambrian Species 580 million years ago). Approx. 5000 species **Habitat;** water from the surface to the depths (fresh water; 150 species, poles or topic waters; Great Barrier Reef). **Ecological Role**; provides shelter and/or food to other organisms. Form symbiotic relationships with bacteria, blue-green bacteria, and plant like protists. Boring sponges release chemicals that bore holes into the skeletons of sponges and other shelled organisms which helps breakdown the skeletons and recycle calcium to be used by other organisms. **Medical Role;** can produce chemicals to repel other animals. These chemicals are shown to be useful in treating leukemia, herpes, viral infections and arthritis. Used sponges for bathing, body amour (Greeks), paint brushes (Romans). **Structure**; asymmetrical or radial symmetry. Cellular level of organization with special cells. Live independently or in a colony. Colors range from red, orange, yellow, green, brown, purple, black and white and can regenerate loss body parts. Their internal structure is composed of spicules; composed of calcium carbonate (chalk from sponges) silica (glass sponges) or spongin (type of protein). Egg/sperm -producing structures. Pores; openings in the body wall found in between the epidermal cells. Collar cells; cells that have flagella and trap food particles. Osculum; large hole where water leaves the sponges. Amoebocytes; a special kind of cell that builds spicules. Also is used for digestion. Central Cavity; the area enclosed by the body wall of the sponge. Spicule; one of the many structures that form the skeleton of the sponge. Pore Cell; specialized cell through which water enters sponge. Epidermal Cell; cell on the outer surface of the sponge. Semi-Fluid Matrix; the middle layer of the sponge. **Ingestion**; feed on zooplankton, phytoplankton (green algae), detritus (decaying) particles and bacteria. The beating flagellum of collar cells produces water currents, while the collar cells filter (feed) particles out of the water that passes through the sponge. Collar cells then phagocytize (engulf) the food particles into food vacuoles. *\*a 10cm sponge can filter up to 10 liters of water a day\** **Digestion**; collar cells digest food in food vacuoles (organelles that store food temporarily) or pass them to amoebocytes for digestion. Amoebocytes digest food intracellularly after phagocytizing the food particles. **Respiration**; dissolved oxygen diffuses (molecule move from high to low concertation) from the water into sponge and carbon dioxide diffuse out of the sponge into water. **Internal Transport**; water current brings nutrients in and waste out of sponge and the semi-Fluid matrix transports such nutrients and waste through the sponge. **Elimination;** wastes are eliminated through the osculum. **Excretion**; nitrogenous waste is diffused out of the sponge, carried out of the osculum and into the water. **Locomotion**; sessile (adult); motile (swimming larvae). **Response**; none; no nerve cells. **Reproduction**; sponges are Hermaphrodites meaning each sponge possesses male and female reproductive structures. Sponges can reproduce asexually by budding or by producing gemmules (if it's a freshwater sponge). Gemmules resist freezing (an unfavorable condition) similar to that of an endospore (bacteria) or spore (fungi). Sponges can also reproduce sexually when their sperm is released into the water and travels by the water current to the eggs in the sponge. The sperm enters through the pore and is picked up by an amoebocyte which carries the sperm to eggs for fertilization. The fertilized egg develops into a zygote, then into a swimming larva which then travels by water current to a new place and attached to it. There it will form a new sessile sponge. **Phylum Cnidarian:** **Habitat; m**ostly oceans, some in freshwater lakes and rivers, poles to tropics, at the surface deep in the water column. **Ecology; f**ood source and provides shelter (e.g. coral, sea anemone \[clownfish\], sea pens). Some form symbiotic relationships with dinoflagellates and green algae (e.g. jellyfish lake in Palau). **General Characteristics\'; c**nidarians have radial symmetry. Their body is organized into true tissues, and they have stinging structures called nematocysts on their tentacles. The polyp (tentacles up) and medusa (tenacles down) stages are stages in their life cycle, one being the dominant stage. Two cell layers; epidermis (outer layer) and gastrodermis (inner layer), and between both is the mesoglea (jelly-like substance containing collagen fibers). Have a one-way digestive tract, mouth and anus. **Four Classes;** Anthozoa; 2700 species, alternate between a polyp and medusa stage. E.g. *True corals (calcium carbonate skeleton), anemones, sea pens, Portuguese man-o-war.* Cubozoa; 15 species, dominant medusa stage, sting can be lethal, amazing jellyfish with complex and potent toxins (neuro muscular). E.g. *Box jellyfish.* Hydrozoa; the most diverse group, Hydra's have dominant stage polyp stage, most have dominant medusa stage. *E.g. Hydroids, fire corals.* Scyphozoa; over 200 species, free swimming dominant medusa stage. *E.g. True jellyfish.* **Hydra Notes:** Kingdom Animalia Phylum Cnidaria Class Hydrozoa **Habitat**; fresh water and marine. **Structure;** dominant polyp stage. Gastroderm; inner layer Epidermis; outer layer Mesoglea; a jelly-like substance containing collagen fibers (wandering amoebocytes) that acts as the thick middle layer. Gastrovascular Cavity; is inside the gastrodermis layer, is an organ for digestion. Mouth; opening to the gastrovascular cavity, entrance for food and exit for waste. Tentacles; flexible and mobile organ. Nematocysts; stinging cells that eject a barbed or poison hook when triggered by a chemical or by touch, used as a preying technique. **Ingestion;** tenacles pull prey into mouth. **Digestion;** Extracellular (outside the cell) digestive enzymes are released into the gastrovascular cavity to digest food. Intracellular (inside the cell) phagocytosis (cell eating) of food particles and then digestion within lysosome (vacuole enzymes). **Elimination**; mouth-anus **Excretion**; diffusion through epidermis. **Internal Transport**; water current through gastrovascular cavity and mesoglea. **Respiration**; diffusion of oxygen and carbon dioxide through epidermis or gastrodermis. **Locomotion**; circular and longitudinal muscle fibers in the mesoglea layer contracts. Usually sessile but can glide, slide, creep, or tenacle walk, or make air bubbles and float. **Response**; nematocysts eject a barbed or poison hook when triggered by a chemical or by touch, used as a preying technique. Nerve cells are located below the epidermis near the mesoglea and form a nerve net, which communicates with sensory cells through the body using nerve impulses (nerve net transmits multi-directional nerve impulses). **Reproduction**; asexual reproduction is done by budding, and sexual reproduction is done when sperm and eggs are released into the water. Internal fertilization occurs when the sperm is taken in through the mouth-anus and fertilizes the egg in the gastrovascular cavity. Fertilization can occur in the water too (external fertilization). **Jellyfish Notes;** Kingdom Animalia Phylum Cnidaria Class Scyphozoa **Habitat**; all marine **Structure;** dominant medusa stage. Gastrodermis; inner layer. Epidermis; outer layer. Mesoglea; a jelly-like substance containing collagen fibers (wandering amoebocytes) that acts as the thin middle layer. Gastrovascular Cavity; is inside the gastrodermis layer, is an organ for digestion. Mouth; opening to the gastrovascular cavity, entrance for food and exit for waste. Tentacles; flexible and mobile organ. Nematocysts; stinging cells that eject a barbed or poison hook when triggered by a chemical or by touch, used as a preying technique. **Praying Technique**; float on top of prey and covers it before stinging it with its tentacles. **Ingestion;** tenacles pull prey into mouth. **Digestion;** Extracellular (outside the cell) digestive enzymes are released into the gastrovascular cavity to digest food. Intracellular (inside the cell) phagocytosis (cell eating) of food particles and then digestion within lysosome (vacuole enzymes). **Elimination**; mouth-anus **Excretion**; diffusion through epidermis. **Internal Transport**; water current through gastrovascular cavity and mesoglea. **Respiration**; diffusion of oxygen and carbon dioxide through epidermis or gastrodermis. **Locomotion**; circular and longitudinal muscle fibers in the mesoglea layer contracts. It also uses jet propulsion as water is squeezed out of the gastrovascular cavity through the mouth and anus. **Response**; eyespot or ocelli (detect light) that the outer ring of the bell-shaped medusa. Statocysts are cells used for orientation. Nematocysts eject a barbed or poison hook when triggered by a chemical or by touch. Nerve cells are located below the epidermis near the mesoglea and form a nerve net, which communicates with sensory cells through the body using nerve impulses (nerve net transmits multi-directional nerve impulses) **Reproduction;** asexual reproduction is done by budding, and sexual reproduction is done when sperm and eggs are released into the water. Internal fertilization occurs when the sperm is taken in through the mouth-anus and fertilizes the egg in the gastrovascular cavity. Fertilization can occur in the water too (external fertilization). **Life Cycle of a Jellyfish;** Polyp Stage; tentacles up, structure is flower-like, and locomotion is sessile (stays attached to something their adult whole life). They are at the asexual stage in the life cycle as they reproduce by budding or fission to form new polyps (or can developed into medusas through strobilation). *E.g. Hydra.* Medusa Stage; tentacles down, structure is bell-like, and locomotion is motile (can move by suing their muscles/tissues). They are at the sexual stage in the life cycle, as they release sperm and eggs into the water to reproduce sexually. *E.g. Adult form of jellyfish.* *Both of radial symmetry and some of the same structures including a gastrovascular cavity and tentacles (some placement near/around their mouths). They both possess a nerve net and a one-way digestive tract. They are also from the same life cycle.* **Unsegmented Worms:** **Flatworms Notes:** **Kingdom Animalia** **Phylum Platyhelminthes** **Planaria Structure (Class Turbellaria);** Pharynx; opening to the gastrovascular cavity. An entrance for food. Gastrovascular Cavity; forms the intestine that has many branches. Mouth; opening at the tip of the pharynx. Undigested waste materials are eliminated through the mouth. Anterior; the head where the brain is located. Posterior; the back end. Flame Cells; are used to get rid of excess water (and waste). These flame cells join and empty the water through pores in the animal\'s skin. Eyespots/ocelli; detect lights. These cells are so sensitive to chemicals (in food) that are scattered all over the body. Cilia; located on the epidermis cells and helps the free-living worm move. Dorsal; upper side of an organism that has bilateral symmetry. Ventral; lower side of an organism that has bilateral symmetry. **Tapeworm Structure (Class Cestoda);** Scolex; their head. Hooks; rings of hooks are located on the scolex and are used to attach to their hosts' intestinal wall. Suckers; located on the scolex and is used to attach to their host's intestinal wall. Proglottids; make up the body of the tapeworm. The younger proglottids are the closest to the anterior end, and the mature proglottids are towards the posterior end. They contain both gender reproductive organs. *\*Fertilized tapeworm eggs are released when mature proglottids break off the posterior and burst open. \** **Roundworms Notes;** Kingdom Animalia Phylum Nematoda **Ascaris (Parasitic) Structure;** Mouth; an entrance for food. Ganglia; a group of nerve cells. Make up the nervous system (no brain). Nerves; transmit sensory information and control movement. Intestine; used for digestion. Reproductive organs; undergo reproduction. Most reproduce sexually, most have separate sexes and others are hermaphroditic. Anus; food that cannot be digested leaves through the anus. **Earthworm (Annelid/Class Oligochaetes) Structure;** Prostomium: The front-most segment of the body, often covering the mouth, and it helps the worm sense its environment. It's located just in front of the mouth. Mouth: the opening through which the worm takes in food. Located just behind the prostomium. Setae: small bristle-like structures that project from each segment of the worm's body. They help in locomotion by anchoring the worm to the soil and providing traction. Somite; a segment of the worm\'s body. Each somite contains parts of the digestive, circulatory, and nervous systems. An earthworm typically has over 100 somite\'s. Seminal Receptacles; organs in the female reproductive system that store sperm after mating. They are located in segments 9 and 10 in earthworms. Oviduct; tubes through which eggs pass from the ovaries to the exterior. In females, eggs are deposited through the oviducts. Sperm Ducts; tubes through which sperm are transported from the testes to the exterior or to the seminal receptacles during reproduction. Clitellum; a thick, saddle-like band of tissue around certain segments (usually segments 32-37) of the worm. It plays a role in reproduction by secreting mucus that helps in the formation of a cocoon for eggs. Pharynx; the muscular part of the digestive system that sucks in food. Located just after the mouth, it aids in ingesting food. Esophagus; a short tube that connects the pharynx to the crop, moving ingested food further along the digestive tract. Gizzard; a muscular organ that grinds food into smaller particles. It follows the crop in the digestive system. Intestine; the long, coiled part of the digestive system where digestion and absorption of nutrients take place. Anus; the opening through which undigested food (waste) is excreted from the body, located at the posterior end. Aortic Arches (ring vessels); a set of five pairs of blood vessels that function as hearts. They help pump blood through the circulatory system. Dorsal Blood Vessel; a blood vessel located on the upper side of the worm\'s body. It carries blood from the posterior (back) part of the body toward the anterior (front). Ventral Blood Vessel; located on the lower side of the body, this vessel carries blood from the anterior to the posterior part of the body. Ganglia; a cluster of nerve cells that function as a local \"brain\" or nerve center for each segment of the worm. Brain; a small mass of nerve tissue located at the anterior end of the worm, above the pharynx. It controls the nervous system and coordinates responses to stimuli. **Infection by a Tapeworm;** Several suckers and a ring of hooks attach to the intestinal walls of humans and other animals. Inside the intestine, there is food that has already been digested by the host, ready for the tapeworm. The worms absorb this food through their body walls. Tapeworms almost never kill their host, but they do use up a lot of food which is why hosts may lose weight and become weak. The tapeworm can enter your body by drinking or eating food and water contaminated with tapeworm eggs. **How Unsegmented Worms Fit into the World;** Hook worm- infect intestines ex. Ascaris Trichinella- causes trichinosis. Rats and pigs are common hosts for trichinella Filarial worms- are threadlike. Found primarily in regions of Asia, live in blood or lymph vessels of their hosts. Elephantiasis is a condition in which the affected part of the body swells enormously Eye worms are closely related to filarial worms and can live in humans and baboons, the worms burrow in and through the tissues of the skin and can move across the surface of the eye. African river blindness is caused by a roundworm that enters through the bite of an infected black fly. Can live in there for 12 years. Inching and blindness are symptoms of infection. **Earthworms Importance;** They break down organic matter (like dead leaves) into nutrients that plants can use. Their burrowing creates tunnels, allowing air and water to reach plant roots. They speed up the breakdown of organic material, recycling nutrients into the soil. Their tunnels help water move through the soil, preventing waterlogging. They support other organisms by improving soil quality and fertility. **Compare and Contrast:** **Compare;** All three have bilateral symmetry and are triploblastic. Each has a distinct body structure adapted to its environment. **Contrast;** Planarian: Acoelomate. Ascaris: Pseudocoelomate. Earthworm: Coelomate. Digestive System: Planarian: Incomplete. Ascaris & Earthworm: Complete. Body Shape: Planarian: Flat and thin. Ascaris: Cylindrical but unsegmented. Earthworm: Cylindrical and segmented. **Adaptation:** Free-Living Worms (e.g., Planarians): Flat bodies for gas exchange. Cilia for movement. Eyespots to detect light. Burrowing Worms (e.g., Earthworms): Segmented bodies and bristles for movement in soil. Moist skin for gas exchange. Digestive structures (crop, gizzard) for breaking down organic matter. Parasitic Worms (e.g., Ascaris, Tapeworms): Protective outer layer against host defenses. Hooks or suckers for attachment. High reproductive capacity and simplified systems (e.g., direct nutrient absorption). **Platyhelminthes (Flatworms):** Bilaterally symmetrical, cephalization, and have simple organ systems. **Flatworms:** Free-living species: Digest food via a branched gastrovascular cavity; rely on diffusion for gas exchange and waste removal. **Nervous system:** Simple brain, paired nerve cords, light-sensitive eyespots (ocelli). **Reproduction:** Sexual (hermaphrodites) and asexual (fission, regeneration). **Parasitic Species**: Simple/no digestive tracts; attach to hosts with hooks or suckers. Examples include tapeworms and blood flukes. **Phylum Nematoda (Roundworms):** Long, tube-like digestive system (mouth and anus). Found in diverse environments. **Roundworms:** **Digestive system**: Simple, tube-like (mouth to anus). **Nervous system**: Ganglia and chemical-sensing organs. **Reproduction**: Sexual (separate sexes, some hermaphrodites). Parasites like Ascaris complete life cycles in hosts. **Environmental impact:** Some roundworms harm crops; others decompose organic matter. **Segmented Worms (Annelids):** Segmented body with septa (internal walls). Classes include Polychaeta (marine worms), Oligochaeta (earthworms), and Hirudinea (leeches). **Feeding**: Varied diet (detritus, algae, blood). Use jaws or mucus to capture food. **Respiration**: Gas exchange through skin or gills. **Circulatory System**: Closed, with dorsal/ventral vessels and \"hearts\" (aortic arches). **Excretion**: Waste removed via nephridia. **Nervous System**: Brain, ventral nerve cord, and sensory cells for light, chemicals, and vibrations. **Movement**: Longitudinal and circular muscles facilitate burrowing or swimming. **Reproduction:** Sexual: Internal or external fertilization; some hermaphroditic species exchange sperm and form protective cocoons. Asexual: Budding. **Ecological Importance:** Aerate soil, recycle nutrients, and serve as food for other animals. Leeches have medical applications (e.g., preventing blood clots).