UNIT X KINGDOM ANIMALIA Big Campbell Ch 32

UNIT X – KINGDOM ANIMALIA Big Campbell – Ch 32 - 34, 40, 44, 46, 53 - 55 Baby Campbell – Ch 18, 20, 25, 27, 36, 37

I. ORIGINS OF KINGDOM ANIMALIA

I. ORIGINS OF KINGDOM ANIMALIA, cont

II. INTRODUCTION TO KINGDOM ANIMALIA • • Ø • • Bodies held together with structural proteins Ø Collagen • Regulatory genes Ø Hox genes • Reproduce sexually Ø

II. INTRODUCTION TO KINGDOM ANIMALIA, cont Embryonic Development In Animals

III. CLASSIFICATION OF ANIMALS • Based on. . . A. Presence or absence of true tissues B. Symmetry C. Development of germ layers D. Presence of body cavity E. Embryonic development A. Tissues • • Metazoa (Parazoa) – organisms without true tissues Eumetazoa – organisms with true tissues

III. CLASSIFICATION OF ANIMALS, cont B. Symmetry • Asymmetry • Radial • Bilateral – cephalization

III. CLASSIFICATION OF ANIMALS, cont C. Development of Germ Layers • Form various tissues & organs Ø Ectoderm Ø Mesoderm Ø Endoderm • Diploblastic Organisms Ø 2 layers Ø No mesoderm • Most animals are triploblastic

III. CLASSIFICATION OF ANIMALS, cont D. Presence of Body Cavity • Only applies to triploblasts • Acoelomates Ø No body cavity Ø Solid body Ø • Pseudocoelomates Ø “False” body cavity Ø Not lined with mesoderm Ø • Coelomates Ø True body cavity Ø All other animals

III. CLASSIFICATION OF ANIMALS, cont E. Embryonic Development • Applies to organisms with bilateral symmetry, primarily coelomates • Protostomes Ø Spiral cleavage Ø Schizocoelous Ø Opening formed during gastrulation (blastopore) becomes mouth Ø Mollusks, annelids, arthropods • Deuterostomes Ø Radial cleavage Ø Enterocoelous

III. CLASSIFICATION OF ANIMALS, cont

IV. INVERTEBRATES • Make up 95% of all animals • Most scientists agree on approximately 35 animal phyla • 34 of these are made up of invertebrates

V. PHYLUM CHORDATA

V. PHYLUM CHORDATA, cont

V. PHYLUM CHORDATA, cont • Four characteristics common to all chordate embryos – Notochord – Flexible rod located between digestive tract & nerve cord – Dorsal Hollow Nerve Cord – Eventually develops into brain and spinal cord – Pharyngeal Slits – Present in developmental stages; may not be found in adult stage – Post-anal Tail • Divided into 3 sub-phyla: – Urochordata – Cephalochordata

V. PHYLUM CHORDATA, cont Invertebrate Chordates • Lack a true backbone • Suspension feeders • Closest vertebrate relatives; appear 50 million years prior to vertebrates • Subphylum Urochordata – Tunicates, sea squirts – Sessile as adults • Subphylum Cephalochordata

VI. PHYLUM CHORDATA - Subphylum Vertebrata • Notochord secretes proteins that make up somites – differentiate into vertebrae, ribs, skeletal muscles of trunk • Pronounced cephalization • Closed circulatory system with chambered heart

VI. PHYLUM CHORDATA - Subphylum Vertebrata Class Agnatha • Jawless vertebrates • Most primitive, living vertebrates • Lack paired appendages • Cartilaginous skeleton • Notochord present throughout life • Rasping mouth • 2 -chambered heart • Hagfish – no longer considered to be vertebrates by some taxonomists; scavengers • Lampreys – usually parasitic

VI. PHYLUM CHORDATA - Subphylum Vertebrata Class Chondrichthyes • • • Cartilaginous fishes Sharks, skates, rays Well-developed jaws; paired fins Continual water flow over gills Lateral line system (water pressure changes) Internal Fertilization; may be – Oviparous- eggs hatch outside mother’s body – Ovoviviparous- retain fertilized eggs; nourished by egg yolk; young born live

VI. PHYLUM CHORDATA - Subphylum Vertebrata Class Osteichthyes • Ossified endoskeleton • Scales • Operculum • Swim bladder • Ectotherms • Most numerous of all vertebrates • Ray-fined – Most common type; fins supported by long, bony rods arranged in a ray pattern; bass, trout, perch, tuna, herring • Lobe-finned - Fins supported by rod-shaped bones surrounded by a thick layer of muscle; coelocanth; lungfishes

VI. PHYLUM CHORDATA - Subphylum Vertebrata Class Amphibia • • • First tetrapods, land animals Frogs, toads, salamanders Metamorphosis Ectotherms External fertilization; lack shelled egg • Moist skin for gas exchange • 2 → 3 chambered heart

VI. PHYLUM CHORDATA - Subphylum Vertebrata Class Reptilia • • • Lizards, snakes, turtles, and crocodilians Internal fertilization Amniotes – Eggs have shells, extraembryonic membranes which aid in gas exchange, transfer of nutrients, protection Ectotherms 3 -chambered heart in most; 4 -chambered heart in crocs Scales with keratin

VI. PHYLUM CHORDATA - Subphylum Vertebrata “Class Aves” • Have many adaptations for flight – – – – Wings Honeycombed bone Feathers (keratin) Toothless Lack urinary bladder One ovary Large breastbone • Endothermic • 4 -chambered Heart • Fossil studies show connection between reptiles and birds; birds now included in Class Reptilia

VI. PHYLUM CHORDATA - Subphylum Vertebrata Class Mammalia • • Mammary glands Hair (keratin) Endothermic 4 -chambered heart Large brains (relative to size) Teeth differentiation Diaphragm Divided into three groups – Monotremes – Egg-layers; platypus, anteaters – Marsupials – Embryonic development of young completed in pouch; kangaroos, koalas, opossums – Eutherians – Placental

VII. ANIMAL FORM & FUNCTION • Anatomy vs Physiology • Humans are composed of 4 tissue types Ø Epithelial Ø Connective Ø Nerve Ø Muscle

VII. ANIMAL FORM & FUNCTION, cont Epithelial Tissue • Covers body and lines organs and cavities • Forms glands • May secrete mucus, be ciliated • Held together by tight junctions • Basement membrane Ø Anchors one side of epithelium to tissues beneath Ø Extracellular matrix made up of protein, polysaccharides • Classified according to the number of layers of cells Ø Simple - single layer of cells Ø Stratified – multiple layers • And the shape of the cells Ø Squamous Ø Cuboidal

VII. ANIMAL FORM & FUNCTION, cont Connective Tissue • • • Bind and support other tissues Consists of cells loosely organized in an extracellular matrix Matrix is produced and secreted by cells

VII. ANIMAL FORM & FUNCTION, cont Nerve Tissue • Senses stimuli and transmits signals from 1 part of the animal to another • Neuron Ø Dendrites Ø Cell Body Ø Axon

VII. ANIMAL FORM & FUNCTION, cont Muscle Tissue • Capable of contracting when stimulated by nerve impulses • Myofibrils composed of proteins, actin and myosin • 3 Types of Muscle Tissue Ø Skeletal – Voluntary, striated Ø Cardiac – Involuntary, striated, branched; makes direct contact with other cardiac muscle cells

VIII. REGULATION OF INTERNAL ENVIRONMENT • Fluid that surrounds cells is known as interstitial fluid • Temperature, water concentration, salt concentration, p. H must be kept relatively constant to maintain homeostasis • Maintained through Ø Negative Feedback – Triggers response that counteracts the change Ø Positive Feedback – Triggers response that amplify the change

VIII. INTERNAL ENVIRONMENT REGULATION, cont Osmoregulation • Management of the body’s water content and solute composition • Animals may be classified as: v. Osmoconformer: Marine invertebrates. Solute concentration in sea equal to that of organism; therefore, no active adjustment of internal osmolarity (marine animals); isoosmotic to environment v. Osmoregulator: Include marine vertebrates, freshwater animals, land animals. Body fluids have solute concentration different from environment. Must expend energy to regulate water loss or gain.

VIII. INTERNAL ENVIRONMENT REGULATION, cont Osmoregulation, cont • Freshwater fishes Ø Higher solute concentration in fish → fish gains water, loses salt → doesn’t drink water, excretes large amounts of dilute urine • Marine fishes Ø Lower solute concentration in fish → fish loses water, gains salt → drinks large amount of saltwater, pumps

VIII. INTERNAL ENVIRONMENT REGULATION, cont Thermoregulation • Regulation of body temperature • Four physical processes: Ø Conduction - Transfer of heat between objects in direct contact Ø Convection - Transfer of heat by movement of air/liquid past a surface Ø Radiation - Transfer of heat between objects not in direct contact Ø Evaporation - Loss of heat in conversion of liquid to gas • Sources of body heat: Ø Ectothermic - Determined by environment Ø Endothermic - High metabolic rate generates high body heat

VIII. INTERNAL ENVIRONMENT REGULATION, cont Thermoregulation, cont. • Adaptations o Torpor - Low activity; decrease in metabolic rate Ø Hibernation § Long-term or winter torpor § Due to winter cold, food scarcity § Bears, squirrels Ø Estivation § Short-term or summer torpor § Adaptation for high temperatures, water scarcity § Fish, amphibians, reptiles Ø Both typically triggered by length of daylight

VIII. INTERNAL ENVIRONMENT REGULATION, cont Thermoregulation, cont. Human Thermoregulation

VIII. INTERNAL ENVIRONMENT REGULATION, cont Metabolism • Sum of all energyrequiring biochemical reactions • Energy measured in Joules, calories, or kilocalories (Calories) • Metabolic rate may be determined by Ø Monitoring rate of heat loss Ø Measuring amount of O 2 consumed or CO 2 produced

IX. ANIMAL REPRODUCTION

IX. ANIMAL REPRODUCTION Asexual • Fission (parent separation) • Budding (sponges, corals) • Fragmentation + Regeneration (inverts) Sexual • Gametes Ø Ovum Ø Sperm • Zygote

IX. ANIMAL REPRODUCTION Mechanisms of Reproduction • Parthenogenesi s Ø Unfertilized egg development Ø Typically haploid, sterile adults Ø Daphnia, Rotifers, honeybees

IX. ANIMAL REPRODUCTION Mechanisms of Reproduction, cont • Hermaphroditism Ø Both male & female reproductive systems Ø Occurs in earthworms, other sessile & burrowing organisms

IX. ANIMAL REPRODUCTION Mechanisms of Reproduction, cont • Sequential hermaphroditism Ø Reversal of gender during lifetime Ø Protogynous - female first Ø Protandrous – male first

IX. ANIMAL REPRODUCTION Sexual Reproduction • Pheromes Ø Chemical signals released by organism Ø Influences behavior, physiology of organisms of same species Ø Active in minute amounts • Fertilization Ø External Ø Internal

X. ECOLOGY Interactions Between Organisms & Their Environment

X. ECOLOGY Important Terms/Concepts • Levels of Organization Ø Organism → Species → Population → • Biomes • Food Chains Ø Trophic levels Ø Importance, examples of decomposers Ø Comparison of energy flow vs recycling of nutrients § Most energy? § Pyramid of production § Limits on trophic levels Ø Primary production provides the “energy budget” for any given ecosystem

X. ECOLOGY Nutrient Cycles • Water • Carbon • Phosphoru s • Nitrogen

X. ECOLOGY Ecological Succession • Changes seen in a community following a severe disturbance Ø Primary Succession § Describes individuals colonizing virtually lifeless area with no soil; may be due to volcano, glacier § Typically begins with autotrophic bacteria; followed by lichens, mosses § Known as pioneer organisms § Gradual development of soil due to weather, decomposition of pioneer organisms § Larger organisms begin to inhabit area → eventually results in climax community Ø Secondary Succession § Results from disturbance that leaves soil intact; for example, fire

X. ECOLOGY Population Ecology • Study of how and why populations change • Survivorship Curves Ø Type I – have few young but provide good care; seen in humans & other large mammals Ø Type II – intermediate; mortality fairly constant over life span; seen in some invertebrates, lizards, rodents Ø Type III – high death rates for very young; typically produce high number of young but provide very little care; seen in fish,

X. ECOLOGY Population Ecology, cont • Exponential Growth Ø Occurs when population is in ideal environment Ø No limiting factors Ø Entire population multiplies by a constant factor • Logistic Growth Ø Population impacted by limiting factors Ø Carrying Capacity is met Ø Limiting factors may be described as § Density-Dependent § Density-Independent

X. ECOLOGY Population Ecology, cont • Life history traits include reproductive age, frequency of reproduction, number of offspring, amount of parental care • Shaped by evolution and natural selection • Selection for life history strategies determined by population densities and conditions Ø r-selection § § § Seen in uncrowded, unpredictable environments Also known as density-independent selection Individuals mature early and/or produce maximum number of offspring at one time Maximizes r, the per capita rate of increase Bacteria, weeds Ø K-selection § Typically seen in larger, longer-lived individuals § Population is close to carrying capacity therefore competitive ability, efficient use of resources favored § Maturity & reproduction at later age § Fewer young; higher degree of parental care § Term, K refers to carrying capacity

X. ECOLOGY Population Ecology, cont Human Population Growth. . . Exponential. . . but, it is slowing