BIOL 111: Lab Midterm 2 Review 12-12-17 12:23 AM LAB 6: INVERTEBRATES I

Phylum Cnidaria • among simplest of animals (only sponges less complex) • cnidocytes – specialized stinging cells, capture prey, defense • mostly marine: for example, jellyfish and corals • 2 cell layers surrounding a central cavity • radial symmetry with arms/tentacles • 2 Forms: 1) Polyp: sessile, asexual (oral above aboral) 2) Medusa: motile, sexual (aboral above oral) *some show both forms in their life cycle: these are dimorphic

Ex. Hydra: -small (3-8mm) freshwater polyp -glides/inches/somersaults/float on gas bubbles -carnivores: tentacles capture prey, subdue with nematocysts stings, partially digested in gastrovascular cavity, absorbed by gastrodermal cells, intercellular digestion occurs

>ANATOMY -hypostome: conical elevation with mouth opening at its tip; mouth = mouth and anus -tentacles: food catching arms, contain cnidocytes -gastrovascular cavity: digestion/absorption, respiration in gastrodermis and epidermis -body column: mesoglea + 2 tissue layers (epidermis and gastrodermis) -mesoglea: thin, gelatinous layer = hydrostatic skeleton (: thin dark line)

-basal disc (foot): posterior end of body, attaches to substrate (ex. Rocks, plants), locomotion

Cell Types: -epitheliomuscular: longitudinal (epi)/circular (gastro), antagonistic à move, engulf partially digested food -cnidocytes: in epidermis, contain nematocysts triggered by cnidocils (bristle-like projections, modified cilia); nematocyst types: stinging/entangling/adhesive -neurons: nerve cells forming a nerve net, runs through mesoglea • sensory cells: type of neuron in epidermis, sensitive to external stimuli

-gland cells: in basal disc’s epidermis (sticky substance) & in gastrodermis (digestive enzymes) -interstitial cells: b/n epitheliomuscular cells, small, totipotent (act like stem cells) à cnido. -ciliated cells in gastrodermis = create water currents à food circulates, also: distributes oxygen and removes wastes -no central nervous system or ganglion: signal sent through entire body

>REPRODUCTION -either sexual or asexual -sexual: sperm + egg = zygote (union of gametes produced in gonads: testes & ovaries) • some (not most) are : able to produce both gametes (m and f) • reproduction occurs in the fall, spermàwateràhole in epidermisàegg • zygote forms hard covering and drops to sediments, remains dormant until spring -asexual: budding of new individual through mitosis (2-4 days), genetically identical • summer months, lots of food, parent surviving? Why change! *two different strategies due to alternation b/n stable and unstable conditions -self-fertilization is not advantageous (doesn’t benefit evolution) • receptor proteins on egg cell membranes recognize sperm from self and rejects it • plants of diff. genotypes have structural differences preventing self-pollination • unknown for hydras

>FEEDING -for the most part, remains stationary until food drifts to it, brushing its tentacles (opportunistic feeders) -bilateral symmetry would be more beneficial: sensory structures concentrated

Ex. Gonionemus -Class Hydrozoa (not Class Scyphozoa, so not technically a jellyfish) -small medusa (d=2.5cm) living in shallow temperate marine waters -some cling to seagrasses their entire life rather than swimming, some are poisonous

>ANATOMY -bell: dome-shaped, epidermis, gastrodermis, mesoglea -tentacles: arms hanging from bell, capture prey, attach to objects, 80+/individual -tentacular bulbs: dark swellings at base of each tentacle, interstitial cells à cnidocytes -adhesive pads: attach to seagrass and macroalgae -cnidocytes: stinging cells, spiral swellings (batteries) along tentacles, each contains nematocysts à projects tube à penetrates prey’s tissue à deliver paralyzing poison -velum: shelf under the bell, jellyfish don’t have a velum, epitheliomuscular cells here contract = move -manubrium: tube hanging in bell, homologous to hypostome in hydra, dark square, extracell. digest. -mouth: end of manubrium, ingestion, ringed by oral lobes (fleshy projections), ingestion, anus too -radial canals: 4 canals/extensions of stomach, radiate from manubrium -ring canal: connect w/ radial canals, runs around edge of bell, intercellular digestion -statocysts: small swellings b/n tentacles’ bases, contain stones, orientation à gravity, sensory -gonads: 4 light brown gonads hanging down as ruffles, parallel to 4 radial canals

Phylum Annelida • annelida “little rings” • earthworms, tubeworms, leeches = segmented worms • bodies composed of similar segments, ringed appearance and septa internally

Ex. Earthworm (lumbricus terrestris) -live in moist oil w/ lots of detritus for food -burrowing à soil is partly pushed and partly swallowed à break up soil particles -soil à digestive tract à cement utilized in lining burrows à air and water à thicker rich topsoil -anterior initiates stronger response due to greater concentration of ganglion

>ANATOMY (External) -thin transparent cuticle covers outer surface of worm, secreted by epidermis, protects from desiccation -mucus secreted by glandular cells in epidermis = protective layer, locomotion, respiration -bilateral symmetry: anterior (slightly more cylindrical, thicker), posterior, dorsal (back), ventral (lighter colour, more flattened, small pores visible here) -clitellum (thick band) located closely to anterior end -4 pairs setae on each segment, except first and last (one pair ventral, one pair lateral), 100 segments -Segment 1: mouth, prostomium – fleshy lobe preceding mouth, peristomium – portion around mouth -Segment 9 & 10: ventral, 2 pores/segment à seminal receptacles (store sperm) -Segment 14: ventral, 2 pores = female genital pores -Segment 15: ventral, 2 pores = male genital pores, seminal grooves à sperm à clitellum -Segment 26: ventral, genital setae (hold ventral surfaces together during ) -Segment 32-27: clitellum secretes mucus cocoon where eggs and sperm are deposited -Final segment: anus (pore) *annelids have a complete digestive tract w/ mouth and anus separate

>LOCOMOTION -circular and longitudinal muscles cause movement -antagonistic muscle types & hydrostatic skeleton -circular muscles contract à pressure on fluid in coelom à segment elongates à push anterior segments forward à longitudinal muscles contract à segment shortens à pull posterior segments fwd -setae anchor segments when others are lengthening and shortening

>CIRCULATORY SYSTEM -closed circulatory system -dorsal blood vessel = thin dark purple line, largest blood vessel in body -ventral blood vessel on other side, dark in colour, smaller than dorsal vessel • in each segment: branches of ventral vessel form capillary beds à body à dorsal branches -dorsal blood moves anteriorly, ventral blood moves posteriorly -5 pairs aortic arches: encircle esophagus, act as the heart (pumping organ) -one-way valves for dorsal blood (less pressure so more chance for backflow)

>ANATOMY (Internal) -septa: semi-transparent, mark boundaries of each segment -coelom: fluid-filled body cavity, divided by septa, acts as hydrostatic skeleton -all segments (except anterior ones) each contain a portion of the digestive, excretory, nervous, and circ -Digestive system: • digestive tract runs down middle of body, mouth à anus • pharynx: light-coloured swollen structure, pulls soil into digestive tract, radial muscles dilate the pharynx to help ingest detritus • esophagus: thin-walled, lies under aortic arches, partially covered by white reprod. organs • : storage pouch, dark-coloured, thin-walled • gizzard: grinds up food, light-coloured, muscular • intestine: long, straight tube extending from gizzard à anus, food & water absorbed • typhlosole: dorsal infolding of intestine running down length of worm, increase area

-: -hermaphrodites: both m and f gonads are present in each individual -copulation external, on warm, moist nights -seminal vesicles: male repro, 3 lobes, sperm storage -testes: segments 10 & 11, sperm à sem. ves à vas deferens à m genital pores seg. 15 -ovaries: very small, eggs à oviducts à f genital pores -seminal receptacles: f repro, segments 9 & 10, tiny, round sacs, light-coloured, ventral

Copulation: -earthworms lie with ventral surfaces together -anterior ends facing opposite directions -mucous produced by clitellum helps to hold -sperm à seminal grooves à seminal receptacles -2 to 3 hrs -clitellum secretes cocoon made of chitinous material, anterior segments produce mucous tube -eggs released from female genital pores into cocoon à anteriorly à eggs fertilized as they pass over seminal receptacles *fertilization is EXTERNAL à cocoon slipped off à hardens and shrinks on earth’s surface (small seed)à 1 week development, only one individual will complete development

> RESPIRATORY SYSTEM -no lungs/gills, no specialized organs -oxygen and carbon dioxide exchanged in capillaries distributed throughout moist epidermis

>NERVOUS SYSTEM -pair of ganglia (ganglion): cluster of neurons called the cerebral or suprapharyngeal ganglia • dorsally located, just anterior to pharynx (seg 3) • main center for coordination of sensory & motor functions -subpharyngeal ganglia: below pharynx (seg 4), embedded in pharyngeal muscles, motor functions, reflexes (without these ganglia, movement stops) • without the supra. experiments: still moves, cannot coordinate with environ. stimuli • brain regenerates itself in 2 months -ventral nerve cord: ventral to ventral blood vessel, thin tan string, ganglion (swelling) in each seg -segmental ganglion: 3 pairs segmental nerves à each seg, coordinate muscle contractions, small -sensory receptor cells: in epidermis, receive sensory info (light, chemicals, pressure), microscopic

>EXCRETORY SYSTEM -paired organs repeated in every segment - picks up chemicals from coelomic fluid and capillaries à nephridiopore in body wall • small, irregularly shaped tubes

Cross-Section: 1) Body wall -cuticle, epidermis, circular & longitudinal muscle layer *like in the Hydra 2) Coelom -space 3) Intestine -digestive space -typhlosole -dorsal & ventral blood vessel

Vermicomposting (“vermi”=worm) • raw organic materials + minerals à nutrient-laden worm castings à humus for growing plants 1) Container/box: shallow, 30cm, retain moisture, keep out light, drainage holes 2) Bedding: shredded newspaper, decomposed leaves, peat moss (acidity, moisture retaining) 3) Redworms: worm to food waste ratio of 2:1, red wigglers/fishworms, 1.5kg worms, worm castings more fertile than soil (5xN, 7xP, 11xK, 3xMg, 2xCa) 4) Food waste: banana peels, coffee grinds, fruits, veggies, plate scrapings, egg shells, spoiled food • no animal products (ex. Cheese, bones, oil, meat) à putrefaction à odour (proteins break) 5) Controlled environment: temp (0 to 32 celsius okay; best is 13-25), moisture, acidity, ventilation • add water when necessary: gas exchange through moist skin only 6) Maintenance: regularly digging and burying food waste, harvest worms at the end, use castings within 3 months from start, add fresh bedding (1cm/week), divide bedding à little piles à shine light 12-12-17 12:23 AM

LAB 7: INVERTEBRATES II

Phylum • second (to arthropods) in species diversity and number • , , shellfish: clams, mussels, oysters, highly mobile octopus and squid • all lack segmentation • open circulatory system (except for cephalopods)

Ex. (Cantareus asperses) -native to Europe -temperate climates -herbivores -no

>ANATOMY (External) -shell: calcium carbonate, proteins (secreted by ) • dextral: clock-wise twirling (most common) • sinistral: counter-clockwise • secrete new shell layers: “growth rings” are visible -foot: locomotion, specialized glands à mucous (to grip and glide) • mucous trails are common in gardens • chemicals alert conspecifics (own species members) to location o food source • mucous reduces water loss, allows for strong adhesion, and forms egg cases -tentacles: 2 pairs on head for olfaction (taste/smell) • inferior tentacles: ground chemicals • superior tentacles: airborne chemicals, eyes • chemoreceptors located in epidermis

>LOCOMOTION -monotaxic*: extend across width of foot *snail -ditaxic: alternate b/n right and left sides -same direction of locomotion: posterior to anterior; opposing direction: anterior to posterior -direct waves*: lifting posterior edge, forward placement, forward contraction -retrogade waves: lifting anterior edge, stretching and attaching, backward contraction Taxis: movement in particular direction (+ towards, - away from) -phototaxis: snail doesn’t care -geotaxis: negative geotaxis (protect from drowning in low elevation) -chemotaxis: actively search for food, relying on olfaction

>RESPIRATION -aquatic mollusks: gills -terrestrial mollusks: exchange gas across mantle, surface must remain moist, desiccation = prob -Pulmonates: highly vascularized mantle cavity = primitive lung - is a pore that opens and closes with breathing

>REPRODUCTION -: both female and male parts -sexuall mature snails release chemical attractants called pheromones -ritualized courtship à touching of tentacles/feet (hrs) à copulation -exchange sperm packets, which are then stored until snail is ready to fertilize its eggs -polygamous : individuals receive sperm from 1+ mate -before copulation, sperm donor releases a love dart from the genital pore à recipient -dart coated with special mucous (improves survival of sperm)

Phylum Arthropoda • most complex and diverse of invertebrates • bilateral symmetry • segmentation • cephalization – sense and control organs (focused at anterior) • exoskeleton • jointed appendages • crustaceans: highly adapted to aquatic life • shrimp, lobsters, daphnia, crayfish

Ex. Crayfish -freshwater lakes and streams, “crawdads” -most active at night -opportunistic feeders: algal plant, tadpoles, benthic (bottom-dwelling invertebrates), fish eggs -short-lived (2-3 yrs)

>ANATOMY (External) -bilateral symmetry: like in Annelida, unlike radial sym of Cnidaria -hard cuticle made of chitin: organic compound secreted by underlying epidermal cells, calcium carbonate hardens it, protection/exoskeleton, inextensible, regular molting à growth -body regions: • head & thorax (8 seg) = cephalothorax (covered by carapace, fused dorsal shield) with cervical groove dividing 2 regions • compound eyes (>1 lens, unique to arthropods) on head, separated by rostrum • gill chamber contain gills • abdomen (6 seg): ½ total length -body segments: body à regular segments, junctions covered by thin flexible chitin -appendages: structural specialization (tasting, feeding, feeling, walking, swimming, mating • similar embryonic beginnings • 3 parts: basal stalk, 2 distal branches (characterize crustaceans as biramous arthropods à antennules, maxillipeds, swimmerets, uropods) • homologous: similar embryos à different uses today • serial homology: similar structures in diff segments, with diff functions

>RESPIRATORY -gill: extend from bases of walking legs, other attached to wall of gill chamber -crayfish can respire on land for a short time (so long as there’s water in the gill chamber) -gills are thin and feathery: enormous surface area à gas diffusion -water stream passes over gills à laden with carbon dioxide à expelled from anterior end

>CIRCULATORY -heart: diamond, whitish, 3 pairs of ostia (holes), directly below thoracic groove of carapace, lies in pericardial sinus (dorsally located space, where blood collects), 7 main arteries -open circulatory system -hemocoel fills with blood -hemocyanin is the oxygen-carrying pigment in blood plasma (Cu instead of Fe)à transparent

>REPRODUCTIVE SYSTEM -external fertilization -male: small testes, looks like strand of tissue • coiled seminal ducts à genital pores (5th pair of walking legs) -female: pinkish ovaries, small or large, full of orange eggs, granular in appearance • ovaries à oviducts à genital pores (3rd pair of walking legs) • seminal receptacle located on ventral surface b/n 4th and 5th pair of walking legs, where females store sperm for months, FALL: mating occurs, SPRING: fertilization • fertilized eggs attach to female’s swimmerets for 6 weeks until hatching • several more weeks: juvenile crayfish à large enough? à survive independently >DIGESTIVE -digestive gland: paired, soft, cream-coloured, located on both sides of heart • food particles from stomach à microscopic tubules of glands à enzymatic digestion, nutrient absorption occur here -stomach: large structure, flanked by bundles of muscles (mandibular muscles); 2 chambers: o cardiac stomach: larger, most anterior, lined with cuticle and chitinous teeth (gastric mill), food is pulverized/strained/sorted o pyloric stomach: indigestible food material is separated out, sent to intestine; digestible material is forced into tubules leading to digestive glands -intestine: waste food materials, straight muscular organ, voided through anus (ventral telson) -mouth: surrounded by appendages that catch and shred food, mouth à esophagus à stomach

>NERVOUS SYSTEM -ventral nerve cord + the brain -2 nerves run posteriorly around esophagus, rejoins to form ventral nerve cord -statocysts: fluid-filled chamber lined with seate + statoliths (sand grains) -movement of sand grains against innervated setae à can detect position (upside down) -inside base of antennules >EXCRETORY -green glands lie below the eyes, circular • remove unwanted substances from blood, excrete waste fluid out the body • nephridiopores: holes located on a small, conical elevation at base of antennae

>MUSCULATORY -largest muscles located in abdominal region -flexor & extensor muscles work antagonistically à movement -rapid movement: extend abdomen, uropods, telson + suddenly flexing under the body -more controlled movement: muscles within walking legs -abdominal extensor muscles: paired, long, dorsally located, straighten ab region -abdominal flexor muscles: flank intestine, overlying blood vessel located along midline, flex/curl ab region 12-12-17 12:23 AM

LAB 8: FISH

Vertebrate Behaviour • Animal behaviour – observable movement in an animal’s body, response to int./ext. factors • Most behaviour = highly stereotypic: almost always the same, species-specific, not learned

Ex. Beta fish/Siamese fighting fish (Betta splendens) -aggressive, live in stagnant/swampy waters in SE Asia -nest of bubbles among floating plants -females approach a male with a nest, spawns with him. Eggs à bubble nest. Chase away others. -domestication à long fins, bright colour, aggression -well adapted to survive in low oxygen conditions: labyrinth organ above gills (special air- breathing structure) = air space surrounding highly vascularized extension of gill arch • Lungfish also breathe air through gas exchange in paired swim bladders -male vs. male encounter: flare operculum and gill (branchiostegal) membrane, bite bodies -Experiment: • Number of attempted bites • Latency of first attempted bite • Amount of time spent 1 fish length away from opponent -presence of audience member (m or f) affects behaviour of male vs. male

Ex. Yellow Perch (Perca flavescens) -body: 3 parts à head, trunk, tail -gill opening marks border b/n head and trunk -small teeth: unable to eat large prey, pick food off surfaces -carnivores: insect larvae, small crayfish, snails, small fish -mouth: maxilla & mandible (prevent escape of food than for biting), terminal (overtakes prey), inferior (ventral) à bottom feeder, superior (dorsal) à surface feeder -body covered with hard ctenoid scales • arranged to assist streamlining • point backwards • each scale is overlapped by those anterior and dorsal to it • annuli (growth rings), ctenii (small comb-like teeth) • thin covering of epithelium over entire scale -external nares: 2 pairs nostrils, open into olfactory pits (smell), not connected to resp. system -opercula: gill covers, protection for resp structures, pumping system à water forced over gills • 4 gill arches, each bearing 2 rows of gill filaments

-fins: membranous extensions of epidermis, supported by fin rays • 2 groups: 1) unpaired fins: stabilization, forward propulsion a. anterior dorsal fin (spiny rays) b. posterior dorsal fin (soft rays) c. anal fin (spiny and soft rays) d. caudal fins: forward propulsion (soft rays) 2) paired fins: braking, turning, prevent from rolling a. pectoral fins (homologous with forelimbs of tetrapods) b. pelvic fins (homologous with hind limbs of tetrapods) -lateral line: runs along either side of body, small perforations connected to small, water-filled canal; neuromasts are sensory organs within the canal; hair cells are clusters of ciliated sensory receptors à cilia embedded in cupula (gelatinous capsule), which extends into lateral line canal, bending with water disturbance • neurons synapse with hair cells à depolarize à info to brain • cilia arrangement is asymmetrical • lateral line system allows fish to detect disturbances in water • allows fish to locate predators, prey, and social partners • lateral line important in schooling fish (sharp turns) *amphibians also have lateral lines • aquatic larval stage

>ANATOMY (Internal) -vertebral column: vertebrae, chain of small bones, strong yet flexible support • neural spine (spike of bone on each vertebra) -ribs: 2 sets of ribs: ventral (large protective cage) and dorsal (extremely thin) *unique to bony -muscles are divided into myomeres, vertical segments shaped like side-ways “W”s • muscle fibers are firmly attached to myocommata (connective tissue b/n myomeres) • myocommata connected to vertebral column & ribs • majority of muscles are located in the tail and trunk regions: swimming • muscles supported by haemal spines projecting from vertebral column

-liver: large orange-brown mass, stores glycogen, produces bile • bile is released by gall bladder into the intestine à emulsifies fats -stomach: joined by the intestine: at this junction, there are 3 short, finger-like projections: • pyloric caeca: aid in digestion (enzyme secretion, nutrient absorp.) can be very long -mesentery: thin connective tissue holding internal organs together • spleen is in the mesentery; it is small, long, and reddish o reservoir of blood, destroys RBCs (thus red) -coelom is lined by peritoneum (thin, shiny layer of connective tissue) • air bladder (swim bladder): large, elongated sac, whitish o changes in buoyancy à gas gland -kidney is a long reddish-brown strip along vertebral column • filters out metabolic wastes à excretes them in urine • kidney ducts carry urine to urinary bladder à wastes à urinary pore in the urinary papilla (external projection of the male urinary bladder)à environ. • female: urinary bladder incorporated into oviduct, forming a urogenital sinus that expels excretory materials through a urogenital pore • the bladder is small because: freshwater fishwater and amphibians pee more often to get rid of excess water, pee has ammonia (toxic) and it’s expelled quickly

>REPRODUCTION paired testes are greyish-white and filled with sperm • vas deferens: duct lying inside each testis • 2 vas deferens join to form the genital sinus (space) à genital pore à exterior -ovaries fuse during embryonic development à one large structure • orange pink, thousands of ova, eggs à oviduct à genital pores à exterior -external fertilization • eggs released by female into water, male fertilizes them • oviparous: egg-laying, no parental care • egg + yolk à nourishment for embryonic development • in SPRING, depositing thousands of eggs (10-40K eggs) • eggs hatch within 8-21 days >CIRCULATORY SYSTEM -single cycle: blood à heart à gills à body tissues à return to heart -heart has 2 chambers: atrium and ventricle • atrium receives blood from sinus venosus, which receives blood returning from body via the R and L common cardinal veins • blood flows from sinus venosus to atrium à ventricle • atrioventricular b/n atrium & vent prevents back flow when ventricle pumps • ventricle (thick muscular walls, pyramidal) pumps blood out via bulbus arteriosus • afferent branchial arteries (8 branches) go off the ventral aorta à gill arches à capillaries à gill filaments à join branches to efferent branchial arteries • blood passes through gills: picks up carbon dioxide and wastes à water over gills • oxygen is picked up from water • efferent branchial arteries carry blood to dorsal aorta & internal carotid arteries o dorsal aorta continues posteriorly as the caudal artery through haemal arches in the tail à supply oxygenated blood to organs and muscles o internal carotids à oxygenate the brain • common cardinal veins carry oxygen-depleted blood back to heart

A- ventral view of heart and vessels B- sagittal section of heart

>NERVOUS SYSTEM • brain & spinal cord encased by protective coverings: skull & vertebral column • jawless and cartilaginous fish: cartilage, not bone • 2 sound-detecting systems: lateral line & inner ear o ciliated cells detect changes in vibrations o inner ear (ray-finned fish) 1) otoliths, ear stones encased in saccule (fluid-filled sacs), vibrate from sound waves transmitted through water à stimulates sensory cells à neurons à brain interprets impulses as sound *otoliths have growth rings (determine age) o in some fish species: air bladder is connected to inner ear à sound is amplified (sensitive to high frequency sounds) 2) semicircular canals: balance & orientation, 3 pairs of fluid-filled tubes *similar to statocysts in crayfish and Gonionemus • vertebrates’ brain: anterior enlargement of spinal cord • formed by folding of embryonic tissue à as a result: hollow regions (unlike CNS of invertebrates) • 3 major regions: 1) forebrain: olfaction 2) midbrain: vision 3) hindbrain: hearing • embedded gelatinous material surrounded by meninges (pigmented membrane)

• BRAIN: • Optic lobes: visual perception, optic nerves cross and attach to eyes • Telecephalon: like cerebrum in mammals • Olfactory lobes: olfaction, olfactory tracts travel to nares • Auricular (acoustic) lobes: hearing, connects with inner ear • Cerebellum: singular (unlike in mammals)

*large optic lobe because they are visual predators • use sight to find prey • preyed on by visual predators • feed beter in clear water 12-12-17 12:23 AM

LAB 9: ANIMAL PHYSIOLOGY & EVOLUTION

Aquatic Invertebrates: Metabolic Physiology • Cladocerans o small aquatic crustaceans, Phylum Arthropoda, Class Crustacea o “water fleas” – swims jerkily o important component of food web: act as food for other invertebrates (ex. Hydra, fish), feed on phytoplankton and bacteria (suspended in water column) o bioindicators of water quality

Ex. Daphnia (Daphnia magna) • Largest of daphnia species, clear carapace • Freshwater ponds & streams in Western Canada >ANATOMY -compound eye: single eye -carapace: clear exoskeleton, molted, dorsal hinged, gas exchange under carapace -antennae: oars, large and biramous (branched) -posterior spine: long (length can change w/ season), reduces chance of being eaten -digestive tract: C-shaped gut, colour=food -heart: transparent, open circulatory system -thoracic legs: 5 pairs, generate water currents, filter feeding (food trapped on filtering setae/hairs on legs) -post-abdominal claw: remove debris under carapace -brood pouch: 2-20 eggs (parthenogenesis), dorsal sac at end of oviduct Parthenogenesis – development of egg without fertilization by sperm à summer & favourable: females à fall and unfavourable: males (sexual w/ f) -prior to death: females produce thick protective layer around brood chamber (2 eggs) à sac is molted and remains in sediment (up to 20 yrs) until environmental conditions are favourable Temperature & Metabolic Rates • Ectothermic – heat comes from external sources (ex. Daphnia) • Endothermic – generate heat internally (ex. Birds and mammals)

• Homeothermic – able to thermoregulate (maintain body at fairly consistent temperature) • Poikilotherms – cannot thermoregulate (temp fluctuates) ex. Daphnia o Temperature decreases à metabolic demands decrease à heart rate decreases

• Calculating Q10: • Internal temp of organism affects rate of chemical reactions within its body o Most evident in ectotherms

• Q10: sensitivity of a reaction to temperature

• Q10 = RT/RT-10 o Rt: rate of reaction at one temp | Rt-10: rate of reaction at 10 degrees lower • Q10 = 1: temperature does not affect rate of reaction • Q10 = 2: rate of reaction doubles with increase of 10 degrees *daphnia die at temp of 40 degrees Celsius (proteins denature)

Experimental Evolution Evolution takes take time to occur à computer modeling Adaptive change & evolutionary diversification (one species à several species) Evolutionary mechanisms: 1) Natural selection (survival) 2) (mating) 3) Mutation 4) Dispersal

14 finch species on Galapagos, which all evolved from a common ancestor different beak size and shape suitable for different food sources (changing with climate) • ex. Drought à no small/soft seeds à large-beaked birds lived on large/hard seeds • Result: evolution of larger beaks Evolution of new species: one group finches exposed to 2 different food types à 2 forms Females tend to mate with males having the same beak size Conditions that aid adaptation to changing food resources 12-12-17 12:23 AM

LAB 10: MAMMALS

Ex. Rat (Rattus norvegicus) Originated in China, found all over the world in urban areas Selective breeding à diff colour varieties, lab research, household pets Alberta: rat-free zone

>RESPIRATORY -diaphragm: muscle sheet, floor of thoracic cavity, dome, radial arrangement of muscle • Inhale: diaphragm contracts (flatten) & pull down, intercostals contract • Exhale: diaphragm relaxes and goes up, intercostals relax and come in • Only found in mammals, divides anterior & posterior cavities -thoracic cavity is lined w/ pleural membrane -thymus gland: on top of heart, light brown, immune system (lymphocytes mature into T- cells) -trachea = windpipe, cartilage rings à 2 bronchi à bronchioles à alveoli (air sacs) >DIGESTIVE SYSTEM

-huge front incisor teeth, tongue, palate (roof of mouth), small back molars (grinding) -esophagus: glottis covers trachea, guarded by epiglottis (tissue flap=no enter resp) • Pierces diaphragm à stomach -organs suspended by mesentery (tissue sheet) continuous with peritoneum of ab cavity -liver lobes cover the stomach (liver only anatomically related tos mall intestine not stomach) • Stomach = storage + digestion (chemical and mechanical) • Glands line the stomach and secrete juices (zymogens à enzymes that breakdown proteins, activated by HCl) *normally inactive to protect stomach lining • Spleen: brown, L of stomach, accessory to circulatory system, blood reservoir, destroys damaged erythrocyte -stomach opens into small intestine through pyloric sphincter (muscular valve) • Duodenum (liver and pancreas via ducts), jejunum, ileum • Chemical digestion and nutrient absorption • Villi: small finger-like projection, increases surface area -digestive tract walls: smooth muscles, longitudinal and circular, peristalsis (period contractions) -ileum opens into colon through ileocolic valve • Colon: water absorption, fecal formation, caecum (large sac) in herbivores/appendix o Caecum: +/+ symbiotic relationship w/ bacteria, producing cellulase Ascending, transverse, descending colon à rectum à anus *coprophagy – eating own feces, guinea pigs/hamsters/rabbits, caecumànutrition -pancreas lying in mesentery, 2 major roles: 1) Endocrine gland: insulin, other hormones 2) Digestive gland: enzymes, sodium bicarbonate (neutralize acidic secretions entering small intestine, triggered by receptors in small intestine – low pH) -liver secretes bile: bile salts (emulsifies fats), bile pigments, cholesterol • Bile stored in gall bladder

>UROGENITAL SYSTEM -urinary (excretory) + genital (reproductive) system *male urethra and penis FEMALE -urinary bladder: small muscular sac -renal cortex (outer) & renal medulla (inner) -calyx (central reservoir of kidney) -adrenal glands: endocrine system • hormones (ex. Adrenaline) -vagina divides into 2 uteri -oviducts = fallopian tubes • not connected to ovaries directly • peristalsis assists egg movement • fertilization occurs here, endometrium nourishes embryos, placentas & umbilical • estrus: lining in uteri fills with blood, prepared for pregnancyànone? Uteri shrink MALE -penis, scrotal sac (pocket of abdominal wall) à testes à cooler -testis filled w/ seminiferous tubules which produce sperm (meiosis) -epidydymus (coiled): sperm mature -epidyd à vas deferensà urethra -junction of vas def + urethra: glands producing nutrients/sperm additives • Seminal vesicles • coagulating glands • prostate glands • preputial glands) -sperm + additives = semen seminal fluid -adrenal glands lie on top kidneys

*Male rats = 2 openings (anus, urethra) Female rats = 3 openings (+vagina) *Male perch = 3 openings (anus, urinary pore, genital pore) Female perch = 2 openings (anus, urogenital pore)

>CIRCULATORY SYSTEM • blood = liquid tissue, nutrients, oxygen • Heart • Double circuit in mammals • Surrounded by pericardium (sac) • Septum: muscular wall dividing L and R sides • Coronary arteries/veins serve the heart itself • Crayfish: single chamber, hemolymph through open circ • Earthworm: aortic arches, closed circ system • Fish: 2 chambers • Frogs: 2 atria, 1 ventricle • Reptiles: 2 atrai, partially divided ventricle • Birds and mammals: 2 ventricles, 2 atria | R=deoxy, L=oxy • SA node in right atrium à AV node lying b/n septum above ventricles à ventricles • AV valve prevent backflow of blood into atria 3 Types of Blood Vessels: 1) Arteries -thick walled, elastic -away from heart -high pressure -pulse (carotid, brachial) 2) Veins -thin walled, non-elastic -towards heart -low pressure -valves 3) Capillaries -microscopic, one cell thick -nutrient/gas/waste exchange -lymphatic system: plasma lost by capillaries à circ sys

*see major veins and arteries in attached sheets

The Arteries of the Pulmonary Circulation

The pulmonary artery (blue) that emerges from the anterior extremity of the right ventricle, ventral to the root of the aorta. It curves dorsally around the left side of the root of the aorta and ends by branching to form the right and left pulmonary arteries. The left pulmonary artery is very short. It enters the root of the left lung almost immediately. The right one is somewhat longer and enters the right lung.

>Explain why the pulmonary artery may be filled with blue latex, while the systemic arteries are filled with red latex.

Red latex is injected in the systemic arteries and blue latex is injected in the systemic veins to make their identification easier. Commonly the blue latex is injected into one of the thoracic veins (e.g., jugular) returning to the heart. The blue latex would travel through the heart (RA à RV) and then out the pulmonary arteries to the lungs. The latex is too thick to travel through the capillaries in the lungs and thus stops there.