BIOL Midterm Review - Lecture notes 1-10 PDF

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Natural History Observational science studying fauna and flora in the real world One who studies this is called a ANIMAL DEFENCES Background Matching Body has the same form of patterns as the whole environment around them Ex: the has vertical stripes to match the cattails of its marsh environment Di...

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Natural History - Observational science studying fauna and flora in the real world - One who studies this is called a naturalist ANIMAL DEFENCES Background Matching - Body has the same form of patterns as the whole environment around them Ex: the A  merican Bittern has vertical stripes to match the cattails of its marsh environment Disruptive Pattern - Patterns which break up the body shape and make the animal less obvious - Coincident Disruptive Colouring i s when the patterns on different body parts match up to create one solid pattern when the animal is in a certain position Ex: S  ongbirds have striped heads which make their head shape less visible Bicolouration - Animals are coloured in order to be camouflaged from two different perspectives Ex: W  hirligigs are white on the bottom to blend into the sky for fish, and black on top to blend into the water for birds, as they swim on the surface of the water Countershading/Self-Shadow Concealment - Animals are lighter in areas where shadows will fall in order to hide body dimension - Light is casted on darker areas and shadows cover lighter areas in order to make the animal look uniform Ex: W  hite-Tailed Deer are lighter on their bellies as the light tends to hit their backs Mimicry - Animal uses body shape, colour, or structure to copy something else in order to protect themselves or make themselves undesirable to predators Ex: T  reehopper’s shape makes them look like the thorns of plants that they rest on Masquerade - Animal’s body shape is changed into something which matches a part of the environment to make the animal look inedible Ex: W  alking Sticks are twig mimics and blend into tree branches Startle Patterns - Brightly coloured parts of an animal which appear when they are threatened - Startle the predator, giving the animal a chance to escape Ex: U  nderwing Moths have bright hind wings that open when they are under threat

Distraction/Deflection Patterns - Brightly coloured patterns on non-vital parts of the animal to draw predatory attention - The animal can survive without the areas of the body with these patterns Ex: Underwing Moths can survive without their hind wings Startle Structures - Parts of the animal that come out when it is threatened to startle predators Ex: S  wallowtail Caterpillars shoot out bright red forked glands called osmetarium Startle Sounds - Animal makes a sound in order to scare a predator away Ex: B  eavers slap the water with their tails Body Armour - Structures which shield the soft and vulnerable parts of the body - Usually made of calcium, can be an exoskeleton Ex: M  illipedes, Snails, Turtles, Clams, all have hard shells to protect their bodies Soft Structures - Hairs or fibres which make the animal unappealing or difficult to eat - Some hairs are modified into quills or spines Ex: E  astern Tent Caterpillars create silk tents, Wooly Bears are covered in hairs Sequester - Acquire something in the diet and store it in the body for use Ex: M  onarch Butterflies eat Milkweed leaves that contain terpenoids Poison Spines - Stiff hairs which are branched and tipped with toxins Ex: I o Moth Caterpillars have large green spine clusters which inject burning toxins Stingers/Injectors - Some animals have stingers which have toxins that make skin burn and itch Ex: Y  ellow Jackets have stingers which inject toxins Poisonous Skin - Some animals have skin which is coated in toxins or secretes toxins Ex: R  ed Efts have poisonous skin, Blister Beetles secrete terpenoids.

Spray - Some animals spray chemicals which are foul, dangerous, or surprising, so as to deter predators Ex: S  kunks shoot out a sulfur alcohol from anal glands, Bombardier Beetles shoot out hot quinone gas Aposematic Colouration - Bright or highly visible coloration on animals which warns that they have defences - Night active animals tend to have black and white colouration which stands out in the dark - Day active animals tend to have very bright colours that are very eye-catching Ex: Striped Skunks are black and white, Salamanders are bright blue Mullerian Mimicry - Animals that have similar aposematic colouration and all bear some sort of defence Ex: Yellow Jackets and Honeybees Batesian Mimicry - Animals which have similar colouration and appearance where some animals are harmful (models ) and some are harmless (mimics) - Models highly outweigh mimics, all species must occur at the same time of year Ex: Viceroy Butterflies mimic Monarch Butterflies, which are poisonous Aggressive Mimicry - An animal uses mimicry to obtain a meal Ex: Female F  ireflies mimic the mating flash patterns of the other species in order to attract a male which they then eat Bluffing - Puffing up the body in order to appear larger and intimidate predators Ex: A  merican Toads fill their throats with air to enlarge, Hognose Snakes flatten out Thanatosis - Playing dead in order to deter a predator Ex: H  ognose Snakes, Opossums Behavioural Group Defence - Animals gather in large numbers to reduce individual chances of being preyed upon - Visually confuses predators by using murmuration Ex: W  hite-Tailed Deer gather in yards, Birds gather in flocks

Aggressive Group Defence - The normal prey band together in large groups in order to take out a threat Ex: Y  ellowjackets release attack pheromones to call other wasps to attack Mobbing - Birds give alarm calls in order to summon a group to attack a predatory bird Ex: B  lue Jays mob owls in their areas to make the night safer Bodyguards - Animals are guarded by more powerful animals, usually in a mutual relationship Ex: C  arpenter Ants guard Aphids as they produce sap that the ants eat Defence Advertisement - Bright white colouration when running away to notify predator that they are seen - May cause distraction in the predator Ex: C  ottontail Rabbits raise a white tail when they are running away ANIMAL VIGILANCE Olfactory - Enhanced sense of smell to smell danger, food, and mates - Scents are analysed in the J acobson’s Organ - Mammals expose this organ using Flemen (opening their mouth while smelling) Ex: Moose have a very large snout and lick the air to smell better Visual - Eye placement and internal structure allows for better sight to scan the environment - Nocturnal animals have more R  ods in their eyes and a light-reflective layer called the Tapetum Lucidum in order to ameliorate their night vision Ex: F  oxes (predators) have frontward eyes, Ducks (prey) have side eyes Auditory - Ears are large and able to pivot in all directions for better aimed listening Ex: M  oose have large pivoting ears and antlers which enhance sounds PLANT DEFENCES Body Armour - External shells or coats which protect the insides of the plant Ex: T  ree Bark, Acorn shells with seeds on the inside

Harmful Structures - Parts of a plant which make it unpleasant or unsafe for animals to eat - Thorns are modified branches - Spines are modified leaves - Prickles are epidermal outgrowths similar to hair Ex: H  awthorn Bushes are covered in sharp thorns that harm animals trying to eat them Trichomes - Plant hairs which make it difficult for small animals to walk on the plant - Glandular Trichomes are not poisonous but give sting and irritation to the skin Ex: S  tinging Nettles have chemicals which cause a burning sensation Inducible Defences - Defences which are only produced under certain conditions in which they are needed - Phytohormones are sent out in order to release chemicals to deter an attacker - Wounded leaves send out wound hormones Ex: W  ater Smartweed grow trichomes in the dry season to deter land predators Structural Digestibility Reducers - Parts of a plant which make digestion of the plant difficult - Cellulose, Hemicellulose, and Pectin make plant tissue hard to eat - Lignin r einforces, makes leaves stiff and gives nuts a shell - Silica is hard for animals to digest Chemical Digestibility Reducers - Chemical aspects of a plant which inhibit digestion - Tannins are secondary metabolites and are astringents which dry the mouth - Calcium Oxalate Crystals b  urn the mouth and tear the digestive tract Ex: A  rum Plants ( Skunk Cabbage ) have calcium oxalate crystals in their leaves Terpenoids - Organic compounds found in resins which taste very bitter and do not contain nitrogen Ex: P  inecones have resin on them Alkaloids - Organic compounds containing nitrogen which bind to digestive enzymes to inhibit digestion - Some are sugar mimics Ex: B  uttercups and Asters contain alkaloids

Insect Hormones - Hormones secreted by plants which affect insects eating it in a negative way - Phytoecdysones cause caterpillars to moult early and die ( R  ock Polypody ) - Phytojuvenile Hormones c ause caterpillars to stay in an age unable to reproduce ( Balsam Firs ) - Phytoestrogen o  verload the animal with reproductive hormones, inhibiting reproduction ( Subterranean Clovers ) - Phytotoxins m  igrate under the skin to make it more sensitive to sunburn Odour Defences - Plants advertising a chemical defence by emitting a foul odour to deter animals Ex: M  ustards emit a strong odour Aposematic Colouration - Immature seeds are coloured differently than mature seeds and contain terpenoids - Sugar is produced around mature seeds and colour change indicates ripeness Ex: B  lueberries are green while the seed is developing, and blue once it is ready for dispersal ENVIRONMENTAL STRESSORS Sub-Zero Temperatures - Endotherms Outside Protection - Mammals grow longer and thicker guard hairs, dense underfur - Birds grow bulkier contour feathers and have down feathers close to the body Inside Protection Subcutaneous Fat sits beneath the surface for insulation to hold in body heat Brown Fat is more internal fat which is burned for warmth - Birds lack brown fat but add subcutaneous fat for fuel Thermogenesis - When animals shiver in order to burn fat for warmth Gloger’s Rule - Pale colours lack pigment, making them better insulators for cold environments Ex: Snowy Owls, Ptarmigans, and all white in the winter  Arctic Foxes are  Bergmann’s Rule - Animals are short and bulky to lower surface area to volume ratio to conserve heat - Ratio closer to 1 is better Ex: C  aribou have short, large bodies as they live in the north

Allen’s Rule - Extremities are smaller to reduce surface area Ex: P  olar Bears have very small ears Countercurrent Heat Exchange - Blood is cooled towards uninsulated extremities and is warmed going back to the core - Performed in a Rete Mirabile vein and artery network Ex: B  eaver tails, Waterfowl feet, Red Fox snout Heat Preserving Behaviours - Birds tuck extremities under their wings to warm them up - Mammals breathe with their mouths closed in the winter - Small mammals and birds dig into the S  ubnivean Space - Some animals Bask in the sun in order to soak up the heat from the rays Ruffed Grouse bury themselves into the snow for heat Resting Site Choice - Birds roost in dense coniferous trees covered in snow to protect from wind and cold - Some birds nest in trunk holes - Some mammals huddle in nests in the winter to preserve body heat (improves ratio) - Some animals build shelters with thick insulation from mud, sticks, etc Ex: Beavers create lodges insulated with mud, hole in the top for air circulation  Reduction of Body Heat - Animals let their internal body temperature drop for a short time, usually overnight - The less difference between the outside and inside temperature, the less energy is used Ex: C  hickadees go into a very deep sleep known as Torpor Sub-Zero Temperatures - Ectotherms Behavioural Freeze Avoidance - Some animals go below the frost line and become dormant for the winter - Aquatic and semi-aquatic animals go to the bottoms of ponds and breathe through skin using oxygen travelling with the stream - Insects go dormant above the frost line using Cryoprotectants (glycerol) to prevent freezing - Some insects produce O  othechas, hard cases around eggs to protect from winter

- G  arter Snakes go into dens in large numbers, called Hibernaculums Supercooling - The liquid inside an animal is below zero but not frozen due to glycerol

Ex: A  ngle-Winged Butterflies spend winter in their adult stage Freeze Tolerance - Ability to survive winter with ice inside the body in nucleating sites between cells - Cells contain cryoprotectants, ice nucleating sites made by proteins are between them Ex: C  horus Frogs freeze solid in the winter using freeze tolerance Protective Structures - Some animals spend winter in structures which block out harm - They usually freeze and survive due to freeze tolerance Ex: Goldenrod Gall Flies spend the winter in plant Galls as grubs Dormancy Over Winter Lethargy - Light state of dormancy in which the animal is easily roused - Body temperature doesn’t drop as much as it would in hibernation - Heart rate slows down Ex: R  accoons go into tree hollows in the winter to sleep Torpor / Prolonged Lethargy - Deep sleep where body temperature and heart rate decrease - Animal wakes every few days to eat and defecate Ex: B  lack Bears have low heart rates, yet high temperature and are woken easily - Break up branches before winter while fattening up - B  ear’s Nest - Form a rectal plug called a T  appen Hibernation - Long term dormancy in which heart, respiratory, and metabolic rates drop very low - Body temperature falls below 10ºC Ex: J umping Mice are true hibernators Winter Mobility Physical Adaptations - Long legs, larger feet Ex: R  uffed Grouse have scales which grow on their feet in the fall to make feet larger Behavioural Adaptations - Small mammals travel through the subnivean space - Larger animals follow each other’s tracks to conserve energy - Some animals use their body shape to their advantage Ex: O  tters slide on their bellies

Migration Why They Leave - Many birds feed on insects or from the ground, there is a food shortage Ex: Most songbirds eat insects, sandpipers feed in the ground  How They Make The Journey - Fatten up before flying and use subcutaneous fat as fuel - Songbirds add 10% of their weight and fly in short bursts - Sandpipers double their body weight in 10 days - Many migrate at night for fewer threats, cooler temperatures, and calmer winds - Songbirds are night migrators - Some only migrate during the day R  aptors soar up in Thermals created by different heat levels, Thermal Hopping Slotted Feathers on the wings create extra lift S  wallows and Hummingbirds feed while they migrate on flying insects and flowers respectively - Birds navigate using the sun, landscapes, moon, constellations, and magnetic fields Rhodopsin is  a retinal photopigment possibly used to detect magnetic fields - Some birds fly in a V-Shape in order to preserve energy and lift How Humans Research Migration - People tag birds to do research on their behaviour in the process of B  anding - Birds are captured in fine nets called M  ist Nets - Geolocators on legs give signals when passing Motus towers to track the birds - Nanotags a  re smaller tags that can be used to track insects as well Sub-Zero Temperatures - Plants Cold Hardiness - Extra water is withdrawn and evaporated from the leaves - Solute concentration is increased by water reduction and proactive sugar adding - Lowers plant freezing point - Cell membranes increase in flexibility, ice grows between them Acclimation - Phytochromes detect photoperiod change, causing cells to go dormant and the plant to become more responsive to lower temperatures - Cold temperatures cause ice to form in between the cells

Needle Retention

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Needle surface area is small, with closed stomata and thick cuticles for water retention Xanthophyll Pigment is used to protect internal integrity of the cells Chlorophyll uses the energy from the sun for heat

★ Skunk Cabbage has an unusual anticipation for the cold and heats itself up Desiccation - Drying of plants due to low humidity, worse on calm, sunny days - Underside of leaves is fuzzy in order to trap moisture and improve circulation - Deciduous trees drop leaves due to their high surface area, pigments change as the tree takes the nutrients from the leaves Ex: Red Maples turn red when male and yellow when female Extreme Heat - Plants -

Too much heat causes desiccation Surface area of leaves is reduced by leaf curling Water is retained by the closing of the stomata

Extreme Heat - Animals Behavioural Adaptations - Become less active and seek out cooler, shaded sites to rest - Surface area facing the sun is reduced Ex: D  ragonflies assume the Obelisk position, Tiger Beetles use stilting - Some animals use behavioural cooling techniques Ex: H  oneybees use their wings to fan the colony in the hive - Some animals use evaporative cooling by panting or sweating Turkey Vultures excrete on their legs Physiological Adaptations - Heat is shunted to body parts with greater surface area, Rete Mirabile is bypassed to encourage heat loss - Some animals use hyperthermia to lose heat to the environment  Ex: Mourning Doves raise their body temperature to 45ºC + NUTRITION Herbivory - When an animal eats plants

Predation

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When an animal eats other animals

Detrivore - Animal that eats dead plant material Filter Feeders - Animals which use the current of water in order to have food delivered to them Ex: Blackfly Larvae use their Labral Brushes to filter feed, Swans use Lamellae Northern Shovelers a  nd Puddle Ducks use their tongues to filter their food Plant Feeding -

Adaptations are required to feed from plants

Proboscis - A flexible and tubular mouthpart that elongates to suck juices Ex: B  utterflies Hyoid Apparatus - Muscles which help to further extend a tongue Ex: H  ummingbirds Stylets - Mouthparts which pierce and suck Ex: M  osquitos, Aphids Mandibles - Appendages near the mouth which crush and cut an insect’s food Ex: L  eaf Blotch Miners, which eat leaves from the inside Cheek Teeth - Large teeth with many grooves in the back of an animal’s mouth for crushing food Ex: Moose have these along with Masseter muscles Radula - Rasplike structure of small teeth Ex: S  nails Gizzard - Part of the digestive tract which serves to grind up food into small bits Ex: R  uffed Grouse

★ Caterpillars don’t have digestive enzymes, so their droppings are full of nutrients and  they are constantly eating Rumination - Processing food twice by swallowing, regurgitating cud and chewing it up further Ex: M  oose use rumination as well as having bacteria in their stomachs - Bacteria and moose have a S  ymbiotic relationship Coprophagy - When an animal eats their own droppings in order to gain missed nutrients Ex: Hares...