Extra Bio

Question 1

Ethnology

Answer 1

• behavior from bio point of view - what genes code for behavior
• natural history of behavior
• biological mechanisms - unique look at behavior - tried dividing behaviors into measurable phases
• fathers of ethnology - Karl Von Frisch, Conrad Lorenz (imprinting - newborn birds would recognize him as their parent) and Niko Tinbergen (Noble Prize 1973)

Question 2

Goose Experiment

Answer 2

• pull out an egg and leave where mother sees it - mother will reach out with bill and scoot it back and sit back down
• Lorenz tried to break down behavior into component parts -
  
  • sign stimulus ex egg out of nest
  • innate releasing mechanism ex brain says need to get egg back in nest
  • fixed action potential ex physical behavior to scoot egg back
• particular stimulating input that initiates particular beahvrio and in brain theres a switch that says this behavior should be carried out
  
  • once behavior starts - its hard wired
• once goose has started this you can snatch egg out and put tennis ball back and goose keeps scooting it back
• genetic parts coding for specific things

Question 3

Behaviors effected by genes

Answer 3

• 2 species of lovebirds - each kind collect materials for nest in diff ways
  
  • peach-faced puts stick for nest under its wing
  • Fischer’s puts nest component in beak/bill
• made hybrid bird - pick up stick in beak, then stick under wings and then throw stick down

Question 4

Drosophila mating song

Answer 4

• males try to attact females by beating their wings in specific way
• period gene affects frequency of wing beats
  
  • we can alter period gene and cause wing beats to speed up or slow down or mutate it to inactive the gene
  • these tend to be less successful
  • by altering 1 specific gene you can change the behavior in their mating song

Question 5

Discriminate btwn Major Groups of Vertebrates

Answer 5

• Amphibians -thin, wet skin, doing respiration across their skin (gas exchange); primitive lungs w/few alveoli; lay their eggs in the water and have yolk sacs and chorion and allantois; restricted to wet areas; ectotherms
• Reptiles -thick scaly skin - no respiration, more lung surface area; do not need water for their eggs (cleidioc egg - self contained w/4 extraembryonic membranes - amnion (bag of water around dev embryo), yolk sac, chorion, allantois); can live in most places (not high or cold altitudes); ectotherms
• Birds - derive from reptiles, feathers - insulating material to keep us warm(wings), scales (legs), excellant lungs; derived from flying one and then got too big to fly or didn’t need to fly; endotherms so their body heat comes from inside; bird eggs are very similar to reptiles w/large yolk but tend to hang around egg and then care for the young
• Mammals - derive from reptiles; endotherms; w/activity 24/7 - originally were nocturnal so had to be active at night; lots of endurance; have fur (humans lost it to more efficiently cool themselves since in warm areas we evolved)
  
  • placental mammals - long gestation, shorter lactation
  • few mammals that lay eggs - monotremes (egg-laying mammals), echildna platypus;
  • marsupials don’t lay eggs but long period of lactation

Question 6

Populations

Answer 6

• distribution - distribution of animal population in space; often animals group together since envir where most happy or where their food exists; type of bat where entire pop in one cave - could wipe out entire species in one swoop
• population dispersion - starling invasion where released 120 of them in central park where they spread all over the place and billions
• increase of populations over time: dN/dt = r_iN
• N= # in population
• r_i = intrinsic rate of increase of species of organism
• will cont to increase at specified rate of increase since increasing by factor - gives exponential growth
• but then will be limited by something - resources in environment or space –> so usually see graph that exponential growth and then hits max rate (K = carrying capacity) and level off
  
  • as number gets close to K it will level off and stop
  • some species can be described as “R strategists” - small with rapid reproduction rates ex. bacteria
  • “K strategists” - larger, slower rates of replication, ex. deer or humans since can change carry capacity by increasing resources or building to increase space

Question 7

Population Growth

Answer 7

• could hit beyond 10 billion eventually
• increase K by building and expanding resources and space

Question 8

Predator-Prey Interactions

Answer 8

• showhoe hare and lynx
• hare cycles due to predation of the lynx - 1st hypothesis
• careful studies found - rabbits cycle int heir own population regardless of if lynx were there or not and see cycling of hares
• hare population crashes due to carry capacity sort of reason, and then lynx follows
• naturally occuring cycling of hares and then lynx follow that, is what is actually going on

Question 9

Batesian Mimicry

Answer 9

• Monarch vs. Viceroy butterfly
• monarch feeds on milkweed plant and tastes bitter when bird tries to eat it
  
  • protection
  • viceroy adapted to look like monarch to be left alone too - improves survival this way
    
    • fewer than monarchs so less than 50/50 chance of getting actual monarch

Question 10

Batesian Mimicry - wasp vs. hoverfly

Answer 10

• hoverfly has advantage of being scary and so left alone and keeps predators away
  
  • imitates appearance and size of wasp

Question 11

Dangerous Coloration

Answer 11

• yellow-black coloration
• known as Mullerian mimicry - adaptation for “dangerous coloration”
• so can have batesian mimicry but what you see is that in many types of organisms there are lots of them that get general black and yellow coloring

Question 12

Symbiotic relationship

Answer 12

• Symbiotic relationships – when two organisms live in an intimate association with each other.

Types:

1. Mutualism– When bothorganisms benefit from the symbiotic association.
   ex. thorns that get hallowed out by ants that live there - tree produces nutrient rich things on end of leaves for the ants which are dangerous and toxic so bite what ever tries to eat leaves of tree
2. Commensalism– When one organism benefits from the association while the second is unaffected.
   ex. mites in roots of hairs which provide nutrients for our skin cells
3. Parasitism– When one organism of the pairing benefits at the expense of the other. (Note: if this relationship shades over into a situation where the one organism is actively harming the other we called the harmful organism a pathogen(disease –causing)
   ex. parasite that causes problems

Question 13

Relationships can Co-evolve

Answer 13

• Co-evolution - when changes in at least two species’ genetic compositions reciprocally affect each other’s evolution
• both change - bat that feeds on necture of cactus that blooms only at night; face of bat fits right into the flower

Question 14

Bio-geocyling: Nitrogen Cycle

Answer 14

• Nitrogen used in organic compounds so need certain amount
• N in the atmosphere but in N2 where held together via triple bond
• nitrogen fixing bacteria - and then pass on nitrogen in environment to other types of organisms
  
  • ex. cyanobacteria
  • soil bacteria too
  • lightening
  • animals use nitrogen and then when die they get decomposed and broken down by additional bacteria and then can release it back in the atmosphere
• know: atmospheric nitrogen is pretty stable and only few types of bacteria that can fix it

Question 15

Rice paddies

Answer 15

• water fern in water in rice paddies which carries cyanobacterium - immeasurably better yield of rice

Question 16

Freshwater - rare commodity in world

Answer 16

• underground interconnected area within rocks and soil where freshwater is stored - can dig wells to irrigate their crops

Question 17

parasitic worms

Answer 17

• good at illustrating some evolutionary steps
• recall the 3 primary germ layers: that develop in animals - ectoderm, mesoderm, endoderm
  
  • deuterostomes vs protostome
  • coel (body cavity) is surrounded by all mesoderm in a true coelomate

Question 18

3 major types of worms

Answer 18

• flat worm - platyhelminthes; no coelom - cavity connects to external
• round worms - nematodes - weird body cavity - pseudocoelom (cavity betwn endoderm and mesoderm)
• segmented worms - annelids - true cavity/coelom (coelomates)
  
  • mesoderm layers come together and make a mesentary - many membranes that hold internal organs in place and provide pathway for blood vessels and nerves - true body cavity often have these

Question 19

Flat worm

Answer 19

• in fresh water, even caves
• don’t require much food
• eye spots are light sensitive cells (not really eyes)
• nerve cell bodies - ganglia
• flat worms are notorious because really good regenerators - cut in half and keep in nutrient conditions and makes 2 flat worms

Question 20

Round Worm

Answer 20

• pseudocoelom is seen
• mainly longitudinal muslces and not circumerential muscles so they kind of thrash and no circular muscles

Question 21

Segmented worms

Answer 21

• include earth worms
• and other worms that stick out of bay and feed
• includes leeches

Question 22

Parisitology

Answer 22

• all organisms have some parasite in them
• ex. tape worms have been found in ancient burials - humans and tape worms together for 100,000s years and so co-evolved together
• ex. deep sea fish where male hooks onto female and spends rest of life hooked there and gets all nutrition for female (male provides sperm when female needs it) - female sees a male, best to latch on and not let it go since might not see another one

Question 23

Parasitic wasps/bees

Answer 23

• capture catapillers(no brain - but wasp has to sting each section to keep it from moving away/paralyze)
  
  • wasp lays its eggs on the catipillar

Question 24

Parasitic Adaptations

Answer 24

• features we see in parasites in general:

1. Some form of attachment - hooks(tapeworm), suckers (sheep tapeworms has both)
   
   • in nutrient rich areas - food stream, lymph vessels, or GI tract - need to hold on or they are swept away
2. Resistance to digestion & immune system - mucous or resistance carbohydrates, or secrete a cuticle - thick outer layer made of fibrous proteins like collagen
3. System to penetrate the body - thru body via eating/drinking or swimming/boring
   
   • implies that parasite has multiple forms for entering and then living inside
   • may imply multiple hosts
4. Good at anaerobic metabolism - in blood stream lots of O2 but in gut no O2
5. Reduced digestive ability - some don’t digest at all because lots of broken down material for them to absorb directly broken down a.a. or sugars
6. Reduced sensory ability
7. Huge reproduction potential - isolated lifestyle and rarely encounter members of their species so when they do they send out lots and lots of eggs (often self fertilize)

Question 25

Most parasites we get

Answer 25

• from flat and round worms
• flat worms there are
  
  • trematoda - flukes
    
    • live in liver or blood
  • cestoda - tapeworms
    
    • tapeworms for all diff types of animals, pork, beef, etc.
• round worms - nematoda
  
  • bunch of types
  • round worm parasite for everything

Question 26

Life Cycles see parasitic features

Answer 26

• liver fluke in bile duct and sheds eggs in digestive tract that come out in waste and contaminate grasses
  
  • if eggs get washed into water then you can have marine snails that pick up the eggs and they hatch in the snail and create another form which metamorphisis into a swimming form called cercaria until drills into muscle of fish and if eat raw fish then they mature in your gut
  • several forms of host and type of parasite itself
• blood fluke - schistosomiasis
  
  • eggs in waste picked up by snail and people raise rice and swimming forms burrow into their skin and take up residence in the blood
  • male and female cicarian inside person via red spots on legs and they get together and stay together and mate inside human for rest of their lives and produce eggs
  • eggs re-contaminate the water
  • in some parts of water they have imported crayfish that like to eat snails that have parasite

Question 27

Tapeworms

Answer 27

• end w/scolex - hooks and suckers
• rest is strand of reproductive units - not segmented worm
  
  • live up to huge reproductive potential
• each unit has male and female parts so it can self fertilize and has segments each is called proglottids whcih can break off of intestinal tract and go out with waste so spreads eggs
• can grow super long but made to have parts break off and carry out the eggs
• eggs contaminate grass and pig eats contaminated grass and grow in pig’s muscle (eggs meant to hatch in egg and humans are infected via tapeworm in muscle and not eggs; if human gets contaminated greens in garden and eat eggs and egg encysted in the brain since used to hatching in the pig muscle) and if eat raw pork you can get this tapeworm

Question 28

Round worms - hook worms

Answer 28

• hooks in their teeth made of chitin so they can hold on; section where bit onto intestinal wall where holds on and produces anticlotting agents and take nutrients from blood vessles
• all unhook at same time with right meds and come pouring out

Question 29

intestinal round worms

Answer 29

make a mass of worm which creates intestinal blockages

Ascaris - intestinal round worm

Question 30

Trichinosis

Answer 30

causes diarrea

Question 31

Onchocerciasis - river blindness

Answer 31

• enter and cause blindness - cause by black fly that bites you and then infects retina since the worms attack CNS and eye and retina and optic nerve

Question 32

Fularial (roundworms) worms cause elephantiasis - swelling - since they live in lymph

Answer 32

tends to effect lower limbs or scrotum and cause elephantiasis - tons of swelling

Question 33

Guinea worm

Answer 33

gets into body and matures and then breaks out of body and into water and lays egg

if stay out of water you can break life cycle

matchstick worm - winds up on matchstick and get whole thing out slowly, very thin

• aside - hard to treat dogs with worms in the heart

Question 34

Leeches

Answer 34

• also parasitic - segmented worms
• sucker on both ends - one end is mouth where have sharp blades that leech has around jaws which uses to make cut in skin of victim
  
  • salivary has anticoagulants to blood flows smoothly and has numbing in the salivay glands too
  • leech feeds on earthworm
• leeches useful medically for blood sucking ability
  
  • remove blood from tissue for tissues that need to be reattached - small arteries can be reattached easily but reattaching veins is harder since smaller but they will reattach themselves within few days
  • blood flows into ear but can’t get out and so tissue could die and blood can clot so they take some leeches and excess blood is taken out by leeches and veins find each other and hook back up