Flashcards in Exam 2 Deck (90):
What is a diploblast? a triploblast?
Dipoblast two germ layers (endoderm and mesoderm)
- Triploblast three germ layers (endoderm, mesoderm, ectoderm)
Ex. 2 layers cnidarian
Ex. 3 layers acoelomate platyhelminth
Ex. 3 layers coelomate echinoderm, mollusk, chordate
What is a coelom? What are the advantages to having a coelom?
coelom: fluid filled cavities between the gut and the body wall, found in most animals (within mesoderm)
-advantages shock absorber, container for circulating oxygen and nutrients, space for internal organs
-hydrostatic skeleton allows for movement
What is a protostome? A deuterostome? Give an example of an animal phylum that belongs to each group.
protostome is the first mouth (blastopore becomes mouth)
-formation of mouth before anus
-formation of coelom by splitting of a block of mesoderm
-ex. Arthropods, mollusks, annelids
- deuterostomes bilaterian animals (protostomes are also
bilaterians, and echinoderms sort of aren’t)
-formation of anus earlier than mouth
-formation of coelom by pinching off layers of mesoderm from the gut
-ex. Echinoderms and chordates
What is the function of ribosomes? Why is rRNA often used to assess phylogenetic relatedness among animal phyla?
large macromolecular machine that synthesizes proteins by
Using genetic information encoded in mRNA
-consists of 2 subunits, consisting of rRNA and proteins
-rRNA used to find relationships between phyla
-all animals possess rRNA because it is essential
-changes changes very slowly, can look at organisms that
Diverged long ago
-500+ million years
-more specialized DNA & RNA less useful for broad comparisons
In Fig. 33.2 (Phylogeny of Major Animal Phyla): Be able to explain why animals are monophyletic. Which phyla are deuterostomes? Which phyla have bilateral symmetry? Which phyla are triploblasts? Diploblasts? Which phyla have coeloms? What animal phylum is most closely related to Echinodermata? Most distantly related to Echinodermata? (We do not expect you to know this information without this phylogenetic tree as a reference)
- animals are monophyletic because the group “animals”
includes all descendants of a common ancestor
-sponges are paraphyletic and distantly related to other
-sponges are paraphyletic because they include two group from the common ancestor of all animals, but not all animals
Name and describe the hypotheses that may explain the Cambrian explosion.
-major rise in sea level
-evolutionary arms race facilitated by higher levels of
Ca++ (used to build shell)
-increased oxygen (higher metabolism, larger size, shell)
-duplication of hox genes
What are the names of the two phyla discussed and what are some examples of each? (e.g. poriferans are sponges)
-Cnidaria: jellyfish, corals, sea anemones
What is the level of organization of sponges?
-cellular level of organization, all life processes occur in cells
-no true tissues or organs
-cells carry out all functions
What are the two sponge cell types that we discussed in lecture and what are their functions?
-choanocytes: collar cells, pumps water (100’s L/day)
-capture food particles
-amoebocyte: use pseudopodia (like amoeba) to move through gelatinous substance of sponge
-digesting, transporting, storing food
-totipotent: can differentiate into any type of sponge cells
-important in growth and healing
5. What happens after you put a sponge in a blender and strain the cells to dissociate them? Why is this possible?
-cells can come back together & form full sponge
-mix 2 species in blender separate into 2 different sponges
-cell recognition & self organization
-kill outside cells
6. Be able to name the two adult body forms of cnidarians and describe the differences between the two.
-Polyp: cylinder w/ tentacles, mouth facing up attached to substrate, reproduce asexually
-Medusa: disk with tentacles mouth faces down, free swimming, reproduce sexually
7. Be able to describe the life cycle of a hydrozoan (e.g. slide 20) in general terms (e.g. Which body form reproduces asexually? Which reproduces sexually?).
- Medusa reproduce sexually and have separate sexes
- Polyp reproduce asexually
8. What type of symmetry do cnidarians possess? What is their level of organization?
- radial symmetry
- one opening: incomplete gut
- tissue level of organization (possess nervous and muscle tissue)
9. What is a cnidocyte? How does it work? What is a nematocyst?
-cnidocyte: stinger cells
-nematocyst: rapidly triggered by touch
-all cnidarias are predators
What are the three classes of Cnidaria that we discussed in lecture? (There is one other class which we didn’t discuss) Be able to give an example of each. Which of the two body forms of cnidarians are present and dominant in each of the classes?
-Hydrozoa: water animal (Portuguese man-of-war, Hydra) polyp main form (but also have medusa)
-Scyphozoa: true jellies medusa main form (but also have polyps)
-Anthozoa: corals and sea anemones polyp only (no medusa)
11. What is the genus name of the dinoflagellate symbiont of corals? What type of relationship does it have with coral? Justify your answer.
Symbiodium, mutualism – coral receives sugars, dinoflagellates receive shelter
What is coral bleaching? What causes it to occur?
-coral bleaching occurs when increased temperature (mostly), increased light, or pollution causes corals to lose their Symbiodinium symbionts (dinoflagellates)
-when coral loses its color and becomes white
What are the advantages of being as flat as a flatworm (Platyhelminthes)?
-high surface are to volume ratio
-need no specialized circulatory or respiratory system
-bilateral- have cephalization (heads)
-tripoblastic but acoelomate
-free living or parasitic
[not advantages of flat, but are flatworm features]
What worm causes Schistosomiasis and how do you catch it? What are the 2 hosts of Schistosoma? To which class does Schistosoma belong?
- Trematoda: the flukes
- Get it from water marine or fresh
- All trematodes have 2 hosts
o Produce asexually in snails
o Reproduce sexually in humans
[these hosts are specific to Schistosoma, although most trematodes do have mollusk and vertebrate hosts]
15. What is the cause of the large belly of people with Schistosomiasis?
caused by scar tissue from trapped eggs in intestines, bladder, and liver
16. What are the names of the 3 major classes of Platyhelminthes? Be able to give common names or an example of each. Which of the classes contain only parasites?
-Tubellaria: Dugesia, planarians (most predators, some parasitic)
-Trematoda: flukes, Schitosoma (all parasitic)
-Cestoda: tapeworms (all parasitic)
Why would a parasite want to take over its host behavior or change its appearance?
to move host
Where do adult tapeworms live? What structure do they use to stay attached?
-live in the guts of vertebrates
-attach w/ scolex (hooks & suckers)
What are four characteristics of the body plan of a mollusk. What is the function of each?
-radula: tiny teeth for feeding
-shell: protects body
-Mantle: secretes shell
-foot: muscular for movement
20. What are the names of the 3 major classes of Mollusca? Be able to give some examples of each.
-Gastropoda: snails, slugs, sea slugs
-Bivalvia: clams, oysters, mussels, scallops
-Cephalopoda: octopuses, squid, cuttlefish
What is the most endangered group of animals in North America? Why are they endangered?
- Freshwater mussels are the most endangered group of animal in NA. Endangered because of:
- Water pollution
- Impoundment (damming) of rivers changes habitat
- Invasive species (e.g. zebra mussel)
- FW mussel larvae are parasitic on specific fishes, which
are also endangered
What characteristic of octopus led to strong natural selection for high intelligence? What other defense mechanisms to octopus possess?
- lack of shell probably led to selection for intelligence
-most developed brain
-camouflage, beak, ink
23. On the slide about learning by Octopus vulgaris, be able to explain the graph. What does the graph indicate about how Octopus vulgaris learns?
they just have to see someone do it
-or they can be trained
24. What are the four main types of learning we discussed? Can you differentiate them?
-habituation: loss of responsiveness (used to)
-associative learning or classical conditioning: learning
What is segmentation? What are the benefits of possessing segmentation? What three phyla possess segmentation?
- Separated into different parts
- Conserve energy, makes injuries non-fatal
- Asexual reproduction
- High degree of specialization possible
- Allows for precise movement
26. What are chaetae? What is their function? Which group of annelids lacks them?
- Function is locomotion (for traction)
- Hirudinea lack chaetae (leeches)
What are the names of the 2 major classes of Annelida? Be able to provide examples of each.
Polychaeta: tube worms & clam worms
-Clitellata: oligochaete, leeches
How do Riftia worms survive without mouths and digestive tracts?
Which type of nutritional mode is used by the prokaryotes living in the Riftia?
-obtain nutrients from symbiotic bacteria
How do primary producers get their energy, carbon? What do primary and secondary consumers eat? What do primary decomposers eat?
-primary producers: plants and algae
-chemoautotrophs and photoautotrophs
-primary consumers: organisms that eat primary producers
-some animals, fungi, protists
-Decomposers: organsims that eat dead producers and other
Dead organisms (detritus)
-secondary consumers: carnivores eat primary consumers
What were medicinal leeches used for in the past? What are they used for today?
- In the past, leeches and bloodletting generally were used as treatments for literally everything: headache, cold, cancer, impotence, etc.
-secrete a protein which dissolves blood clots
-Today, still used re-attaching limbs and digits
1. What does the term Ecydysozoa mean? Why do Ecdysozoans need to molt? What two major phyla of animals we discussed are Ecydysozoans? Which Ecdysozoans are most abundant? Which are most diverse?
-have to molt to grow
-two major phyla: arthropods, and nematodes
-nematoda: most abundant animals
-arthropods: most diverse phyla
2. What makes a roundworm so round?
-coelom under high pressure (hydrostatic skeleton)
-cuticle: tough, waxy, and not flexible
3. Where do nematodes live?
-fresh water, marine, terrestrial, parasites of plants and animals in deep ground [basically everywhere]
4. What is the largest intracellular parasite? How do you catch it? Can you cure it?
- Trichinella is the largest intracellular parasite, meaning it lives inside host cells.
- In particular, juveniles live in muscle cells (adults live in intestines)
- Catch it from eating undercooked meat of omnivores (e.g. pigs, bears, cat, rat, etc.)
- Can’t be cured – so cook your pork and bear well!
5. Where do juveniles Trichinella worms live? How do they change the cell that they enter to ensure their long-term survival?
- Striated muscle of animals
- Each worm lives inside a single muscle cell, which they change into a nurse cell
- Becomes encapsulated
- Causes blood vessels to form around cell to get nutrients.
6. What are the four characteristics of the arthropod body plan?
-segmented into groups of functional parts (head, thorax, abdomen)
-cuticle: rigid exoskeleton
-open circulatory system
7. How does segmentation differ between the annelids and the arthropods?
- Annelids are segmented all over their body
- Arthropods are segmented into 3 parts
8. What is an open circulatory system?
- No blood vessels
- All open
9. What are the names of the 3 major subphyla of arthropods and what are some examples of each? You can easily distinguish among the subphyla with antennae and with their characteristic appendages. Be able to give the name and function of the characteristic appendage (e.g. chelicerae for Chelicerata) and the number of antennae present in each subphylum.
- Chelicerata- spiders, ticks and mice (Chelicerae)
-Insecta- ants, beetles, butterflies, mandible ( 1 pair of antennae)
-Crustacea- barnacles, crabs, isopods, water fleas, shrimp, lobster, mandible (2 pairs antennae)
10. For what trait are the Chelicerata named? What is the primary function of that trait?
-chelicerae: for feeding
-1st pair of appendages on head
-fangs on spider
11. Use the graph to explain one reason why female wolf spiders often eat their mates? Be able to read and interpret the graph.
-cannibalistic moms babies have a higher survival rate
12. What group of animals first invented flight?
13. What are some advantages of being able to fly?
-find different food/mates
-dispersal to new environments
14. What morphological trait do insects and crustaceans share? (hint, it is found on the head)
15. Why is molting so dangerous?
-many arthropods are unsuccessful at extracting themselves from exoskeleton
-movement is limited or impossible after molting (vulnerable)
-90% of arthropod mortality is associated with molting
1. List the two deuterostome phyla.
2. What is the water vascular system? What are the functions of the tube feet?
-water comes in a pore, tube feet are for locomotion and respiration
3. Besides the water vascular system and its associated structures, what are the other features of the body plan of an echinoderm?
-penta-radial symmetry (5 part)
4. What are the names of the 3 classes of echinoderms that we addressed and what are some examples of each?
-Asteroidea: sea stars
-Echinoidea: sea urchins
-Holothuroidea- sea cucumbers
5. Be able to define the term keystone species and to describe why Pisaster sea stars are a keystone species along the coast of the Pacific Northwest.
-important even when not abundant exceptionally great impact on other species even when not very abundant often because of what they eat
-eat mussels, which allows other animals to occur (without Pisaster, mussels take over)
6. What do sea urchins eat? How has their population explosion and their diet affected the kelp forests in the Pacific Ocean?
-eat kelp and can consume an entire kelp forest when there are too many to decrease biodiversity
7. What do sea cucumbers eat?
-eat dead things (detrivores)
8. What are the 4 defining traits of the phylum Chordata? What is the function of each trait?
-Dorsal, hollow nerve chord: bundle of nerve cells along the dorsal length of body (spinal chord and brain)
-pharyngeal gill slits: always for respiration and often feeding
-postanal tail: locomotion (tail bone)
-notochord: skeletal structures for supports in vertebras (vertebral column replaces function)
10. What is the common name for cephalochordates?
11. What are the common names of the urochordates?
-sea squirts, tunicates
12. What are the functions of the pharyngeal gill slits in urochordates and cephalochordates?
- Permit water taken into the mouth to be passed out of the body
- Filter feeding
- Used for respiration then into the lung
13. How does the morphology of larval and adult urochordates differ?
- Larvae have all four choradate traits
- Adults only have pharyngeal gill slits
1. Name and describe the two traits that define the subphylum Vertebrata.
- Elaborate head with cranium: large brain, image forming eyes, cranium protects brain
- Vertebral column: protects nerve chord, replaces function of notochord
2. What are the 5 main evolutionary innovations that occur in the subphylum Vertebrata? Why are each important to the evolution of vertebrates?
-vertebrae/cranium, jaws, bony skeleton, limbs, amniotic egg,
3. What vertebrates lack jaws? What vertebrates possess jaws? See Fig. 35.12?
-lampreys and hagfish lack jaws
-most vertebrates possess jaws (sharks, rays, skates, other fish, amphibians, reptiles, birds, mammals)
4. Describe the hypothesis for the evolutionary origin of vertebrate jaws that was discussed in class What are the benefits of possessing jaws?
-jaw likely evolved from two pairs of gill arches
-benefits: allows gripping, and animals to eat larger food
5. What are the skeletons of Chondrichthyes made of (hint what does the word Chondrichthyes mean)?
- Cartilage (chondr) fish (ichthyes)
6. What do the terms oviparous, viviparous, and ovoviviparous mean? Be able to explain how these reproductive modes differ and identify an example of each. What group of Chondrichthyes possesses all of these reproductive modes?
-oviparous: egg birth- hatched outside the mom
-viviparous: live birth- embryo develops inside mom and is nourished by a placenta
-ovovivparious: egg live birth- egg develops inside of mother, nourished by yolk (sharks)
7. Be able to explain why fish as a group are paraphyletic. Be able to explain why each individual lineage of fish is monophyletic. Refer to Fig. 35.12
- fish as a group are paraphyletic because they include some (e.g. chondricthyes, Actinopterygii) but not all (e.g. tetrapods are excluded) descendents of a common ancestor
- individual lineages (e.g. chondrichthyes) are monphyletic because the do include all descendants from a common evolutionary ancestor
8. Which vertebrates have bony skeletons?
-some fish (not chondricthyes), amphibians, mammals, and reptiles
9. What is the evolutionary origin of tetrapod limbs? Why possess limbs? Which vertebrates possess limbs?
-lobe like fin
-limb can support walking on land
-frogs, toads, salamander
10. What does Amphibia mean? To what does it refer? What are some major characteristics of amphibians?
-both sides of life [that is, both aquatic and terrestrial]
-they have 4 feet
- juveniles use gills, adults have lungs and respire across skin (cutaneous respiration)
11. How do amphibians breathe (both juveniles and adults)?
-juveniles: breath through gills
-adults: breathe through lungs and skin
Why are amphibians declining worldwide?
habitat destruction, pollution (pesticides), disease (chytrid fungi and others), drought
3. What are the major characteristics of mammals?
-posses mammary glands that produce milk
-fur or hair made of keratin
-endotherms: inside heat regulation
-most mammals are homeotherms
-4 chambered heart
4. Why can’t most adult mammals digest lactose?
mamma= mammary glands
-lactose: sugar, disaccharide of glucose and galactose
-very rare only found in milk
- most adult mammals are lactose intolerant
-milk is baby food
Where in the world are you most likely to find people who can digest lactose (milk)? Where in the world would you most likely to find people who cannot digest lactose? See the map in the lecture slides.
-people in North and Central Africa, N Eurasia, Australia, and America can digest milk
-retained lactose (enzyme) in adults
-South America, Southern Africa, and eastern Asia are lactose intolerant
Under what conditions did some human groups evolve the ability to digest (tolerate) lactose?
-historically people lived with ungulates (cow, sheep, goat) and drank and ate their products
What are the 3 major mammalian lineages? Be able to state how the 3 mammalian lineages differ by where their embryos develop. Be able to state examples of each lineage.
-Monotremes: mammary glands but no nipples
-lay eggs and hatch them
-duck billed platypus, ducks
-Marsupials: brief gestation, gives birth to underdeveloped offspring, most development is in marsupian (pouch)
-Eutherian: development with uterus and nourished by placenta
a. What are the three major benefits of retaining the embryo inside the body?
-protection from predators, drying out
-more developed when born
b. Which mammals are oviparous? Viviparous?
-viviparous: marsupials, and eutherian
8.Name and describe the characteristics of reptiles.
-amniotes (all posses amniotic eggs)
-dry skin covered in keratin (scales and feathers)
9. What traits to birds possess that are different from other reptiles?
-4 chambered heart
-feathers made of keratin
-endotherms, most are homeotherms
10. Define the following words: endotherm, ectotherm, homeotherm, and poikilotherm. Be able to identify examples in each combination (e.g. ectothermic poikilotherm).
-endotherm: heat regulation (inside)
-ectotherm: external sources for heat (sun)
-homeotherm: conastant heat
-Poikilotherm: very variable (cold cold, warm warm)
Endothermic homeotherm: most birds, mammals
Endothermic poikilotherm: humming bird
Ectothermic poikilotherm: reptiles (lizards, gators)
Ectothermic homeotherm: tapeworms, parasites
11. What are the only two groups of animals that are endotherms?
12. What is Gross Primary Productivity (GPP) and Net Primary Productivity (NPP)? Why are these concepts relevant to animals in ecosystems?
-GPP: amount of light energy per unit of biomass converted to chemical energy by primary producers
-NPP: gross- respiration
-it determines how much an animal is actually getting vs what is lost as respiration
13. What is Net Secondary Production? Why isn’t everything that an animal consumes used to make new biomass (in the form of growth or reproduction)?
-all the energy that is ingested, the portion that is used to make new biomass (growth and reproduction)
-rest of energy consumed leaves animal as feces or is lost as heat by cellular respiration
-once poop is gone energy is gone
14. What is production efficiency? Be able to compute production efficiencies if I give you the total energy consumed by animal, the total converted to net secondary production and the amounts lost to cellular respiration and feces.
= (net secondary production/ total Energy consumed)
15. Why are production efficiencies higher in ectotherms than in endotherms?
-temperature regulation causes inefficiency
-endotherms vs. ectotherms
Low production efficiency because so much energy is used to make heat in endotherms